Internet Engineering Task Force M. Fine Diffserv Working Group K. McCloghrie Internet-Draft Cisco Systems draft-ietf-diffserv-pib-06.txt J. Seligson Expires September 2002 K. Chan Nortel Networks S. Hahn C. Bell Intel A. Smith Allegro Networks F. Reichmeyer PFN March 2002 Differentiated Services Quality of Service Policy Information Base Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of [RFC2026]. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This document is a product of the IETF's Differentiated Services Working Group. Comments should be addressed to WG's mailing list at diffserv@ietf.org. The charter for Diffserv may be found at http://www.ietf.org/html.charters/diffserv-charter.html. Copyright c The Internet Society (2001). All Rights Reserved. Distribution of this memo is unlimited. Abstract This document describes a Policy Information Base (PIB) for a device implementing the Differentiated Services Architecture. The Policy Rule Classes defined here provide policy control of resources implementing the Differentiated Services Architecture. These Policy [Page 1] DiffServ QoS Policy Information Base March 2002 Rule Classes can be used with other none Differentiated Services Policy Rule Classes (defined in other PIBs) to provide for a comprehensive policy controlled mapping of service requirement to device resource capability and usage. Conventions used in this document The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC-2119]. 1. Glossary PRC Provisioning Class. A type of policy data. PRI Provisioning Instance. An instance of a PRC. PIB Policy Information Base. The database of policy information. PDP Policy Decision Point. See [RAP-FRAMEWORK]. PEP Policy Enforcement Point. See [RAP-FRAMEWORK]. PRID Provisioning Instance Identifier. Uniquely identifies an instance of a PRC. 2. Introduction [SPPI] describes a structure for specifying policy information that can then be transmitted to a network device for the purpose of configuring policy at that device. The model underlying this structure is one of well-defined policy rule classes and instances of these classes residing in a virtual information store called the Policy Information Base (PIB). This document specifies a set of policy rule classes specifically for configuring QoS Policy for Differentiated Services [DSARCH]. One way to provision policy is by means of the COPS protocol [COPS] with the extensions for provisioning [COPS-PR]. This protocol supports multiple clients, each of which may provision policy for a specific policy domain such as QoS. The PRCs defined in this DiffServ QoS PIB are intended for use by the COPS-PR QoS client type. Furthermore, these PRCs are in addition to any other PIBs that may be defined for the QoS client type in the future, as well as the PRCs defined in the Framework PIB [FR-PIB]. 3. Relationship to the Diffserv Informal Management Model This PIB is designed according to the Differentiated Services Informal Management Model documented in [MODEL]. The model describes the way that ingress and egress interfaces of an 'n'-port router are modeled. It describes the configuration and management of a Diffserv interface in terms of a Traffic Conditioning Block (TCB) which contains, by definition, zero or more classifiers, meters, actions, [Page 2] DiffServ QoS Policy Information Base March 2002 algorithmic droppers, queues and schedulers. These elements are arranged according to the QoS policy being expressed, always in that order. Traffic may be classified; classified traffic may be metered; each stream of traffic identified by a combination of classifiers and meters may have some set of actions performed on it; it may have dropping algorithms applied and it may ultimately be stored into a queue before being scheduled out to its next destination, either onto a link or to another TCB. When the treatment for a given packet must have any of those elements repeated in a way that breaks the permitted sequence {classifier, meter, action, algorithmic dropper, queue, scheduler}, this must be modeled by cascading multiple TCBs. The PIB represents this cascade by following the "Next" attributes of the various elements. They indicate what the next step in Diffserv processing will be, whether it be a classifier, meter, action, algorithmic dropper, queue, scheduler or a decision to now forward a packet. The PIB models the individual elements that make up the TCBs. The higher level concept of a TCB is not required in the parameterization or in the linking together of the individual elements, hence it is not used in the PIB itself and only mentioned in the text for relating the PIB with the [MODEL]. The actual distinguishing of which TCB a specific element is a part of is not needed for the instrumentation of a device to support the functionalities of DiffServ, but it is useful for conceptual reasons. By not using the TCB concept, this PIB allows any grouping of elements to construct TCBs, using rules indicated by the [MODEL]. This will minimize changes to this PIB if rules in [MODEL] change. The notion of a Data Path is used in this PIB to indicate the DiffServ processing a packet may experience. This Data Path is distinguished based on the Role Combination and the Direction of the flow the packet is part of. A Data Path Table Entry indicates the first of possibly multiple elements that will apply DiffServ treatment to the packet. 3.1. PIB Overview This PIB is structured based on the need to configure the sequential DiffServ treatments being applied to a packet, and the parameterization of these treatments. These two aspects of the configuration are kept separate throughout the design of the PIB, and are fulfilled using separate tables and data definitions. In addition, the PIB includes tables describing the capabilities and limitations of the device using a general extensible framework. These tables are reported to the PDP and assist the PDP with the configuration of functional elements that can be realized by the device. This capabilities and limitations exchange allows a single or multiple devices to support many different variations of a [Page 3] DiffServ QoS Policy Information Base March 2002 functional datapath element. Allowing diverse methods of providing a general functional datapath element. In this PIB, the ingress and egress portions of a router are configured independently but in the same manner. The difference is distinguished by an attribute in a table describing the start of the data path. Each interface performs some or all of the following high-level functions: - Classify each packet according to some set of rules. - Determine whether the data stream the packet is part of is within or outside its metering parameters - Perform a set of resulting actions such as counting and marking of the traffic with a Differentiated Services Code Point (DSCP) as defined in[DSFIELD]. - Apply appropriate drop policy, either simple or complex algorithmic drop functionality. - Enqueue the traffic for output in the appropriate queue, whose scheduler may shape the traffic or simply forward it with some minimum rate or maximum latency. The PIB therefore contains the following elements: Data Path Table This describes the starting point of DiffServ data paths within a single DiffServ device. This table describes interface role combination and interface direction specific data paths. Classifier Tables A general extensible framework for specifying a group of filters. Meter Tables A general extensible framework and one example of a parameterization table - TBParam table, applicable for Simple Token Bucket Meter, Average Rate Meter, Single Rate Three Color Meter, Two Rate Three Color Meter, and Sliding Window Three Color Meter. Action Tables A general extensible framework and examples of parameterization tables for Mark actions. The "multiplexer" and "null" actions described in [MODEL] are accomplished implicitly by means of the Prid structures of the other elements. Algorithmic Dropper Tables A general extensible framework for describing the dropper functional datapath element. This includes the absolute dropper and other queue measurement dependent algorithmic droppers. [Page 4] DiffServ QoS Policy Information Base March 2002 Queue and Scheduler Tables A general extensible framework for parameterizing queuing and scheduler systems. Notice Shaper is considered as a type of scheduler and is included here. Capabilities Tables A general extensible framework for defining the capabilities and limitations of the elements listed above. The capability tables allow intelligent configuration of the elements by a PDP. 4. Structure of the PIB 4.1. General Conventions The PIB consists of classes that represent functional elements in the data path (e.g. classifiers, meters, actions), and classes that specify parameters that apply to a certain type of functional element (e.g. a Token Bucket meter or a Mark action). Parameters are typically specified in a separate PRC to enable the use of parameter classes by multiple policies. Functional element PRCs use the Prid TC (defined in [SPPI]) to indicate indirection. A Prid is an object identifier that is used to specify an instance of a PRC in another table. A Prid is used to point to parameter PRC that applies to a functional element, such as which filter should be used for a classifier element. A Prid is also used to specify an instance of a functional element PRC that describes what treatment should be applied next for a packet in the data path. Note that the use of Prids to specify parameter PRCs allows the same functional element PRC to be extended with a number of different types of parameter PRC's. In addition, using Prids to indicate the next functional datapath element allows the elements to be ordered in any way. 4.2. DiffServ Data Paths This part of the PIB provides instrumentation for connecting the DiffServ Functional Elements within a single DiffServ device. Please refer to the [MODEL] for discussions on the valid sequencing and grouping of DiffServ Functional Elements. Given some basic information, e.g. the interface capability, role combination and direction, the first DiffServ Functional Element is determined. Subsequent DiffServ Functional Elements are provided by the "Next" pointer attribute of each entry of data path tables. A description of how this "Next" pointer is used in each table is provided in their respective DESCRIPTION clauses. 4.2.1. Data Path PRC The Data Path PRC provides the DiffServ treatment starting points for all packets of this DiffServ device. Each instance of this PRC [Page 5] DiffServ QoS Policy Information Base March 2002 specifies the interface capability, role combination and direction for the packet flow. There should be at most two entries for each (interface type, role combination) pair, one for ingress and one for egress. Each instance provides the first DiffServ Functional Element each packet at a specific interface (identified by the roles assigned to the interface) traveling in a specific relative direction should experience. Notice this table is interface specific, with the use of interface type and RoleCombination. To indicate explicitly that there are no Diffserv treatments for a particular interface type, role combination and direction, an instance of the Data Path PRC can be created with zeroDotZero in the qosDataPathStart attribute. This situation can also be indicated implicitly by not supplying an instance of a Data Path PRC for that particular interface type, role combination and direction. The explicit/implicit selection is up to the implementation. This means that the PEP should perform normal IP device processing when zeroDotZero is used in the qosDataPathStart attribute, or when the entry does not exist. Normal IP device processing will depend on the device; for example, this can be forwarding the packet. Based on implementation experience of network devices where data path functional elements are implemented in separate physical processors or application specific integrated circuits, separated by switch fabric, it seems that more complex notions of data path are required within the network device to correlate the different physically separate data path functional elements. For example, ingress processing may have determined a specific ingress flow that gets aggregated with other ingress flows at an egress data path functional element. Some of the information determined at the ingress data path functional element may need to be used by the egress data path functional element. In numerous implementations, such information has been carried by adding it to the frame/memory block used to carry the flow within the network device; some implementers have called such information a "preamble" or a "frame descriptor". Different implementations use different formats for such information. Initially one may think such information is implementation details within the network device that does not need to be exposed outside of the network device. But from Policy Control point of view, such information will be very useful in determining network resource usage feedback from the network device to the policy server. This is accomplished by using the Internal Label Marker and Filter PRCs defined in [FR-PIB]. 4.3. Classifiers The classifier and classifier element tables determine how traffic is sorted out. They identify separable classes of traffic, by reference to appropriate filters, which may select anything from an individual micro-flow to aggregates identified by DSCP. The classification is used to send these separate streams to appropriate Meter, Action, Algorithmic Dropper, Queue and Scheduler elements. For example, to indicate a multi-stage meter, sub-classes [Page 6] DiffServ QoS Policy Information Base March 2002 of traffic may be sent to different meter stages: e.g. in an implementation of the Assured Forwarding (AF) PHB [AF-PHB], AF11 traffic might be sent to the first meter, AF12 traffic might be sent to the second and AF13 traffic sent to the second meter stage's out- of-profile action. The concept of a classifier is the same as described in [MODEL]. The structure of the classifier and classifier element tables, is the same as the classifier described in [MODEL]. Classifier elements have an associated precedence order solely for the purpose of resolving ambiguity between overlapping filters. Filter with higher values of precedence are compared first; the order of tests for entries of the same precedence is unimportant. A datapath may consist of more than one classifier. There may be overlap of filter specification between filters of different classifiers. The first classifier functional datapath element encountered, as determined by the sequencing of diffserv functional datapath elements, will be used first. An important form of classifier is "everything else": the final stage of the classifier i.e. the one with the lowest precedence, must be "complete" since the result of an incomplete classifier is not necessarily deterministic - see [MODEL] section 4.1.2. When a classifier PRC is instantiated at the PEP, it should always have at least one classifier element table entry, the "everything else" classifier element, with its filter matching all IP packets. This "everything else" classifier element should be created by the PDP as part of the classifier setup. The PDP have full control of all classifier PRIs instantiated at the PEP. The definition of the actual filter to be used by the classifier is referenced via a Prid: this enables the use of any sort of filter table that one might wish to design, standard or proprietary. No filters are defined in this PIB. However, standard filters for IP packets are defined in the Framework PIB [FR-PIB]. 4.3.1. Classifier PRC Classifiers, used in various ingress and egress interfaces, are organized by the instances of the Classifier PRC. A data path entry points to a classifier entry. A classifier entry identifies a list of classifier elements. A classifier element effectively includes the filter entry, and points to a "next" classifier entry or other data path functional element. 4.3.2. Classifier Element PRC Classifier elements point to the filters which identify various classes of traffic. The separation between the "classifier element" and the "filter" allows us to use many different kinds of filters [Page 7] DiffServ QoS Policy Information Base March 2002 with the same essential semantics of "an identified set of traffic". The traffic matching the filter corresponding to a classifier element is given to the "next" data path functional element identified in the classifier element. An example of a filter that may be pointed to by a Classifier Element PRI is the frwkIpFilter PRC, defined in [FR-PIB]. 4.4. Meters A meter, according to [MODEL] section 5, measures the rate at which packets making up a stream of traffic pass it, compares this rate to some set of thresholds and produces some number (two or more) of potential results. A given packet is said to "conform" to the meter if, at the time that the packet is being looked at, the stream appears to be within the meter's profile. PIB syntax makes it easiest to define this as a sequence of one or more cascaded pass/fail tests, modeled here as if-then-else constructs. It is important to understand that this way of modeling does not imply anything about the implementation being "sequential": multi- rate/multi-profile meters e.g. those designed to support [SRTCM], [TRTCM], or [TSWTCM] can still be modeled this way even if they, of necessity, share information between the stages: the stages are introduced merely as a notational convenience in order to simplify the PIB structure. 4.4.1. Meter PRC The generic meter PRC is used as a base for all more specific forms of meter. The definition of parameters specific to the type of meter used is referenced via a pointer to an instance of a PRC containing those specifics. This enables the use of any sort of specific meter table that one might wish to design, standard or proprietary. One specific meter table is defined in this PIB module. Other meter tables may be defined in other PIB modules. 4.4.2. Token-Bucket Parameter PRC This is included as an example of a common type of meter. Entries in this table are referenced from the qosMeterSpecific attributes of meter PRC instances. The parameters are represented by a rate qosTBParamRate, a burst size qosTBParamBurstSize, and an interval qosTBparamInterval. The type of meter being parameterized is indicated by the qosTBParamType attribute. This is used to determine how the rate, burst and rate interval parameters are used. Additional meter parameterization classes can be defined in other PIBs when necessary. 4.5. Actions [Page 8] DiffServ QoS Policy Information Base March 2002 Actions include "no action", "mark the traffic with a DSCP" or "specific action". Other tasks such as "shape the traffic" or "drop based on some algorithm" are handled in other functional datapath elements rather than in actions. The "multiplexer", "replicator" and "null" actions described in [MODEL] are accomplished implicitly through various combinations of the other elements. This PIB uses the Action PRC qosActionTable to organize one Action's relationship with the element(s) before and after it. It allows Actions to be cascaded to enable multiple Actions be applied to a single traffic stream by using each entry's qosActionNext attribute. The qosActionNext attribute of the last action entry in the chain points to the next element in the TCB, if any, e.g. a Queueing element. It may also point at a next TCB. The parameters needed for the Action element will depend on the type of Action to be taken. Hence the PIB allows for specific Action Tables for the different Action types. This flexibility allows additional Actions be specified in other PIBs and also allows for the use of proprietary Actions without impact on those defined here. One may consider packet dropping as an Action element. Packet dropping is handled by the Algorithm Dropper datapath functional element. 4.5.1. DSCP Mark Action PRC This Action is applied to traffic in order to mark it with a Diffserv Codepoint (DSCP) value, specified in the qosDscpMarkActTable. 4.6. Queueing Elements These include Algorithmic Droppers, Queues and Schedulers, which are all inter-related in their use of queueing techniques. 4.6.1. Algorithmic Dropper PRC Algorithmic Droppers are represented in this PIB by instances of the Algorithmic Dropper PRC. An Algorithmic Dropper is assumed to operate indiscriminately on all packets that are presented at its input, all traffic separation should be done by classifiers and meters preceding it. Algorithmic Dropper includes many types of droppers, from the simple always dropper to the more complex random dropper. This is indicated by the qosAlgDropType attribute. Algorithmic Droppers have a close relationship with queuing, each [Page 9] DiffServ QoS Policy Information Base March 2002 Algorithmic Dropper Table entry contains a qosAlgDropQMeasure attribute, indicating which queue's state affects the calculation of the Algorithmic Dropper. Each entry also contains a qosAlgDropNext attribute which indicates to which queue the Algorithmic Dropper sinks its traffic. Algorithmic Droppers may also contain a pointer to specific detail of the drop algorithm, qosAlgDropSpecific. This PIB defines the detail for three drop algorithms: Tail Drop, Head Drop and Random Drop; other algorithms are outside the scope of this PIB module but the general framework is intended to allow for their inclusion via other PIB modules. One generally-applicable parameter of a dropper is the specification of a queue-depth threshold at which some drop action is to start. This is represented in this PIB, as a base attribute, qosAlgDropQThreshold, of the Algorithmic Dropper entry. The attribute, qosAlgDropQMeasure, specifies which queue's depth qosAlgDropQThreshold is to compare against. o An Always Dropper drops every packet presented to it. This type of dropper does not require any other parameter. o A Tail Dropper requires the specification of a maximum queue depth threshold: when the queue pointed at by qosAlgDropQMeasure reaches that depth threshold, qosAlgDropQThresh, any new traffic arriving at the dropper is discarded. This algorithm uses only parameters that are part of the qosAlgDropEntry. o A Head Dropper requires the specification of a maximum queue depth threshold: when the queue pointed at by qosAlgDropQMeasure reaches that depth threshold, qosAlgDropQThresh, traffic currently at the head of the queue is discarded. This algorithm uses only parameters that are part of the qosAlgDropEntry. o Random Droppers are recommended as a way to control congestion, in [QUEUEMGMT] and called for in the [AF-PHB]. Various implementations exist, which agree on marking or dropping just enough traffic to communicate with TCP-like protocols about congestion avoidance, but differ markedly on their specific parameters. This PIB attempts to offer a minimal set of controls for any random dropper, but expects that vendors will augment the PRC with additional controls and status in accordance with their implementation. This algorithm requires additional parameters on top of those in qosAlgDropEntry; these are discussed below. 4.6.2. Random Dropper PRC One example of a random dropper is a RED-like dropper. An example of the representation chosen in this PIB for this element is shown in Figure 1. [Page 10] DiffServ QoS Policy Information Base March 2002 Random droppers often have their drop probability function described as a plot of drop probability (P) against averaged queue length (Q). (Qmin, Pmin) then defines the start of the characteristic plot. Normally Pmin=0, meaning with average queue length below Qmin, there will be no drops. (Qmax, Pmax) defines a "knee" on the plot, after which point the drop probability become more progressive (greater slope). (Qclip, 1) defines the queue length at which all packets will be dropped. Notice this is different from Tail Drop because this uses an averaged queue length. Although it is possible for Qclip = Qmax. In the PIB module, qosRandomDropMinThreshBytes and qosRandomDropMinThreshPkts represent Qmin. qosRandomDropMaxThreshBytes and qosRandomDropMaxThreshPkts represent Qmax. qosAlgDropQThreshold represents Qclip. qosRandomDropProbMax represents Pmax. This PIB does not represent Pmin (assumed to be zero unless otherwise represented). In addition, since message memory is finite, queues generally have some upper bound above which they are incapable of storing additional traffic. Normally this number is equal to Qclip, specified by qosAlgDropQThreshold. Each random dropper specification is associated with a queue. This allows multiple drop processes (of same or different types) to be associated with the same queue, as different PHB implementations may require. This also allows for sequences of multiple droppers if necessary. AlgDrop Queue +-----------------+ +-------+ --->| Next --------- -- + +---------------->| Next -+--> | QMeasure -------+--+ | ... | | QThreshold | RandomDrop +-------+ | Type=randomDrop | +----------------+ | Specific -------+-->| MinThreshBytes | +-----------------+ | MaxThreshBytes | | ProbMax | | InvWeight | | SamplingRate | +----------------+ Figure 1: Example Use of the RandomDropTable for Random Droppers The calculation of a smoothed queue length may also have an important bearing on the behavior of the dropper: parameters may include the sampling interval or rate, and the weight of each sample. The performance may be very sensitive to the values of these parameters and a wide range of possible values may be required due to a wide range of link speeds. Most algorithms include a sample [Page 11] DiffServ QoS Policy Information Base March 2002 weight, represented here by qosRandomDropWeight. The availability of qosRandomDropSamplingRate as readable is important, the information provided by Sampling Rate is essential to the configuration of qosRandomDropWeight. Having Sampling Rate be configurable is also helpful, as line speed increases, the ability to have queue sampling be less frequent than packet arrival is needed. Note however that there is ongoing research on this topic, see e.g. [ACTQMGMT] and [AQMROUTER]. Additional parameters may be added in an enterprise PIB module, e.g. by using AUGMENTS on this table, to handle aspects of random drop algorithms that are not standardized here. NOTE: Deterministic Droppers can be viewed as a special case of Random Droppers with the drop probability restricted to 0 and 1. Hence Deterministic Droppers might be described by a Random Dropper with Pmin = 0, Pmax = 1, Qmin = Qmax = Qclip, the averaged queue length at which dropping occurs. 4.6.3. Queues and Schedulers The Queue PRC models simple FIFO queues, as described in [MODEL] section 7.1.1. The Scheduler PRC allows flexibility in constructing both simple and somewhat more complex queueing hierarchies from those queues. Of course, since TCBs can be cascaded multiple times on an interface, even more complex hierarchies can be constructed that way also. Queue PRC instances are pointed at by the "next" attributes of the upstream elements e.g. qosMeterSucceedNext. Note that multiple upstream elements may direct their traffic to the same Queue PRI. For example, the Assured Forwarding PHB suggests that all traffic marked AF11, AF12 or AF13 be placed in the same queue, after metering, without reordering. This would be represented by having the qosMeterSucceedNext of each upstream meter point at the same Queue PRI. NOTE: Queue and Scheduler PRIs are for data path description, they both use Scheduler Parameterization Table entries for diffserv treatment parameterization. A Queue Table entry specifies the scheduler it wants service from by use of its Next pointer. Each Scheduler Table entry represents the algorithm in use for servicing the one or more queues that feed it. The [MODEL] section 7.1.2 describes a scheduler with multiple inputs: this is represented in the PIB by having the scheduling parameters be associated with each input. In this way, sets of Queues can be grouped together as inputs to the same Scheduler. This table serves to represent the example scheduler described in the [MODEL]: other more complex representations might be created outside of this PIB. [Page 12] DiffServ QoS Policy Information Base March 2002 Both the Queue PRC and the Scheduler PRC use instances of the Scheduler Parameterization PRC to specify diffserv treatment parameterization. Scheduler Parameter PRC instances are used to parameterize each input that feeds into a scheduler. The inputs can be a mixture of Queue PRI's and Scheduler PRI's. Scheduler Parameter PRI's can be used/reused by one or more Queue and/or Scheduler Table entries. For representing a Strict Priority scheduler, each scheduler input is assigned a priority with respect to all the other inputs feeding the same scheduler, with default values for the other parameters. A higher-priority input which contains traffic that is not being delayed for shaping will be serviced before a lower-priority input. For Weighted Scheduling methods e.g. WFQ, WRR, the "weight" of a given scheduler input is represented with a Minimum Service Rate leaky-bucket profile which provides guaranteed minimum bandwidth to that input, if required. This is represented by a rate qosMinRateAbsolute; the classical weight is the ratio between that rate and the interface speed, or perhaps the ratio between that rate and the sum of the configured rates for classes. The rate may, alternatively, be represented by a relative value, as a fraction of the interface's current line rate, qosMinRateRelative to assist in cases where line rates are variable or where a higher-level policy might be expressed in terms of fractions of network resources. The two rate parameters are inter-related and changes in one may be reflected in the other. For weighted scheduling methods, one can say loosely, that WRR focuses on meeting bandwidth sharing, without concern for relative delay amongst the queues; where WFQ control both queue service order and amount of traffic serviced, providing meeting bandwidth sharing and relative delay ordering amongst the queues. A queue or scheduled set of queues (which is an input to a scheduler) may also be capable of acting as a non-work-conserving [MODEL] traffic shaper: this is done by defining a Maximum Service Rate leaky-bucket profile in order to limit the scheduler bandwidth available to that input. This is represented by a rate qosMaxRateAbsolute; the classical weight is the ratio between that rate and the interface speed, or perhaps the ratio between that rate and the sum of the configured rates for classes. The rate may, alternatively, be represented by a relative value, as a fraction of the interface's current line rate, qosMaxRateRelative. There was discussion in the working group about alternative modeling approaches, such as defining a shaping action or a shaping element. We did not take this approach because shaping is in fact something a scheduler does to its inputs, (which we model as a queue with a maximum rate or a scheduler whose output has a maximum rate) and we felt it was simpler and more elegant to simply describe it in that context. Other types of priority and weighted scheduling methods can be defined using existing parameters in qosMinRateEntry. NOTE: [Page 13] DiffServ QoS Policy Information Base March 2002 qosSchedulerMethod uses OBJECT IDENTIFIER syntax, with the different types of scheduling methods defined as OBJECT-IDENTITY. Future scheduling methods may be defined in other PIBs. This requires an OBJECT-IDENTITY definition, a description of how the existing objects are reused, if they are, and any new objects they require. NOTE: hierarchical schedulers can be parameterized using this PIB by having Scheduler Table entries feeds into Scheduler Table entry. 4.7. Specifying Device Capabilities The Diffserv PIB uses the Base PRC classes frwkPrcSupportTable and frwkCompLimitsTable defined in [FR-PIB] to specify what PRC's are supported by a PEP and to specify any limitations on that support. The PIB also uses the capability PRC's frwkIfCapSetTable and frwkIfRoleComboTable defined in [FR-PIB] to specify the device's interface types and role combinations. Each instance of the capability PRC frwkIfCapSetTable contains an OID that points to an instance of a PRC that describes some capability of that interface type. The Diffserv PIB defines several of these capability PRCs, which assist the PDP with the configuration of Diffserv functional elements that can be implemented by the device. Each of these capability PRCs contains a direction attribute that specifies the direction for which the capability applies. This attribute is defined in a base capability PRC, which is extended by each specific capability PRC. Classification capabilities, which specify the information elements the device can use to classify traffic, are reported using the qosIfClassificationCaps PRC. Metering capabilities, which indicate what the device can do with out-of-profile packets, are specified using the qosIfMeteringCaps PRC. Scheduling capabilities, such as the number of inputs supported, are reported using the qosIfSchedulingCaps PRC. Algorithmic drop capabilities, such as the types of algorithms supported, are reported using the qosIfAlgDropCaps PRC. Queue capabilities, such as the maximum number of queues, are reported using the qosIfQueueCaps PRC. Maximum Rate capabilities, such as the maximum number of max rate Levels, are reported using the qosIfMaxRateCaps PRC. Two PRC's are defined to allow specification of the element linkage capabilities of the PEP. The qosIfElmDepthCaps PRC indicates the maximum number of functional datapath elements that can be linked consecutively in a datapath. The qosIfElmLinkCaps PRC indicates what functional datapath elements may follow a specific type of element in a datapath. The capability reporting classes in the DiffServ and Framework PIB are meant to allow the PEP to indicate some general guidelines about what the device can do. They are intended to be an aid to the PDP when it constructs policy for the PEP. These classes do not necessarily allow the PEP to indicate every possible configuration [Page 14] DiffServ QoS Policy Information Base March 2002 that it can or cannot support. If a PEP receives a policy that it cannot implement, it must notify the PDP with a failure report. 5. PIB Usage Example This section provides some examples on how the different table entries of this PIB may be used together for a Diffserv Device. The usage of each individual attribute is defined within the PIB module itself. For the figures, all the PIB table entry and attribute names are assumed to have "qos" as their first common initial part of the name, with the table entry name assumed to be their second common initial part of the name. "0.0" is being used to mean zeroDotZero. And for Scheduler Method "= X" means "using the OID of qoxSchedulerX". 5.1. Data Path Example Notice Each entry of the DataPath table is used for a specific interface type handling a flow in a specific direction for a specific functional role-combination. For our example, we just define one of such entry. +---------------------+ |DataPath | | IfName ="IfCap1" | | Roles = "A+B" | | IfDirection=Ingress | +---------+ | Start --------------+--->|Clfr | +---------------------+ | Id=Dept | +---------+ Figure 2: DataPath Usage Example In Figure 2, we are using IfCap1 to indicate interface type with capability set 1 handling ingress flow for functional roles of _A+B_. We are using classifier for departments to lead us into the Classifier Example below. 5.2. Classifier and Classifier Element Example We want to show how a multilevel classifier can be built using the classifier tables provided by this PIB. Notice we didn't go into details of the filters because they are not defined by this PIB. Continuing from the Data Path example from the previous section, let say we want to perform the following classification functionality to do flow separation based on department and application type: if (Dept1) then take Dept1-action { if (Appl1) then take Dept1-Appl1-action. [Page 15] DiffServ QoS Policy Information Base March 2002 if (Appl2) then take Dept1-Appl2-action. if (Appl3) then take Dept1-Appl3-action. } if (Dept2) then take Dept2-action { if (Appl1) then take Dept2-Appl1-action. if (Appl2) then take Dept2-Appl2-action. if (Appl3) then take Dept2-Appl3-action. } if (Dept3) then take Dept3-action { if (Appl1) then take Dept3-Appl1-action. if (Appl2) then take Dept3-Appl2-action. if (Appl3) then take Dept3-Appl3-action. } The above classification logic is translated into PIB table entries below, with two levels of classifications. First for department: +---------+ |Clfr | | Id=Dept | +---------+ +-------------+ +-----------+ |ClfrElement | +-->|Clfr | | Id=Dept1 | | | Id=D1Appl | | ClfrId=Dept | | +-----------+ | Preced=NA | | | Next -------+--+ +------------+ | Specific ---+----->|Filter Dept1| +-------------+ +------------+ +-------------+ +-----------+ |ClfrElement | +-->|Clfr | | Id=Dept2 | | | Id=D2Appl | | ClfrId=Dept | | +-----------+ | Preced=NA | | | Next -------+--+ +------------+ | Specific ---+----->|Filter Dept2| +-------------+ +------------+ +-------------+ +-----------+ |ClfrElement | +-->|Clfr | | Id=Dept3 | | | Id=D3Appl | | ClfrId=Dept | | +-----------+ | Preced=NA | | | Next -------+--+ +------------+ | Specific ---+----->|Filter Dept3| +-------------+ +------------+ [Page 16] DiffServ QoS Policy Information Base March 2002 Second for application: +-----------+ |Clfr | | Id=D1Appl | +-----------+ +---------------+ +--------------+ |ClfrElement | +----------------->|Meter | | Id=D1Appl1 | | | Id=D1A1Rate1 | | ClfrId=D1Appl | | | SucceedNext -+--->... | Preced=NA | | | FailNext ----+--->... | Next ---------+--+ +------------+ | Specific ----+--->... | Specific -----+---->|Filter Appl1| +--------------+ +---------------+ +------------+ +---------------+ +--------------+ |ClfrElement | +----------------->|Meter | | Id=D1Appl2 | | | Id=D1A2Rate1 | | ClfrId=D1Appl | | | SucceedNext -+--->... | Preced=NA | | | FailNext ----+--->... | Next ---------+--+ +------------+ | Specific ----+--->... | Specific -----+---->|Filter Appl2| +--------------+ +---------------+ +------------+ +---------------+ +--------------+ |ClfrElement | +----------------->|Meter | | Id=D1Appl3 | | | Id=D1A3Rate1 | | ClfrId=D1Appl | | | SucceedNext -+--->... | Preced=NA | | | FailNext ----+--->... | Next ---------+--+ +------------+ | Specific ----+--->... | Specific -----+---->|Filter Appl3| +--------------+ +---------------+ +------------+ Figure 3: Classifier Usage Example The application classifiers for department 2 and 3 will be very much like the application classifier for department 1 shown above. Notice in this example, Filters for Appl1, Appl2, and Appl3 are reusable across the application classifiers. This classifier and classifier element example assumes the next differentiated services functional datapath element is Meter and lead us into the Meter Example section. 5.3. Meter Example A single rate simple Meter may be easy to envision, hence we will do a Two Rate Three Color [TRTCM] example, using two Meter table entries and two TBParam table entries. [Page 17] DiffServ QoS Policy Information Base March 2002 +--------------+ +---------+ +--------------+ +----------+ |Meter | +->|Action | +->| Meter | +->|Action | | Id=D1A1Rate1 | | | Id=Green| | | Id=D1A1Rate2 | | | Id=Yellow| | SucceedNext -+ + + - ---------+ | | SucceedNext -+-+ +----------+ | FailNext ----+-----------------+ | FailNext ----+--+ +-------+ | Specific -+ | | Specific -+ | +->|Action | +-----------+--+ +-----------+--+ | Id=Red| | | +-------+ | +------------+ | +------------+ +->|TBMeter | +->|TBMeter | | Type=TRTCM | | Type=TRTCM | | Rate | | Rate | | BurstSize | | BurstSize | | Interval | | Interval | +------------+ +------------+ Figure 4: Meter Usage Example For [TRTCM], the first level TBMeter entry is used for Committed Information Rate and Committed Burst Size Token Bucket, and the second level TBMeter entry is used for Peak Information Rate and Peak Burst Size Token Bucket. The other meters needed for this example will depend on the service class each classified flow uses. But their construction will be similar to the example given here. The TBMeter table entries can be shared by multiple Meter table entries. In this example the differentiated services functional datapath element following Meter is Action, detailed in the following section. 5.4. Action Example Typically Mark Action will be used, we will continue using the _Action, Id=Green_ branch off the Meter example. Recall this is the D1A1Rate1 SucceedNext branch, meaning the flow belongs to Department 1 Application 1, within the committed rate and burst size limits for this flow. We would like to Mark this flow with a specific DSCP and also with a device internal label. +-----------+ +-----------+ +--->AlgDropAF11 |Action | +----------------->|Action | | | Next -----+--+ +------------+ | Next -----+--+ +-------------+ | Specific -+---->|DscpMarkAct | | Specific -+--->|ILabelMarker | +-----------+ | Dscp=AF11 | +-----------+ | ILabel=D1A1 | +------------+ +-------------+ Figure 5: Action Usage Example [Page 18] DiffServ QoS Policy Information Base March 2002 This example uses the frwkILabelMarker PRC defined in [FR-PIB], showing the device internal label being used to indicate the micro flow that feeds into the aggregated AF flow. This device internal label may be used for flow accounting purposes and/or other data path treatments. 5.5. Dropper Examples The Dropper examples below will continue from the Action example above for AF11 flow. We will provide three different dropper setups, from simple to complex. The examples below may include some queuing structures, they are here only to show the relationship of the droppers to queuing and are not complete. Queuing examples are provided in later sections. 5.5.1. Tail Dropper Example The Tail Dropper is one of the simplest. For this example we just want to drop part of the flow that exceeds the queue's buffering capacity, 2 Mbytes. +--------------------+ +------+ |AlgDrop | +->|Q AF1 | | Id=AF11 | | +------+ | Type=tailDrop | | | Next --------------+-+--+ | QMeasure ----------+-+ | QThreshold=2Mbytes | | Specific=0.0 | +--------------------+ Figure 6: Tail Dropper Usage Example 5.5.2. Single Queue Random Dropper Example Use of Random Dropper will introduce the usage of qosRandomDropEntry as in the example below. +-----------------+ +------+ |AlgDrop | +->|Q AF1 | | Id=AF11 | | +------+ | Type=randomDrop | | | Next -----------+-+--+ | QMeasure -------+-+ | QThreshold | +----------------+ | Specific -------+-->|RandomDrop | +-----------------+ | MinThreshBytes | | MinThreshPkts | | MaxThreshBytes | | MaxThreshPkts | | ProbMax | [Page 19] DiffServ QoS Policy Information Base March 2002 | Weight | | SamplingRate | +----------------+ Figure 7: Single Queue Random Dropper Usage Example Notice for Random Dropper, qosAlgDropQThreshold contains the maximum average queue length, Qclip, for the queue being measured as indicated by qosQMeasure, the rest of the Random Dropper parameters are specified by qosRandomDropEntry as referenced by qosSpecific. In this example, both qosNext and qosQMeasure references the same queue. This is the simple case but qosQMeasure may reference another queue for PEP implementation supporting this feature. 5.5.3. Multiple Queue Random Dropper Example When network device implementation requires measuring multiple queues for determining the behavior of a drop algorithm, the existing PRCs defined in this PIB will be sufficient for the simple case, as indicated by this example. +-------------+ +------+ |AlgDrop | +----------------+-------------------+->|Q_AF1 | | Id=AF11 | | | | +------+ | Type=mQDrop | | | | | Next -------+-+ +------------+ | +------------+ | | QMeasure ---+-->|MQAlgDrop | | +->|MQAlgDrop | | | QThreshold | | Id=AF11A | | | | Id=AF11B | | | Specific | | Type | | | | Type | | +-------------+ | Next ------+-+ | | Next ------+-+ | ExceedNext +---+ | ExceedNext | +------+ | QMeasure --+-+ | QMeasure --+-->|Q AF2 | | QThreshold | | | QThreshold | +------+ | Specific + | | | Specific + | +----------+-+ | +----------+-+ | | +---+ +------+ | +------+ | | +->|Q AF1 | | | +------+ | | | | +----------------+ | +----------------+ +->|RandomDrop | +->|RandomDrop | | MinThreshBytes | | MinThreshBytes | | MinThreshPkts | | MinThreshPkts | | MaxThreshBytes | | MaxThreshBytes | | MaxThreshPkts | | MaxThreshPkts | | ProbMax | | ProbMax | | Weight | | Weight | | SamplingRate | | SamplingRate | +----------------+ +----------------+ Figure 8: Multiple Queue Random Dropper Usage Example [Page 20] DiffServ QoS Policy Information Base March 2002 For this example, we have two queues, Q_AF1 and Q_AF2, sharing the same buffer resources. We want to make sure the common buffer resource is sufficient to service the AF11 traffic, and we want to measure the two queues for determining the drop algorithm for AF11 traffic feeding into _Q_AF1_. Notice mQDrop is used for qosAlgDropType of qosAlgDropEntry to indicate Multiple Queue Dropping Algorithm. The common shared buffer resource is indicated by the use of qosAlgDropEntry, with their attributes used as follows: - qosAlgDropType indicates the algorithm used, mQDrop. - qosAlgDropNext is used to indicate the next functional data path element to handle the flow when no drop occurs. - qosAlgDropQMeasure is used as the anchor for the list of qosMQAlgDropEntry, one for each queue being measured. - qosAlgDropQThreshold is used to indicate the size of the shared buffer pool. - qosAlgDropSpecific can be used to reference instance of additional PRC (not defined in this PIB) if more parameters are required to describe the common shared buffer resource. For this example, there are two subsequent qosMQAlgDropEntry, one for each queue being measured, with its attributes used as follows: - qosMQAlgDropType indicates the algorithm used, for this example, both qosMQAlgDropType uses randomDrop. - qosMQAlgDropQMeasure indicates the queue being measured. - qosMQAlgDropNext indicates the next functional data path element to handle the flow when no drop occurs. - qosMQAlgDropExceedNext is used to indicate the next queue's qosMQAlgDropEntry. With the use of zeroDotZero to indicate the last queue. - qosMQAlgDropQMeasure is used to indicate the queue being measured. For this example, _Q AF1_ and _Q_AF2_ are the two queues used. - qosAlgDropQThreshold is used as in single queue Random Dropper. - qosAlgDropSpecific is used to reference the PRID that describes the dropper parameters as in its normal usage. For this example both qosAlgDropSpecific reference qosRandomDropEntrys. Notice the anchoring qosAlgDropEntry and the two qosMQAlgDropEntrys all have their Next attribute pointing to Q_AF1. This indicates: - If the packet does not need to be checked with the individual queue's drop processing because of abundance of common shared buffer resources, then the packet is sent to Q_AF1. - If the packet is not dropped due to current Q_AF1 conditions, then it is sent to Q_AF1. - If the packet is not dropped due to current Q_AF2 conditions, then it is sent to Q_AF1. This example also uses two qosRandomDropEntry for the two queues it measures. Their attribute usage is the same as if for single queue random dropper. [Page 21] DiffServ QoS Policy Information Base March 2002 Other more complex result combinations can be achieved by specifying a new PRC and referencing this new PRC with qosAlgDropSpecific of the anchoring qosAlgDropEntry. More simple usage can also be achieved when a single set of drop parameters are used for all queues being measured. This again can be referenced by the anchoring qosAlgDropSpecific. These are not defined in this PIB. 5.6. Queue and Scheduler Example The queue and scheduler example will continue from the dropper example in previous section. Concentrating in the queue and scheduler Diffserv datapath functional elements. Notice a shaper is constructed using queue and scheduler with MaxRate parameters. [Page 22] DiffServ QoS Policy Information Base March 2002 +------------+ +-----------------+ ---->|Q | +->|Scheduler | | Id=EF | | | Id=Diffserv | | Next ------+------------------------+ | Next=0.0 | | MinRate ---+--+ | | Method=Priority | | MaxRate -+ | | +----------+ | | MinRate=0.0 | +----------+-+ +-->|MinRate | | | MaxRate=0.0 | | | Priority | | +-----------------+ +----------+ | Absolute | | | | Relative | | | +-----------+ +----------+ | +->|MaxRate | | | Level | | | Absolute | | | Relative | | | Threshold | | +-----------+ +-------------+ | +----------+ +------------+ | ---->|Q | +-->|Scheduler | | | Id=AF1 | | | Id=AF | | | Next ----+--------------------+ | Next ------+--+ | MinRate -+-+ | | Method=WRR | | MaxRate | | +----------+ | | MinRate -+ | +----------+ +->|MinRate | | | MaxRate | | | Priority | | +----------+-+ | Absolute | | | | Relative | | +----------+ +----------+ | | +----------+ | | +------------+ ---->|Q | | +->|MinRate | | Id=AF2 | | | Priority | | Next ----+--------------------+ | Absolute | | MinRate -+-+ | | Relative | | MaxRate | | +----------+ | +------------+ +----------+ +->|MinRate | | | Priority | | | Absolute | | | Relative | | +----------+ | +----------+ | ---->|Q | | | Id=AF3 | | | Next ----+--------------------+ | MinRate -+-+ | MaxRate | | +----------+ +----------+ +->|MinRate | | Priority | | Absolute | | Relative | +----------+ Figure 9: Queue and Scheduler Usage Example [Page 23] DiffServ QoS Policy Information Base March 2002 This example shows the queuing system for handling EF, AF1, AF2, and AF3 traffic. It is assumed AF11, AF12, and AF13 traffic feeds into Queue AF1. And likewise for AF2x and AF3x traffic. The AF1, AF2, and AF3 Queues are serviced by the AF Scheduler using a Weighed Round Robin method. The AF Scheduler will service each of the queues feeding into it based on the minimum rate parameters of each queue. The AF and EF traffic are serviced by the DiffServ Scheduler using a Strict Priority method. The DiffServ Scheduler will service each of its inputs based on their priority parameter. Notice there is an upper bound to the servicing of EF traffic by the DiffServ Scheduler. This is accomplished with the use of maximum rate parameters. DiffServ Scheduler uses both the maximum rate and priority parameters when servicing the EF Queue. The DiffServ Scheduler is the last Diffserv datapath functional element in this datapath. It uses zeroDotZero in its Next attribute. 6. Summary of the DiffServ PIB The DiffServ PIB consists of one module containing the base PRCs for setting DiffServ policy, queues, classifiers, meters, etc., and also contains capability PRC's that allow a PEP to specify its device characteristics to the PDP. This module contains two groups, which are summarized in this section. QoS Capabilities Group This group consists of PRCs to indicate to the PDP the types of interface supported on the PEP in terms of their QoS capabilities and PRCs that the PDP can install in order to configure these interfaces (queues, scheduling parameters, buffer sizes, etc.) to affect the desired policy. This group describes capabilities in terms of the types of interfaces and takes configuration in terms of interface types and role combinations [FR-PIB]; it does not deal with individual interfaces on the device. QoS Policy Group This group contains configuration of the functional elements that comprise the QoS policy that applies to an interface and the specific parameters that describe those elements. This group contains classifiers, meters, actions, droppers, queues and schedulers. This group also contains the PRC that associates the datapath elements with role combinations. [Page 24] DiffServ QoS Policy Information Base March 2002 7. PIB Operational Overview This section provides an operation overview of configuring DiffServ QoS policy. After initial PEP to PDP communication setup, using [COPS-PR] for example, the PEP will provide to the PDP the PIB Provisioning Classes (PRCs), interface types, and interface type capabilities it supports. The PRCs supported by the PEP are reported to the PDP in the PRC Support Table, frwkPrcSupportTable defined in the framework PIB [FR- PIB]. Each instance of the frwkPrcSupportTable indicates a PRC that the PEP understands and for which the PDP can send class instances as part of the policy information. The interface types the PEP supports are described by rows in the interface type table, frwkIfCapsSetTable. Each row, or instance of this class contains a pointer to an instance of a PRC that describes the capabilities of the interface type. The capability objects may reside in the qosIfClassifierCapsTable, the qosIfMeterCapsTable, the qosIfSchedulerCapsTable, the qosIfElmDepthCapsTable, the qosIfElmOutputCapsTable, or in a table defined in another PIB. The PDP, with knowledge of the PEP's capabilities, then provides the PEP with administration domain and interface-specific policy information. Instances of the qosDataPathTable are used to specify the first element in the set of functional elements applied to an interface. Each instance of the qosDataPathTable applies to an interface type defined by its roles and direction (ingress or egress). [Page 25] DiffServ QoS Policy Information Base March 2002 8. PIB Definitions 8.1. The DiffServ Base PIB DIFFSERV-PIB PIB-DEFINITIONS ::= BEGIN IMPORTS Unsigned32, Integer32, MODULE-IDENTITY, MODULE-COMPLIANCE, OBJECT-TYPE, OBJECT-GROUP, pib, TEXTUAL-CONVENTION FROM COPS-PR-SPPI InstanceId, ReferenceId, Prid, TagId, TagReferenceId FROM COPS-PR-SPPI-TC zeroDotZero FROM SNMPv2-SMI TruthValue FROM SNMPv2-TC RoleCombination, PrcIdentifier, AttrIdentifier FROM FRAMEWORK-TC-PIB Dscp FROM DIFFSERV-DSCP-TC IfDirection FROM DIFFSERV-MIB BurstSize FROM INTEGRATED-SERVICES-MIB; qosPolicyPib MODULE-IDENTITY SUBJECT-CATEGORIES { tbd } -- DiffServ QoS COPS Client Type -- to be assigned by IANA LAST-UPDATED "200202281800Z" ORGANIZATION "IETF DIFFSERV WG" CONTACT-INFO " Michael Fine Cisco Systems, Inc. 170 West Tasman Drive San Jose, CA 95134-1706 USA Phone: +1 408 527 8218 Email: mfine@cisco.com Keith McCloghrie Cisco Systems, Inc. 170 West Tasman Drive, San Jose, CA 95134-1706 USA Phone: +1 408 526 5260 Email: kzm@cisco.com John Seligson Nortel Networks, Inc. 4401 Great America Parkway Santa Clara, CA 95054 USA Phone: +1 408 495 2992 Email: jseligso@nortelnetworks.com" DESCRIPTION [Page 26] DiffServ QoS Policy Information Base March 2002 "The PIB module containing a set of provisioning classes that describe quality of service (QoS) policies for DiffServ. It includes general classes that may be extended by other PIB specifications as well as a set of PIB classes related to IP processing." REVISION "200202281800Z" DESCRIPTION "Initial version, published as RFC xxxx." ::= { pib xxx } -- xxx to be assigned by IANA qosCapabilityClasses OBJECT IDENTIFIER ::= { qosPolicyPib 1 } qosPolicyClasses OBJECT IDENTIFIER ::= { qosPolicyPib 2 } qosPolicyParameters OBJECT IDENTIFIER ::= { qosPolicyPib 3 } qosPolicyPibConformance OBJECT IDENTIFIER ::= { qosPolicyPib 4 } -- -- Interface Capabilities Group -- -- -- Interface Type Capability Tables -- -- The Interface type capability tables define capabilities that may -- be associated with interfaces of a specific type. This PIB -- defines three such tables: a classification capabilities table, a -- metering capabilities table and a scheduling capabilities table. -- Other PIBs may define other capability tables to augment the -- capability definitions of these tables or to introduce completely -- new capabilities. -- -- The Base Capability Table -- qosBaseIfCapsTable OBJECT-TYPE SYNTAX SEQUENCE OF QosBaseIfCapsEntry PIB-ACCESS notify STATUS current DESCRIPTION "The Base Interface Capability class. This class represents a generic capability supported by a device in the ingress, egress or both directions." ::= { qosCapabilityClasses 1 } qosBaseIfCapsEntry OBJECT-TYPE SYNTAX QosBaseIfCapsEntry STATUS current DESCRIPTION "An instance of this class describes the qosBaseIfCaps class." PIB-INDEX { qosBaseIfCapsPrid } ::= { qosBaseIfCapsTable 1 } [Page 27] DiffServ QoS Policy Information Base March 2002 QosBaseIfCapsEntry ::= SEQUENCE { qosBaseIfCapsPrid InstanceId, qosBaseIfCapsDirection Integer32 } qosBaseIfCapsPrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosBaseIfCapsEntry 1 } qosBaseIfCapsDirection OBJECT-TYPE SYNTAX Integer32 { inbound(1), outbound(2), inAndOut(3) } STATUS current DESCRIPTION "This object specifies the direction(s) for which the capability applies. A value of 'inbound(1)' means the capability applies only to the ingress direction. A value of 'outbound(2)' means the capability applies only to the egress direction. A value of 'inAndOut(3)' means the capability applies to both directions." ::= { qosBaseIfCapsEntry 2 } -- -- The Classification Capability Table -- qosIfClassificationCapsTable OBJECT-TYPE SYNTAX SEQUENCE OF QosIfClassificationCapsEntry PIB-ACCESS notify STATUS current DESCRIPTION "This table specifies the classification capabilities of an interface type" ::= { qosCapabilityClasses 2 } qosIfClassificationCapsEntry OBJECT-TYPE SYNTAX QosIfClassificationCapsEntry STATUS current DESCRIPTION "An instance of this class describes the classification capabilities of an interface." [Page 28] DiffServ QoS Policy Information Base March 2002 EXTENDS { qosBaseIfCapsEntry } UNIQUENESS { qosBaseIfCapsDirection, qosIfClassificationCapsSpec } ::= { qosIfClassificationCapsTable 1 } QosIfClassificationCapsEntry ::= SEQUENCE { qosIfClassificationCapsSpec BITS } qosIfClassificationCapsSpec OBJECT-TYPE SYNTAX BITS { ipSrcAddrClassification(0), -- indicates the ability to classify based on -- IP source addresses ipDstAddrClassification(1), -- indicates the ability to classify based on -- IP destination addresses ipProtoClassification(2), -- indicates the ability to classify based on -- IP protocol numbers ipDscpClassification(3), -- indicates the ability to classify based on -- IP DSCP ipL4Classification(4), -- indicates the ability to classify based on -- IP layer 4 port numbers for UDP and TCP ipV6FlowID(5) -- indicates the ability to classify based on -- IPv6 FlowIDs. } STATUS current DESCRIPTION "Bit set of supported classification capabilities. In addition to these capabilities, other PIBs may define other capabilities that can then be specified in addition to the ones specified here (or instead of the ones specified here if none of these are specified)." ::= { qosIfClassificationCapsEntry 1 } -- -- Metering Capabilities -- qosIfMeteringCapsTable OBJECT-TYPE SYNTAX SEQUENCE OF QosIfMeteringCapsEntry PIB-ACCESS notify STATUS current DESCRIPTION "This table specifies the metering capabilities of an interface type" ::= { qosCapabilityClasses 3 } [Page 29] DiffServ QoS Policy Information Base March 2002 qosIfMeteringCapsEntry OBJECT-TYPE SYNTAX QosIfMeteringCapsEntry STATUS current DESCRIPTION "An instance of this class describes the classification capabilities of an interface." EXTENDS { qosBaseIfCapsEntry } UNIQUENESS { qosBaseIfCapsDirection, qosIfMeteringCapsSpec } ::= { qosIfMeteringCapsTable 1 } QosIfMeteringCapsEntry ::= SEQUENCE { qosIfMeteringCapsSpec BITS } qosIfMeteringCapsSpec OBJECT-TYPE SYNTAX BITS { SimpleTokenBucket(1), AvgRate(2), SrTCMBlind(3), SrTCMAware(4), TrTCMBlind(5), TrTCMAware(6), TswTCM(7) } STATUS current DESCRIPTION "Bit set of supported metering capabilities. As with classification capabilities, these metering capabilities may be augmented by capabilities specified in other PRCs (in other PIBs)." ::= { qosIfMeteringCapsEntry 1 } -- -- Algorithmic Dropper Capabilities -- -- This capability table indicates the types of algorithmic -- drop supported by an interface type for a specific flow -- direction. -- Additional capabilities affecting the drop functionalities -- are determined based on queue capabilities associated with -- specific instance of a dropper, hence not specified by -- this table. -- qosIfAlgDropCapsTable OBJECT-TYPE SYNTAX SEQUENCE OF QosIfAlgDropCapsEntry PIB-ACCESS notify [Page 30] DiffServ QoS Policy Information Base March 2002 STATUS current DESCRIPTION "This table specifies the algorithmic dropper capabilities of an interface type" ::= { qosCapabilityClasses 4 } qosIfAlgDropCapsEntry OBJECT-TYPE SYNTAX QosIfAlgDropCapsEntry STATUS current DESCRIPTION "An instance of this class describes the algorithm dropper capabilities of an interface." EXTENDS { qosBaseIfCapsEntry } UNIQUENESS { qosBaseIfCapsDirection, qosIfAlgDropCapsType, qosIfAlgDropCapsMQCount } ::= { qosIfAlgDropCapsTable 1 } QosIfAlgDropCapsEntry ::= SEQUENCE { qosIfAlgDropCapsType BITS, qosIfAlgDropCapsMQCount Unsigned32 } qosIfAlgDropCapsType OBJECT-TYPE SYNTAX BITS { tailDrop(2), headDrop(3), randomDrop(4), alwaysDrop(5), mQDrop(6) } STATUS current DESCRIPTION "The type of algorithm that droppers associated with queues may use. The tailDrop(2) algorithm means that packets are dropped from the tail of the queue when the associated queue's MaxQueueSize is exceeded. The headDrop(3) algorithm means that packets are dropped from the head of the queue when the associated queue's MaxQueueSize is exceeded. The randomDrop(4) algorithm means that an algorithm is executed which may randomly drop the packet, or drop other packet(s) from the queue in its place. The specifics of the algorithm may be proprietary. However, parameters would be specified in the qosRandomDropTable. The alwaysDrop(5) will drop every packet presented to it. The mQDrop(6) algorithm will drop packets based on measurement from multiple queues." ::= { qosIfAlgDropCapsEntry 1 } qosIfAlgDropCapsMQCount OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "Indicates the number of queues measured for the drop [Page 31] DiffServ QoS Policy Information Base March 2002 algorithm. This attribute is ignored when alwaysDrop(5) algorithm is used. This attribute contains the value of 1 for all drop algorithm types except for mQDrop(6), where this attribute is used to indicate the maximum number of qosMQAlgDropEntry that can be chained together." DEFVAL { 1 } ::= { qosIfAlgDropCapsEntry 2 } -- -- Queue Capabilities -- qosIfQueueCapsTable OBJECT-TYPE SYNTAX SEQUENCE OF QosIfQueueCapsEntry PIB-ACCESS notify STATUS current DESCRIPTION "This table specifies the scheduling capabilities of an interface type" ::= { qosCapabilityClasses 5 } qosIfQueueCapsEntry OBJECT-TYPE SYNTAX QosIfQueueCapsEntry STATUS current DESCRIPTION "An instance of this class describes the queue capabilities of an interface type." EXTENDS { qosBaseIfCapsEntry } UNIQUENESS { qosBaseIfCapsDirection, qosIfQueueCapsMinQueueSize, qosIfQueueCapsMaxQueueSize, qosIfQueueCapsTotalQueueSize } ::= { qosIfQueueCapsTable 1 } QosIfQueueCapsEntry ::= SEQUENCE { qosIfQueueCapsMinQueueSize Unsigned32, qosIfQueueCapsMaxQueueSize Unsigned32, qosIfQueueCapsTotalQueueSize Unsigned32 } qosIfQueueCapsMinQueueSize OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "Some interfaces may allow the size of a queue to be configured. This attribute specifies the minimum size that can be configured for a queue, specified in bytes." ::= { qosIfQueueCapsEntry 1 } qosIfQueueCapsMaxQueueSize OBJECT-TYPE SYNTAX Unsigned32 STATUS current [Page 32] DiffServ QoS Policy Information Base March 2002 DESCRIPTION "Some interfaces may allow the size of a queue to be configured. This attribute specifies the maximum size that can be configured for a queue, specified in bytes." ::= { qosIfQueueCapsEntry 2 } qosIfQueueCapsTotalQueueSize OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "Some interfaces may have a limited buffer space to be shared amongst all queues of that interface while also allowing the size of each queue to be configurable. To prevent the situation where the PDP configures the sizes of the queues in excess of the total buffer available to the interface, the PEP can report the total buffer space in bytes available with this capability." ::= { qosIfQueueCapsEntry 3 } -- -- Scheduler Capabilities -- qosIfSchedulerCapsTable OBJECT-TYPE SYNTAX SEQUENCE OF QosIfSchedulerCapsEntry PIB-ACCESS notify STATUS current DESCRIPTION "This table specifies the scheduler capabilities of an interface type" ::= { qosCapabilityClasses 6 } qosIfSchedulerCapsEntry OBJECT-TYPE SYNTAX QosIfSchedulerCapsEntry STATUS current DESCRIPTION "An instance of this class describes the scheduler capabilities of an interface type." EXTENDS { qosBaseIfCapsEntry } UNIQUENESS { qosBaseIfCapsDirection, qosIfSchedulerCapsServiceDisc, qosIfSchedulerCapsMaxInputs } ::= { qosIfSchedulerCapsTable 1 } QosIfSchedulerCapsEntry ::= SEQUENCE { qosIfSchedulerCapsServiceDisc OBJECT IDENTIFIER, qosIfSchedulerCapsMaxInputs Unsigned32, qosIfSchedulerCapsMinMaxRate BITS } qosIfSchedulerCapsServiceDisc OBJECT-TYPE SYNTAX OBJECT IDENTIFIER STATUS current [Page 33] DiffServ QoS Policy Information Base March 2002 DESCRIPTION "The scheduling discipline for which the set of capabilities specified in this object apply. Object identifiers for several general purpose and well-known scheduling disciplines are defined in the Scheduler Method Parameters section of this PIB. These include Priority, WRR, WFQ." ::= { qosIfSchedulerCapsEntry 1 } qosIfSchedulerCapsMaxInputs OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "The maximum number of queues and/or schedulers that can feed into a scheduler indicated by this capability entry for this interface type. A value of zero means there is no maximum." ::= { qosIfSchedulerCapsEntry 2 } qosIfSchedulerCapsMinMaxRate OBJECT-TYPE SYNTAX BITS { MinRate(0), MaxRate(1), MinAndMaxRates(2) } STATUS current DESCRIPTION "Scheduler capability indicating ability to handle inputs with minimum rate, maximum rate, or both." ::= { qosIfSchedulerCapsEntry 3 } -- -- Maximum Rate Capabilities -- qosIfMaxRateCapsTable OBJECT-TYPE SYNTAX SEQUENCE OF QosIfMaxRateCapsEntry PIB-ACCESS notify STATUS current DESCRIPTION "This table specifies the maximum rate capabilities of an interface type" ::= { qosCapabilityClasses 7 } qosIfMaxRateCapsEntry OBJECT-TYPE SYNTAX QosIfMaxRateCapsEntry STATUS current DESCRIPTION "An instance of this class describes the maximum rate capabilities of an interface type." EXTENDS { qosBaseIfCapsEntry } UNIQUENESS { qosBaseIfCapsDirection, qosIfMaxRateCapsMaxLevels } [Page 34] DiffServ QoS Policy Information Base March 2002 ::= { qosIfMaxRateCapsTable 1 } QosIfMaxRateCapsEntry ::= SEQUENCE { qosIfMaxRateCapsMaxLevels Unsigned32 } qosIfMaxRateCapsMaxLevels OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "The maximum number of levels a maximum rate specification may have for this interface type and flow direction." ::= { qosIfMaxRateCapsEntry 1 } -- -- Datapath Element Linkage Capabilities -- -- -- Datapath Element Cascade Depth -- qosIfElmDepthCapsTable OBJECT-TYPE SYNTAX SEQUENCE OF QosIfElmDepthCapsEntry PIB-ACCESS notify STATUS current DESCRIPTION "This table specifies the number of elements of the same type that can be cascaded together in a data path." ::= { qosCapabilityClasses 8 } qosIfElmDepthCapsEntry OBJECT-TYPE SYNTAX QosIfElmDepthCapsEntry STATUS current DESCRIPTION "An instance of this class describes the cascade depth for a particular functional datapath element PRC. A functional datapath element not represented in this table can be assumed to have no specific maximum depth." EXTENDS { qosBaseIfCapsEntry } UNIQUENESS { qosBaseIfCapsDirection, qosIfElmDepthCapsPrc } ::= { qosIfElmDepthCapsTable 1 } QosIfElmDepthCapsEntry ::= SEQUENCE { qosIfElmDepthCapsPrc PrcIdentifier, qosIfElmDepthCapsCascadeMax Unsigned32 } [Page 35] DiffServ QoS Policy Information Base March 2002 qosIfElmDepthCapsPrc OBJECT-TYPE SYNTAX PrcIdentifier STATUS current DESCRIPTION "The object identifier of a PRC that represents a functional datapath element. This may be one of: qosClfrElementEntry, qosMeterEntry, qosActionEntry, qosAlgDropEntry, qosQEntry, or qosSchedulerEntry. The value is the OID of the table entry. There may not be more than one instance of this class with the same value of qosIfElmDepthCapsPrc." ::= { qosIfElmDepthCapsEntry 1 } qosIfElmDepthCapsCascadeMax OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "The maximum number of elements of type qosIfElmDepthCapsPrc that can be linked consecutively in a data path. A value of zero indicates there is no specific maximum." ::= { qosIfElmDepthCapsEntry 2 } -- -- Datapath Element Linkage Types -- qosIfElmLinkCapsTable OBJECT-TYPE SYNTAX SEQUENCE OF QosIfElmLinkCapsEntry PIB-ACCESS notify STATUS current DESCRIPTION "This table specifies what types of datapath functional elements may be used as the next downstream element for a specific type of functional element." ::= { qosCapabilityClasses 9 } qosIfElmLinkCapsEntry OBJECT-TYPE SYNTAX QosIfElmLinkCapsEntry STATUS current DESCRIPTION "An instance of this class specifies a PRC that may be used as the next functional element after a specific type of element in a data path." EXTENDS { qosBaseIfCapsEntry } UNIQUENESS { qosBaseIfCapsDirection, qosIfElmLinkCapsPrc, qosIfElmLinkCapsAttr, qosIfElmLinkCapsNextPrc } ::= { qosIfElmLinkCapsTable 1 } QosIfElmLinkCapsEntry ::= SEQUENCE { [Page 36] DiffServ QoS Policy Information Base March 2002 qosIfElmLinkCapsPrc PrcIdentifier, qosIfElmLinkCapsAttr AttrIdentifier, qosIfElmLinkCapsNextPrc PrcIdentifier } qosIfElmLinkCapsPrc OBJECT-TYPE SYNTAX PrcIdentifier STATUS current DESCRIPTION "The value is the OID of a PRC that represents a functional datapath element. This OID must not have the value zeroDotZero." ::= { qosIfElmLinkCapsEntry 1 } qosIfElmLinkCapsAttr OBJECT-TYPE SYNTAX AttrIdentifier STATUS current DESCRIPTION "The value represents the attribute in the PRC indicated by qosIfElmLinkCapsPrc that is used to specify the next functional element in the datapath. The attribute value corresponds to the order in which the attribute appears in the definition of the PRC. A value of 1 indicates the first attribute of the PRC, a value of 2 indicates the second attribute of the PRC, and so forth." ::= { qosIfElmLinkCapsEntry 2 } qosIfElmLinkCapsNextPrc OBJECT-TYPE SYNTAX PrcIdentifier STATUS current DESCRIPTION "The value is the OID of a PRC table entry from which instances can be referenced by the attribute indicated by qosIfElmLinkCapsPrc and qosIfElmLinkAttr. For example, suppose a meter's success output can be an action or another meter, and the fail output can only be an action. This can be expressed as follows: Prid Prc Attr NextPrc 1 qosMeterEntry qosMeterSucceedNext qosActionEntry 2 qosMeterEntry qosMeterSucceedNext qosMeterEntry 3 qosMeterEntry qosMeterFailNext qosActionEntry. zeroDotZero is a valid value for this attribute to specify that the PRC specified in qosIfElmLinkCapsPrc is the last functional data path element." ::= { qosIfElmLinkCapsEntry 3 } [Page 37] DiffServ QoS Policy Information Base March 2002 -- -- Policy Classes -- -- -- Data Path Table -- -- The Data Path Table enumerates the Differentiated Services -- Functional Data Paths within this device. Each entry specifies -- the first functional datapath element to process data flow -- for each specific datapath. Each datapath is defined by the -- interface role combination and direction. This table can -- therefore have up to two entries for each role combination, -- ingress and egress. qosDataPathTable OBJECT-TYPE SYNTAX SEQUENCE OF QosDataPathEntry PIB-ACCESS install STATUS current DESCRIPTION "The data path table indicates the start of functional data paths in this device." ::= { qosPolicyClasses 1 } qosDataPathEntry OBJECT-TYPE SYNTAX QosDataPathEntry STATUS current DESCRIPTION "Each entry in this table indicates the start of a single functional data path, defined by its interface name, role combination and traffic direction. The first functional datapath element to handle traffic for each data path is defined by the qosDataPathStart attribute of each table entry. Notice for each entry: 1. qosDataPathIfName must reference an existing interface capability name in frwkIfCapSetTable [FR-PIB]. 2. qosDataPathRoles must reference existing Role Combination in frwkIfRoleComboTable [FR-PIB]. 3. qosDataPathStart must reference an existing entry in a functional data path element table. If any one or more of these three requirements is not satisfied, the qosDataPathEntry will not be installed." PIB-INDEX { qosDataPathPrid } UNIQUENESS { qosDataPathIfName, qosDataPathRoles, qosDataPathIfDirection } ::= { qosDataPathTable 1 } [Page 38] DiffServ QoS Policy Information Base March 2002 QosDataPathEntry ::= SEQUENCE { qosDataPathPrid InstanceId, qosDataPathIfName SnmpAdminString, qosDataPathRoles RoleCombination, qosDataPathIfDirection IfDirection, qosDataPathStart Prid } qosDataPathPrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosDataPathEntry 1 } qosDataPathIfName OBJECT-TYPE SYNTAX SnmpAdminString STATUS current DESCRIPTION "The interface capability set to which this data path entry applies. The interface capability name specified by this attribute must exist in the frwkIfCapSetTable [FR-PIB] prior to association with an instance of this class." ::= { qosDataPathEntry 2 } qosDataPathRoles OBJECT-TYPE SYNTAX RoleCombination STATUS current DESCRIPTION "The interfaces to which this data path entry applies, specified in terms of roles. There must exist an entry in the frwkIfRoleComboTable [FR-PIB] specifying this role combination, together with the interface capability set specified by qosDataPathIfName, prior to association with an instance of this class." ::= { qosDataPathEntry 3 } qosDataPathIfDirection OBJECT-TYPE SYNTAX IfDirection STATUS current DESCRIPTION "Specifies the direction for which this data path entry applies on this interface." ::= { qosDataPathEntry 4 } qosDataPathStart OBJECT-TYPE SYNTAX Prid [Page 39] DiffServ QoS Policy Information Base March 2002 STATUS current DESCRIPTION "This selects the first functional datapath element to handle traffic for this data path. This Prid should point to an instance of one of: qosClfrEntry qosMeterEntry qosActionEntry qosAlgDropEntry qosQEntry The PRI pointed to must exist prior to the installation of this datapath start element." ::= { qosDataPathEntry 5 } [Page 40] DiffServ QoS Policy Information Base March 2002 -- -- Classifiers -- -- Classifier allows multiple classifier elements, of same or -- different types, to be used together. -- A classifier must completely classify all packets presented to -- it. This means all traffic handled by a classifier must match -- at least one classifier element within the classifier, -- with the classifier element parameters specified by a filter. -- It is the PDP's responsibility to create a _catch all_ classifier -- element and filter that matches all packet. This _catch all_ -- classifier element should have the lowest Precedence value. -- If there is ambiguity between classifier elements of different -- classifier, classifier linkage order indicates their precedence; -- the first classifier in the link is applied to the traffic first. -- Each entry in the classifier table represents a classifier, with -- classifier element table handling the fan-out functionality of a -- classifier, and filter table defining the classification -- patterns. -- -- -- Classifier Table -- -- The Classifier Table enumerates the Diffserv classifiers in this -- device. Each classifier is referenced by its classifier elements -- using its classifier ID. -- qosClfrTable OBJECT-TYPE SYNTAX SEQUENCE OF QosClfrEntry PIB-ACCESS install STATUS current DESCRIPTION "This table enumerates all the Diffserv classifier functional data path elements of this device. The actual classification definitions are detailed in qosClfrElementTable entries belonging to each classifier. An entry in this table, referenced by an upstream functional data path element or a datapath table entry, is the entry point to the classifier functional data path element. The qosClfrId of each entry is used to organize all classifier elements belonging to the same classifier." REFERENCE "[MODEL] section 4.1" ::= { qosPolicyClasses 2 } [Page 41] DiffServ QoS Policy Information Base March 2002 qosClfrEntry OBJECT-TYPE SYNTAX QosClfrEntry STATUS current DESCRIPTION "An entry in the classifier table describes a single classifier. Each classifier element belonging to this classifier must have its qosClfrElementClfrId attribute equal to qosClfrId." PIB-INDEX { qosClfrPrid } UNIQUENESS { qosClfrId } ::= { qosClfrTable 1 } QosClfrEntry ::= SEQUENCE { qosClfrPrid InstanceId, qosClfrId TagReferenceId } qosClfrPrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosClfrEntry 1 } qosClfrId OBJECT-TYPE SYNTAX TagReferenceId PIB-TAG { qosClfrElementClfrId } STATUS current DESCRIPTION "Identifies a Classifier. A Classifier must be complete, this means all traffic handled by a Classifier must match at least one Classifier Element within the Classifier." ::= { qosClfrEntry 2 } -- -- Classifier Element Table -- -- Entries in the classifier element table serves as -- the anchor for each classification pattern, defined -- in filter table entries. Each classifier element -- table entry also specifies the subsequent downstream -- diffserv functional datapath element when the -- classification pattern is satisfied. -- Each entry in the classifier element table describes -- one branch of the fan-out characteristic of a classifier -- indicated in [MODEL] section 4.1. A classifier is made up -- of one or more classifier elements. [Page 42] DiffServ QoS Policy Information Base March 2002 -- -- If there is ambiguity between classifier elements of the same -- classifier, then qosClfrElementPrecedence needs to be used. -- qosClfrElementTable OBJECT-TYPE SYNTAX SEQUENCE OF QosClfrElementEntry PIB-ACCESS install STATUS current DESCRIPTION "The classifier element table enumerates the relationship between classification patterns and subsequent downstream diffserv functional data path elements. Classification parameters are defined by entries of filter tables pointed to by qosClfrElementSpecific. There can be filter tables of different types, and they can be inter-mixed and used within a classifier. An example of a filter table is the frwkIpFilterTable, defined in [FR-PIB], for IP Multi-Field Classifiers (MFCs)." REFERENCE "[MODEL] section 4.1" ::= { qosPolicyClasses 3 } qosClfrElementEntry OBJECT-TYPE SYNTAX QosClfrElementEntry STATUS current DESCRIPTION "An entry in the classifier element table describes a single element of the classifier." PIB-INDEX { qosClfrElementPrid } UNIQUENESS { qosClfrElementClfrId, qosClfrElementPrecedence, qosClfrElementSpecific } ::= { qosClfrElementTable 1 } QosClfrElementEntry ::= SEQUENCE { qosClfrElementPrid InstanceId, qosClfrElementClfrId TagId, qosClfrElementPrecedence Unsigned32, qosClfrElementNext Prid, qosClfrElementSpecific Prid } qosClfrElementPrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosClfrElementEntry 1 } [Page 43] DiffServ QoS Policy Information Base March 2002 qosClfrElementClfrId OBJECT-TYPE SYNTAX TagId STATUS current DESCRIPTION "A classifier is composed of one or more classifier elements. Each classifier element belonging to the same classifier uses the same classifier ID. Hence, A classifier Id identifies which classifier this classifier element is a part of. This needs to be the value of qosClfrId attribute for an existing instance of qosClfrEntry." ::= { qosClfrElementEntry 2 } qosClfrElementPrecedence OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "The relative order in which classifier elements are applied: higher numbers represent classifier elements with higher precedence. Classifier elements with the same precedence must be unambiguous i.e. they must define non-overlapping patterns, and are considered to be applied simultaneously to the traffic stream. Clas- sifier elements with different precedence may overlap in their filters: the classifier element with the highest precedence that matches is taken. On a given interface, there must be a complete clas- sifier in place at all times in the ingress direction. This means that there will always be one or more filters that match every possible pat- tern that could be presented in an incoming packet. There is no such requirement in the egress direction." DEFVAL { 0 } ::= { qosClfrElementEntry 3 } qosClfrElementNext OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "This attribute provides one branch of the fan-out functionality of a classifier described in [MODEL] section 4.1. This selects the next diffserv functional datapath element to handle traffic for this data path. A value of zeroDotZero marks the end of DiffServ processing for this data path. Any other value must point to a [Page 44] DiffServ QoS Policy Information Base March 2002 valid (pre-existing) instance of one of: qosClfrEntry qosMeterEntry qosActionEntry qosAlgDropEntry qosQEntry." DEFVAL { zeroDotZero } ::= { qosClfrElementEntry 4 } qosClfrElementSpecific OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "A pointer to a valid entry in another table that describes the applicable classification filter, e.g. an entry in frwkIpFilterTable [FR-PIB]. The PRI pointed to must exist prior to the installation of this classifier element. The value zeroDotZero is interpreted to match any- thing not matched by another classifier element - only one such entry may exist for each classifier." DEFVAL { zeroDotZero } ::= { qosClfrElementEntry 5 } [Page 45] DiffServ QoS Policy Information Base March 2002 -- -- Meters -- -- This PIB supports a variety of Meters. It includes a -- specific definition for Meters whose parameter set can -- be modelled using Token Bucket parameters. -- Other metering parameter sets can be defined by other PIBs. -- -- Multiple meter elements may be logically cascaded -- using their qosMeterSucceedNext and qosMeterFailNext pointers if -- required. -- One example of this might be for an AF PHB implementation -- that uses multiple level conformance meters. -- -- Cascading of individual meter elements in the PIB is intended -- to be functionally equivalent to multiple level conformance -- determination of a packet. The sequential nature of the -- representation is merely a notational convenience for this PIB. -- -- srTCM meters (RFC 2697) can be specified using two sets of -- qosMeterEntry and qosTBParamEntry. First set specifies the -- Committed Information Rate and Committed Burst Size -- token-bucket. Second set specifies the Excess Burst -- Size token-bucket. -- -- trTCM meters (RFC 2698) can be specified using two sets of -- qosMeterEntry and qosTBParamEntry. First set specifies the -- Committed Information Rate and Committed Burst Size -- token-bucket. Second set specifies the Peak Information -- Rate and Peak Burst Size token-bucket. -- -- tswTCM meters (RFC 2859) can be specified using two sets of -- qosMeterEntry and qosTBParamEntry. First set specifies the -- Committed Target Rate token-bucket. Second set specifies the -- Peak Target Rate token-bucket. qosTBParamInterval in each -- token bucket reflects the Average Interval. -- qosMeterTable OBJECT-TYPE SYNTAX SEQUENCE OF QosMeterEntry PIB-ACCESS install STATUS current DESCRIPTION "This table enumerates specific meters that a system may use to police a stream of traffic. The traffic stream to be metered is determined by the element(s) upstream of the meter i.e. by the object(s) that point to each entry in this table. This may include all traffic on an interface. Specific meter details are to be found in table entry referenced by qosMeterSpecific." [Page 46] DiffServ QoS Policy Information Base March 2002 REFERENCE "[MODEL] section 5.1" ::= { qosPolicyClasses 4 } qosMeterEntry OBJECT-TYPE SYNTAX QosMeterEntry STATUS current DESCRIPTION "An entry in the meter table describes a single conformance level of a meter." PIB-INDEX { qosMeterPrid } UNIQUENESS { qosMeterSucceedNext, qosMeterFailNext, qosMeterSpecific } ::= { qosMeterTable 1 } QosMeterEntry ::= SEQUENCE { qosMeterPrid InstanceId, qosMeterSucceedNext Prid, qosMeterFailNext Prid, qosMeterSpecific Prid } qosMeterPrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosMeterEntry 1 } qosMeterSucceedNext OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "If the traffic does conform, this selects the next diffserv functional datapath element to handle traffic for this data path. The value zeroDotZero in this variable indicates no further Diffserv treatment is performed on traffic of this datapath. Any other value must point to a valid (pre-existing) instance of one of: qosClfrEntry qosMeterEntry qosActionEntry qosAlgDropEntry qosQEntry." DEFVAL { zeroDotZero } ::= { qosMeterEntry 2 } [Page 47] DiffServ QoS Policy Information Base March 2002 qosMeterFailNext OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "If the traffic does not conform, this selects the next diffserv functional datapath element to handle traffic for this data path. The value zeroDotZero in this variable indicates no further Diffserv treatment is performed on traffic of this datapath. Any other value must point to a valid (pre-existing) instance of one of: qosClfrEntry qosMeterEntry qosActionEntry qosAlgDropEntry qosQEntry." DEFVAL { zeroDotZero } ::= { qosMeterEntry 3 } qosMeterSpecific OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "This indicates the behaviour of the meter by point- ing to an entry containing detailed parameters. Note that entries in that specific table must be managed explicitly. For example, qosMeterSpecific may point to an entry in qosTBMeterTable, which contains an instance of a single set of Token Bucket parameters. The PRI pointed to must exist prior to installing this Meter datapath element." ::= { qosMeterEntry 4 } -- -- Token-Bucket Parameter Table -- -- Each entry in the Token Bucket Parameter Table parameterizes -- a single token bucket. Multiple token buckets can be -- used together to parameterize multiple levels of -- conformance. -- -- Note that an entry in the Token Bucket Parameter Table can -- be shared, pointed to, by multiple qosMeterTable entries. -- qosTBParamTable OBJECT-TYPE [Page 48] DiffServ QoS Policy Information Base March 2002 SYNTAX SEQUENCE OF QosTBParamEntry PIB-ACCESS install STATUS current DESCRIPTION "This table enumerates token-bucket meter parameter sets that a system may use to police a stream of traffic. Such parameter sets are modelled here as each having a single rate and a single burst size. Multiple entries are used when multiple rates/burst sizes are needed." REFERENCE "[MODEL] section 5.1" ::= { qosPolicyClasses 5 } qosTBParamEntry OBJECT-TYPE SYNTAX QosTBParamEntry STATUS current DESCRIPTION "An entry that describes a single token-bucket parameter set." PIB-INDEX { qosTBParamPrid } UNIQUENESS { qosTBParamType, qosTBParamRate, qosTBParamBurstSize, qosTBParamInterval } ::= { qosTBParamTable 1 } QosTBParamEntry ::= SEQUENCE { qosTBParamPrid InstanceId, qosTBParamType OBJECT IDENTIFIER, qosTBParamRate Unsigned32, qosTBParamBurstSize BurstSize, qosTBParamInterval Unsigned32 } qosTBParamPrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosTBParamEntry 1 } qosTBParamType OBJECT-TYPE SYNTAX OBJECT IDENTIFIER STATUS current DESCRIPTION "The Metering algorithm associated with the Token-Bucket parameters. zeroDotZero indicates this is unknown. Standard values for generic algorithms are as follows: [Page 49] DiffServ QoS Policy Information Base March 2002 qosTBParamSimpleTokenBucket, qosTBParamAvgRate, qosTBParamSrTCMBlind, qosTBParamSrTCMAware, qosTBParamTrTCMBlind, qosTBParamTrTCMAware, qosTBParamTswTCM These are specified in this PIB as OBJECT-IDENTITYs under qosPolicyParameters; additional values may be further specified in other PIBs." REFERENCE "[MODEL] section 5" ::= { qosTBParamEntry 2 } qosTBParamRate OBJECT-TYPE SYNTAX Unsigned32 UNITS "kilobits per second" STATUS current DESCRIPTION "The token-bucket rate, in kilobits per second (kbps). This attribute is used for: 1. CIR in RFC 2697 for srTCM 2. CIR and PIR in RFC 2698 for trTCM 3. CTR and PTR in RFC 2859 for TSWTCM 4. AverageRate in [MODEL] section 5." ::= { qosTBParamEntry 3 } qosTBParamBurstSize OBJECT-TYPE SYNTAX BurstSize UNITS "Bytes" STATUS current DESCRIPTION "The maximum number of bytes in a single transmission burst. This attribute is used for: 1. CBS and EBS in RFC 2697 for srTCM 2. CBS and PBS in FRC 2698 for trTCM 3. Burst Size in [MODEL] section 5." ::= { qosTBParamEntry 4 } qosTBParamInterval OBJECT-TYPE SYNTAX Unsigned32 UNITS "microseconds" STATUS current DESCRIPTION "The time interval used with the token bucket. For: 1. Average Rate Meter, [MODEL] section 5.2.1, -Delta. 2. Simple Token Bucket Meter, [MODEL] section 5.1, - time interval t. 3. RFC 2859 TSWTCM, - AVG_INTERVAL. 4. RFC 2697 srTCM, RFC 2698 trTCM, - token bucket update time interval." [Page 50] DiffServ QoS Policy Information Base March 2002 ::= { qosTBParamEntry 5 } [Page 51] DiffServ QoS Policy Information Base March 2002 -- -- Actions -- -- -- The Action Table allows enumeration of the different -- types of actions to be applied to a traffic flow. -- qosActionTable OBJECT-TYPE SYNTAX SEQUENCE OF QosActionEntry PIB-ACCESS install STATUS current DESCRIPTION "The Action Table enumerates actions that can be per- formed to a stream of traffic. Multiple actions can be concatenated. For example, after marking a stream of traffic exiting from a meter, a device can then perform a mark action of the conforming or non- conforming traffic. Specific actions are indicated by qosAction- Specific which points to an entry of a specific action type parameterizing the action in detail." REFERENCE "[MODEL] section 6." ::= { qosPolicyClasses 6 } qosActionEntry OBJECT-TYPE SYNTAX QosActionEntry STATUS current DESCRIPTION "Each entry in the action table allows description of one specific action to be applied to traffic." PIB-INDEX { qosActionPrid } UNIQUENESS { qosActionNext, qosActionSpecific } ::= { qosActionTable 1 } QosActionEntry ::= SEQUENCE { qosActionPrid InstanceId, qosActionNext Prid, qosActionSpecific Prid } qosActionPrid OBJECT-TYPE SYNTAX InstanceId STATUS current [Page 52] DiffServ QoS Policy Information Base March 2002 DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosActionEntry 1 } qosActionNext OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "This selects the next diffserv functional datapath element to handle traffic for this data path. The value zeroDotZero in this variable indicates no further Diffserv treatment is performed on traffic of this datapath. Any other value must point to a valid (pre-existing) instance of one of: qosClfrEntry qosMeterEntry qosActionEntry qosAlgDropEntry qosQEntry." DEFVAL { zeroDotZero } ::= { qosActionEntry 2 } qosActionSpecific OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "A pointer to an object instance providing additional information for the type of action indicated by this action table entry. For the standard actions defined by this PIB module, this should point to an instance of qosDscpMarkActEntry. For other actions, it may point to an instance of a PRC defined in some other PIB. The PRI pointed to must exist prior to installing this action datapath entry." ::= { qosActionEntry 3 } -- DSCP Mark Action Table -- -- Rows of this table are pointed to by qosActionSpecific -- to provide detailed parameters specific to the DSCP -- Mark action. -- This table should at most contain one entry for each supported -- DSCP value. These entries should be reused by different -- qosActionEntry in same or different data paths. -- [Page 53] DiffServ QoS Policy Information Base March 2002 qosDscpMarkActTable OBJECT-TYPE SYNTAX SEQUENCE OF QosDscpMarkActEntry PIB-ACCESS install STATUS current DESCRIPTION "This table enumerates specific DSCPs used for marking or remarking the DSCP field of IP packets. The entries of this table may be referenced by a qosActionSpecific attribute." REFERENCE "[MODEL] section 6.1" ::= { qosPolicyClasses 7 } qosDscpMarkActEntry OBJECT-TYPE SYNTAX QosDscpMarkActEntry STATUS current DESCRIPTION "An entry in the DSCP mark action table that describes a single DSCP used for marking." PIB-INDEX { qosDscpMarkActPrid } UNIQUENESS { qosDscpMarkActDscp } ::= { qosDscpMarkActTable 1 } QosDscpMarkActEntry ::= SEQUENCE { qosDscpMarkActPrid InstanceId, qosDscpMarkActDscp Dscp } qosDscpMarkActPrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosDscpMarkActEntry 1 } qosDscpMarkActDscp OBJECT-TYPE SYNTAX Dscp STATUS current DESCRIPTION "The DSCP that this Action uses for marking/remarking traffic. Note that a DSCP value of -1 is not permit- ted in this table. It is quite possible that the only packets subject to this Action are already marked with this DSCP. Note also that Diffserv may result in packet remarking both on ingress to a net- work and on egress from it and it is quite possible that ingress and egress would occur in the same router." ::= { qosDscpMarkActEntry 2 } [Page 54] DiffServ QoS Policy Information Base March 2002 -- -- Algorithmic Drop Table -- -- Algorithmic Drop Table is the entry point for the Algorithmic -- Dropper functional data path element. -- For a simple algorithmic dropper, a single algorithmic drop entry -- will be sufficient to parameterize the dropper. -- For more complex algorithmic dropper, the qosAlgDropSpecific -- attribute can be used to reference an entry in a parameter table, -- e.g. qosRandomDropTable for random dropper. -- For yet more complex dropper, for example, dropper that measures -- multiple queues, each queue with its own algorithm, can use a -- qosAlgDropTable entry as the entry point for Algorithm Dropper -- functional data path element, leaving the dropper parameters -- for each queue be specified by entries of qosMQAlgDropTable. -- In such usage, the anchoring qosAlgDropEntry's qosAlgDropType -- should be mQDrop, and its qosAlgDropQMeasure should reference -- the subsequent qosMQAlgDropEntry's, its qosAlgDropSpecific -- should be used to reference parameters applicable to all the -- queues being measured. -- The subsequent qosMQAlgDropEntry's will provide the parameters, -- one for each queue being measured. The qosMQAlgDropEntry's are -- chained using their qosMQAlgDropNext attributes. -- qosAlgDropTable OBJECT-TYPE SYNTAX SEQUENCE OF QosAlgDropEntry PIB-ACCESS install STATUS current DESCRIPTION "The algorithmic drop table contains entries describ- ing a functional data path element that drops packets according to some algorithm." REFERENCE "[MODEL] section 7.1.3" ::= { qosPolicyClasses 9 } qosAlgDropEntry OBJECT-TYPE SYNTAX QosAlgDropEntry STATUS current DESCRIPTION "An entry describes a process that drops packets according to some algorithm. Further details of the algorithm type are to be found in qosAlgDropType and with more detail parameter entry pointed to by qosAlgDropSpecific when necessary." [Page 55] DiffServ QoS Policy Information Base March 2002 PIB-INDEX { qosAlgDropPrid } UNIQUENESS { qosAlgDropType, qosAlgDropNext, qosAlgDropQMeasure, qosAlgDropQThreshold, qosAlgDropSpecific } ::= { qosAlgDropTable 1 } QosAlgDropEntry ::= SEQUENCE { qosAlgDropPrid InstanceId, qosAlgDropType INTEGER, qosAlgDropNext Prid, qosAlgDropQMeasure Prid, qosAlgDropQThreshold Unsigned32, qosAlgDropSpecific Prid } qosAlgDropPrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosAlgDropEntry 1 } qosAlgDropType OBJECT-TYPE SYNTAX INTEGER { other(1), tailDrop(2), headDrop(3), randomDrop(4), alwaysDrop(5), mQDrop(6) } STATUS current DESCRIPTION "The type of algorithm used by this dropper. A value of tailDrop(2), headDrop(3), or alwaysDrop(5) represents an algorithm that is completely specified by this PIB. A value of other(1) indicates that the specifics of the drop algorithm are specified in some other PIB module, and that the qosAlgDropSpecific attribute points to an instance of a PRC in that PIB that specifies the information necessary to implement the algorithm. The tailDrop(2) algorithm is described as follows: qosAlgDropQThreshold represents the depth of the queue, pointed to by qosAlgDropQMeasure, at which all newly arriving packets will be dropped. [Page 56] DiffServ QoS Policy Information Base March 2002 The headDrop(3) algorithm is described as follows: if a packet arrives when the current depth of the queue, pointed to by qosAlgDropQMeasure, is at qosAlgDropQThreshold, packets currently at the head of the queue are dropped to make room for the new packet to be enqueued at the tail of the queue. The randomDrop(4) algorithm is described as follows: on packet arrival, an algorithm is executed which may randomly drop the packet, or drop other packet(s) from the queue in its place. The specifics of the algorithm may be proprietary. For this algorithm, qosAlgDropSpecific points to a qosRandomDropEntry that describes the algorithm. For this algorithm, qosAlgQThreshold is understood to be the absolute maximum size of the queue and additional parameters are described in qosRandomDropTable. The alwaysDrop(5) algorithm always drops packets. In this case, the other configuration values in this Entry are not meaningful; The queue is not used, therefore, qosAlgDropNext, qosAlgDropQMeasure, and qosAlgDropSpecific should be all set to zeroDotZero. The mQDrop(6) algorithm measures multiple queues for the drop algorithm. The queues measured are represented by having qosAlgDropQMeasure referencing a qosMQAlgDropEntry. Each of the chained qosMQAlgDropEntry is used to describe the drop algorithm for one of the measured queues." ::= { qosAlgDropEntry 2 } qosAlgDropNext OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "This selects the next diffserv functional datapath element to handle traffic for this data path. The value zeroDotZero in this attribute indicates no further Diffserv treatment is performed on traffic of this datapath. Any other value must point to a valid (pre-existing) instance of one of: qosClfrEntry qosMeterEntry qosActionEntry qosAlgDropEntry qosQEntry. When qosAlgDropType is alwaysDrop(5), this attribute is Ignored." [Page 57] DiffServ QoS Policy Information Base March 2002 DEFVAL { zeroDotZero } ::= { qosAlgDropEntry 3 } qosAlgDropQMeasure OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "Points to a PRI to indicate the queues that a drop algorithm is to monitor when deciding whether to drop a packet. For alwaysDrop(5), this attribute should be zeroDotZero. For tailDrop(2), headDrop(3), randomDrop(4), this should point to an entry in the qosQTable. For mQDrop(6), this should point to a qosMQAlgDropEntry that Describe one of the queues being measured for multiple queue dropper. The PRI pointed to must exist prior to installing this dropper element." ::= { qosAlgDropEntry 4 } qosAlgDropQThreshold OBJECT-TYPE SYNTAX Unsigned32 UNITS "Bytes" STATUS current DESCRIPTION "A threshold on the depth in bytes of the queue being measured at which a trigger is generated to the drop- ping algorithm, unless qosAlgDropType is alwaysDrop(5) where this attribute is ignored. For the tailDrop(2) or headDrop(3) algorithms, this represents the depth of the queue, pointed to by qosAlgDropQMeasure, at which the drop action will take place. Other algorithms will need to define their own semantics for this threshold." ::= { qosAlgDropEntry 5 } qosAlgDropSpecific OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "Points to a table entry that provides further detail regarding a drop algorithm. The PRI pointed to must exist prior to installing this dropper element. Entries with qosAlgDropType equal to other(1) must have this point to an instance of a PRC defined in another PIB module. Entries with qosAlgDropType equal to random- [Page 58] DiffServ QoS Policy Information Base March 2002 Drop(4) must have this point to an entry in qosRandomDropTable. Entries with qosAlgDropType equal to mQDrop(6) can use this attribute to reference parameters that is used by all the queues of the multiple queues being measured. For all other algorithms, this should take the value zeroDotZero." ::= { qosAlgDropEntry 6 } -- -- Multiple Queue Algorithmic Drop Table -- -- Entries of this table should be referenced by qosAlgDropQMeasure -- when qosAlgDropType is mQDrop(6) for droppers measuring multiple -- queues for its drop algorithm. -- Each entry of the table is used to describe the drop algorithm -- for a single queue within the multiple queues being measured. -- -- Entries of this table, qosMQAlgDropEntry, is extended from -- qosAlgDropEntry, with usage of corresponding parameters the same -- except: -- qosMQAlgDropNext is used to point to the next diffserv -- functional data path element when the packet is not dropped. -- qosMQAlgDropExceedNext is used to point to the next -- qosMQAlgDropEntry for chaining together the multiple -- qosMQAlgDropEntry's for the multiple queues being measured. -- qosMQAlgDropTable OBJECT-TYPE SYNTAX SEQUENCE OF QosMQAlgDropEntry PIB-ACCESS install STATUS current DESCRIPTION "The multiple queue algorithmic drop table contains entries describing each queue being measured for the multiple queue algorithmic dropper." ::= { qosPolicyClasses 10 } qosMQAlgDropEntry OBJECT-TYPE SYNTAX QosMQAlgDropEntry STATUS current DESCRIPTION "An entry describes a process that drops packets according to some algorithm. Each entry is used for each of the multiple queues being measured. Each entry extends the basic qosAlgDropEntry with adding of a qosMQAlgDropExceedNext attribute. Further details of the algorithm type are to be found in [Page 59] DiffServ QoS Policy Information Base March 2002 qosAlgDropType and with more detail parameter entry pointed to by qosMQAlgDropSpecific when necessary." EXTENDS { qosAlgDropEntry } UNIQUENESS { qosMQAlgDropExceedNext } ::= { qosMQAlgDropTable 1 } QosMQAlgDropEntry ::= SEQUENCE { qosMQAlgDropExceedNext Prid } qosMQAlgDropExceedNext OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "Used for linking of multiple qosMQAlgDropEntry for mQDrop. A value of zeroDotZero indicates this is the last of a chain of qosMQAlgDropEntry." DEFVAL { zeroDotZero } ::= { qosMQAlgDropEntry 1 } -- -- Random Drop Table -- qosRandomDropTable OBJECT-TYPE SYNTAX SEQUENCE OF QosRandomDropEntry PIB-ACCESS install STATUS current DESCRIPTION "The random drop table contains entries describing a process that drops packets randomly. Entries in this table is intended to be pointed to by qosAlgDropSpecific." REFERENCE "[MODEL] section 7.1.3" ::= { qosPolicyClasses 11 } qosRandomDropEntry OBJECT-TYPE SYNTAX QosRandomDropEntry STATUS current DESCRIPTION "An entry describes a process that drops packets according to a random algorithm." PIB-INDEX { qosRandomDropPrid } UNIQUENESS { qosRandomDropMinThreshBytes, qosRandomDropMinThreshPkts, qosRandomDropMaxThreshBytes, qosRandomDropMaxThreshPkts, qosRandomDropProbMax, [Page 60] DiffServ QoS Policy Information Base March 2002 qosRandomDropWeight, qosRandomDropSamplingRate } ::= { qosRandomDropTable 1 } QosRandomDropEntry ::= SEQUENCE { qosRandomDropPrid InstanceId, qosRandomDropMinThreshBytes Unsigned32, qosRandomDropMinThreshPkts Unsigned32, qosRandomDropMaxThreshBytes Unsigned32, qosRandomDropMaxThreshPkts Unsigned32, qosRandomDropProbMax Unsigned32, qosRandomDropWeight Unsigned32, qosRandomDropSamplingRate Unsigned32 } qosRandomDropPrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosRandomDropEntry 1 } qosRandomDropMinThreshBytes OBJECT-TYPE SYNTAX Unsigned32 UNITS "bytes" STATUS current DESCRIPTION "The average queue depth in bytes, beyond which traffic has a non-zero probability of being dropped." ::= { qosRandomDropEntry 2 } qosRandomDropMinThreshPkts OBJECT-TYPE SYNTAX Unsigned32 UNITS "packets" STATUS current DESCRIPTION "The average queue depth in packets, beyond which traffic has a non-zero probability of being dropped." ::= { qosRandomDropEntry 3 } qosRandomDropMaxThreshBytes OBJECT-TYPE SYNTAX Unsigned32 UNITS "bytes" STATUS current DESCRIPTION "The average queue depth beyond which traffic has a probability indicated by qosRandomDropProbMax of being dropped [Page 61] DiffServ QoS Policy Information Base March 2002 or marked. Note that this differs from the physical queue limit, which is stored in qosAlgDropQThreshold." ::= { qosRandomDropEntry 4 } qosRandomDropMaxThreshPkts OBJECT-TYPE SYNTAX Unsigned32 UNITS "packets" STATUS current DESCRIPTION "The average queue depth beyond which traffic has a probability indicated by qosRandomDropProbMax of being dropped or marked. Note that this differs from the physical queue limit, which is stored in qosAlgDropQThreshold." ::= { qosRandomDropEntry 5 } qosRandomDropProbMax OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "The worst case random drop probability, expressed in drops per thousand packets. For example, if every packet may be dropped in the worst case (100%), this has the value 1000. Alternatively, if in the worst case one percent (1%) of traffic may be dropped, it has the value 10." ::= { qosRandomDropEntry 6 } qosRandomDropWeight OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "The weighting of past history in affecting the Exponentially Weighted Moving Average function which calculates the current average queue depth. The equation uses qosRandomDropWeight/MaxValue as the coefficient for the new sample in the equation, and (MaxValue - qosRandomDropWeight)/MaxValue as the coefficient of the old value, where, MaxValue is determined via capability reported by the PEP. Implementations may further limit the values of qosRandomDropWeight via the capability tables." ::= { qosRandomDropEntry 7 } qosRandomDropSamplingRate OBJECT-TYPE SYNTAX Unsigned32 STATUS current [Page 62] DiffServ QoS Policy Information Base March 2002 DESCRIPTION "The number of times per second the queue is sampled for queue average calculation. A value of zero means the queue is sampled approximately each time a packet is enqueued (or dequeued)." ::= { qosRandomDropEntry 8 } [Page 63] DiffServ QoS Policy Information Base March 2002 -- -- Queue Table -- -- -- An entry of qosQTable represents a FIFO queue diffserv -- functional data path element as described in [MODEL] section -- 7.1.1. -- Notice the specification of scheduling parameters for a queue -- as part of the input to a scheduler functional data path -- element as described in [MODEL] section 7.1.2. This allows -- building of hierarchical queuing/scheduling. -- A queue therefore is parameterized by: -- 1. Which scheduler will service this queue, qosQNext. -- 2. How the scheduler will service this queue, with respect -- to all the other queues the same scheduler needs to service, -- qosQMinRate and qosQMaxRate. -- -- Notice one or more upstream diffserv functional data path element -- may share, point to, a qosQTable entry as described in [MODEL] -- section 7.1.1. -- qosQTable OBJECT-TYPE SYNTAX SEQUENCE OF QosQEntry PIB-ACCESS install STATUS current DESCRIPTION "The Queue Table enumerates the queues." ::= { qosPolicyClasses 12 } qosQEntry OBJECT-TYPE SYNTAX QosQEntry STATUS current DESCRIPTION "An entry in the Queue Table describes a single queue as a functional data path element." PIB-INDEX { qosQPrid } UNIQUENESS { qosQNext, qosQMinRate, qosQMaxRate } ::= { qosQTable 1 } QosQEntry ::= SEQUENCE { qosQPrid InstanceId, qosQNext Prid, qosQMinRate Prid, qosQMaxRate Prid } [Page 64] DiffServ QoS Policy Information Base March 2002 qosQPrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosQEntry 1 } qosQNext OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "This selects the next diffserv scheduler. This must point to a qosSchedulerEntry. A value of zeroDotZero in this attribute indicates an incomplete qosQEntry instance. In such a case, the entry has no operational effect, since it has no parameters to give it meaning." ::= { qosQEntry 2 } qosQMinRate OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "This Prid indicates the entry in qosMinRateTable the scheduler, pointed to by qosQNext, should use to service this queue. If this value is zeroDotZero, then minimum rate and priority is unspecified. If this value is not zeroDotZero then the instance pointed to must exist prior to installing this entry." ::= { qosQEntry 3 } qosQMaxRate OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "This Prid indicates the entry in qosMaxRateTable the scheduler, pointed to by qosQNext, should use to service this queue. If this value is zeroDotZero, then the maximum rate is the line speed of the interface. If this value is not zeroDotZero then the instance pointed to must exist prior to installing this entry." ::= { qosQEntry 4 } [Page 65] DiffServ QoS Policy Information Base March 2002 -- -- Scheduler Table -- -- -- The Scheduler Table is used for representing packet schedulers: -- it provides flexibility for multiple scheduling algorithms, each -- servicing multiple queues, to be used on the same -- logical/physical interface of a data path. -- -- Notice the servicing parameters the scheduler uses is -- specified by each of its upstream functional data path elements, -- queues or schedulers of this PIB. -- The coordination and coherency between the servicing parameters -- of the scheduler's upstream functional data path elements must -- be maintained for the scheduler to function correctly. -- -- The qosSchedulerMinRate and qosSchedulerMaxRate attributes are -- used for specifying the servicing parameters for output of a -- scheduler when its downstream functional data path element -- is another scheduler. -- This is used for building hierarchical queue/scheduler. -- -- More discussion of the scheduler functional data path element -- is in [MODEL] section 7.1.2. -- qosSchedulerTable OBJECT-TYPE SYNTAX SEQUENCE OF QosSchedulerEntry PIB-ACCESS install STATUS current DESCRIPTION "The Scheduler Table enumerates packet schedulers. Multiple scheduling algorithms can be used on a given datapath, with each algorithm described by one qosSchedulerEntry." REFERENCE "[MODEL] section 7.1.2" ::= { qosPolicyClasses 13 } qosSchedulerEntry OBJECT-TYPE SYNTAX QosSchedulerEntry STATUS current DESCRIPTION "An entry in the Scheduler Table describing a single instance of a scheduling algorithm." PIB-INDEX { qosSchedulerPrid } UNIQUENESS { qosSchedulerNext, qosSchedulerMethod, qosSchedulerMinRate, qosSchedulerMaxRate } ::= { qosSchedulerTable 1 } [Page 66] DiffServ QoS Policy Information Base March 2002 QosSchedulerEntry ::= SEQUENCE { qosSchedulerPrid InstanceId, qosSchedulerNext Prid, qosSchedulerMethod OBJECT IDENTIFIER, qosSchedulerMinRate Prid, qosSchedulerMaxRate Prid } qosSchedulerPrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosSchedulerEntry 1 } qosSchedulerNext OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "This selects the next diffserv functional datapath element to handle traffic for this data path. This attribute normally have a value of zeroDotZero to indicate no further Diffserv treatment is performed on traffic of this datapath. The use of zeroDotZero is the normal usage for the last functional datapath element. Any value other than zeroDotZero must point to a valid (pre-existing) instance of one of: qosSchedulerEntry qosQEntry, or: qosClfrEntry qosMeterEntry qosActionEntry qosAlgDropEntry This points to another qosSchedulerEntry for implementation of multiple scheduler methods for the same data path, and for implementation of hierarchical schedulers." DEFVAL { zeroDotZero } ::= { qosSchedulerEntry 2 } qosSchedulerMethod OBJECT-TYPE SYNTAX OBJECT IDENTIFIER STATUS current DESCRIPTION [Page 67] DiffServ QoS Policy Information Base March 2002 "The scheduling algorithm used by this Scheduler. Standard values for generic algorithms: qosSchedulerPriority, qosSchedulerWRR, qosSchedulerWFQ are specified in this PIB. Additional values may be further specified in other PIBs. A value of zeroDotZero indicates this is unknown." REFERENCE "[MODEL] section 7.1.2" ::= { qosSchedulerEntry 3 } qosSchedulerMinRate OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "This Prid indicates the entry in qosMinRateTable which indicates the priority or minimum output rate from this scheduler. This attribute is used only when there is more than one level of scheduler. When it has the value zeroDotZero, it indicates that no Minimum rate or priority is imposed." DEFVAL { zeroDotZero } ::= { qosSchedulerEntry 4 } qosSchedulerMaxRate OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "This Prid indicates the entry in qosMaxRateTable which indicates the maximum output rate from this scheduler. When more than one maximum rate applies (e.g. a multi-rate shaper is used), it points to the first of the rate entries. This attribute is only used when there is more than one level of scheduler. When it has the value zeroDotZero, it indicates that no Maximum rate is imposed." DEFVAL { zeroDotZero } ::= { qosSchedulerEntry 5 } [Page 68] DiffServ QoS Policy Information Base March 2002 -- -- Minimum Rate Parameters Table -- -- The parameters used by a scheduler for its inputs or outputs are -- maintained separately from the Queue or Scheduler table entries -- for reusability reasons and so that they may be used by both -- queues and schedulers. This follows the approach for separation -- of data path elements from parameterization that is used -- throughout this PIB. -- Use of these Minimum Rate Parameter Table entries by Queues and -- Schedulers allows the modeling of hierarchical scheduling -- systems. -- -- Specifically, a Scheduler has one or more inputs and one output. -- Any queue feeding a scheduler, or any scheduler which feeds a -- second scheduler, might specify a minimum transfer rate by -- pointing to a Minimum Rate Parameter Table entry. -- -- The qosMinRatePriority/Abs/Rel attributes are used as -- parameters to the work-conserving portion of a scheduler: -- "work-conserving" implies that the scheduler can continue to emit -- data as long as there is data available at its input(s). This -- has the effect of guaranteeing a certain priority relative to -- other scheduler inputs and/or a certain minimum proportion of the -- available output bandwidth. Properly configured, this means a -- certain minimum rate, which may be exceeded should traffic be -- available should there be spare bandwidth after all other classes -- have had opportunities to consume their own minimum rates. -- qosMinRateTable OBJECT-TYPE SYNTAX SEQUENCE OF QosMinRateEntry PIB-ACCESS install STATUS current DESCRIPTION "The Minimum Rate Table enumerates individual sets of scheduling parameter that can be used/reused by Queues and Schedulers." ::= { qosPolicyClasses 14 } qosMinRateEntry OBJECT-TYPE SYNTAX QosMinRateEntry STATUS current DESCRIPTION "An entry in the Minimum Rate Table describes a single set of scheduling parameter for use by queues and schedulers." PIB-INDEX { qosMinRatePrid } UNIQUENESS { qosMinRatePriority, qosMinRateAbsolute, qosMinRateRelative } ::= { qosMinRateTable 1 } [Page 69] DiffServ QoS Policy Information Base March 2002 QosMinRateEntry ::= SEQUENCE { qosMinRatePrid InstanceId, qosMinRatePriority Unsigned32, qosMinRateAbsolute Unsigned32, qosMinRateRelative Unsigned32 } qosMinRatePrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosMinRateEntry 1 } qosMinRatePriority OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "The priority of this input to the associated scheduler, relative to the scheduler's other inputs. Higher Priority value indicates the associated queue/scheduler will get service first before others with lower Priority values." ::= { qosMinRateEntry 2 } qosMinRateAbsolute OBJECT-TYPE SYNTAX Unsigned32 UNITS "kilobits per second" STATUS current DESCRIPTION "The minimum absolute rate, in kilobits/sec, that a downstream scheduler element should allocate to this queue. If the value is zero, then there is effectively no minimum rate guarantee. If the value is non-zero, the scheduler will assure the servicing of this queue to at least this rate. Note that this attribute's value is coupled to that of qosMinRateRelative: changes to one will affect the value of the other. [IFMIB] defines ifSpeed as Gauge32 in units of bits per second, and ifHighSpeed as Gauge32 in units of 1,000,000 bits per second. This yields the following equations: RateRelative = [ (RateAbsolute * 1000) / ifSpeed ] * 1,000 Where, 1000 is for converting kbps used by RateAbsolute to bps used by ifSpeed, 1,000 is for 'in units of 1/1,000 of 1' for [Page 70] DiffServ QoS Policy Information Base March 2002 RateRelative. or, if appropriate: RateRelative = { [ (RateAbsolute * 1000) / 1,000,000 ] / ifHIghSpeed } * 1,000 Where, 1000 and 1,000,000 is for converting kbps used by RateAbsolute to 1 million bps used by ifHighSpeed, 1,000 is for 'in units of 1/1,000 of 1' for RateRelative." REFERENCE "ifSpeed, ifHighSpeed from [IFMIB]" ::= { qosMinRateEntry 3 } qosMinRateRelative OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "The minimum rate that a downstream scheduler element should allocate to this queue, relative to the max- imum rate of the interface as reported by ifSpeed or ifHighSpeed, in units of 1/1,000 of 1. If the value is zero, then there is effectively no minimum rate guarantee. If the value is non-zero, the scheduler will assure the servicing of this queue to at least this rate. Note that this attribute's value is coupled to that of qosMinRateAbsolute: changes to one will affect the value of the other. [IFMIB] defines ifSpeed as Gauge32 in units of bits per second, and ifHighSpeed as Gauge32 in units of 1,000,000 bits per second. This yields the following equations: RateRelative = [ (RateAbsolute * 1000) / ifSpeed ] * 1,000 Where, 1000 is for converting kbps used by RateAbsolute to bps used by ifSpeed, 1,000 is for 'in units of 1/1,000 of 1' for RateRelative. or, if appropriate: RateRelative = { [ (RateAbsolute * 1000) / 1,000,000 ] / ifHIghSpeed } * 1,000 Where, 1000 and 1,000,000 is for converting kbps used by RateAbsolute to 1 million bps used by ifHighSpeed, 1,000 is for 'in units of 1/1,000 of 1' for RateRelative." REFERENCE [Page 71] DiffServ QoS Policy Information Base March 2002 "ifSpeed, ifHighSpeed from [IFMIB]" ::= { qosMinRateEntry 4 } -- -- Maximum Rate Parameters Table -- -- The parameters used by a scheduler for its inputs or outputs are -- maintained separately from the Queue or Scheduler table entries -- for reusability reasons and so that they may be used by both -- queues and schedulers. This follows the approach for separation -- of data path elements from parameterization that is used -- throughout this MIB. -- Use of these Maximum Rate Parameter Table entries by Queues and -- Schedulers allows the modeling of hierarchical scheduling -- systems. -- -- Specifically, a Scheduler has one or more inputs and one output. -- Any queue feeding a scheduler, or any scheduler which feeds a -- second scheduler, might specify a maximum transfer rate by -- pointing to a Maximum Rate Parameter Table entry. Multi-rate -- shapers, such as a Dual Leaky Bucket algorithm, specify their -- rates using multiple Maximum Rate Parameter Entries with the same -- qosMaxRateId but different qosMaxRateLevels. -- -- The qosMaxRateLevel/Abs/Rel attributes are used as -- parameters to the non-work-conserving portion of a scheduler: -- non-work-conserving implies that the scheduler may sometimes not -- emit a packet, even if there is data available at its input(s). -- This has the effect of limiting the servicing of the -- queue/scheduler input or output, in effect performing shaping of -- the packet stream passing through the queue/scheduler, as -- described in the Informal Differentiated Services Model -- section 7.2. -- qosMaxRateTable OBJECT-TYPE SYNTAX SEQUENCE OF QosMaxRateEntry PIB-ACCESS install STATUS current DESCRIPTION "The Maximum Rate Table enumerates individual sets of scheduling parameter that can be used/reused by Queues and Schedulers." ::= { qosPolicyClasses 15 } qosMaxRateEntry OBJECT-TYPE SYNTAX QosMaxRateEntry STATUS current DESCRIPTION "An entry in the Maximum Rate Table describes a single set of scheduling parameter for use by [Page 72] DiffServ QoS Policy Information Base March 2002 queues and schedulers." PIB-INDEX { qosMaxRatePrid } UNIQUENESS { qosMaxRateId, qosMaxRateLevel, qosMaxRateAbsolute, qosMaxRateRelative, qosMaxRateThreshold } ::= { qosMaxRateTable 1 } QosMaxRateEntry ::= SEQUENCE { qosMaxRatePrid InstanceId, qosMaxRateId Unsigned32, qosMaxRateLevel Unsigned32, qosMaxRateAbsolute Unsigned32, qosMaxRateRelative Unsigned32, qosMaxRateThreshold BurstSize } qosMaxRatePrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosMaxRateEntry 1 } qosMaxRateId OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "An index used together with qosMaxRateId for representing a multi-rate shaper. This attribute is used for associating all the rate attributes of a multi-rate shaper. Each qosMaxRateEntry of a multi-rate shaper must have the same value in this attribute. The different rates of a multi-rate shaper is identified using qosMaxRateLevel. This attribute uses the value of zero to indicate this attribute is not used, for single rate shaper." DEFVAL { 0 } ::= { qosMaxRateEntry 2 } qosMaxRateLevel OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "An index that indicates which level of a multi-rate shaper is being given its parameters. A multi-rate shaper has some number of rate levels. Frame Relay's dual rate specification refers to a 'committed' and an 'excess' rate; ATM's dual rate specification refers to a 'mean' and a 'peak' rate. This table [Page 73] DiffServ QoS Policy Information Base March 2002 is generalized to support an arbitrary number of rates. The committed or mean rate is level 1, the peak rate (if any) is the highest level rate configured, and if there are other rates they are distributed in monotonically increasing order between them. When the entry is used for a single rate shaper, this attribute contains a value of zero." DEFVAL { 0 } ::= { qosMaxRateEntry 3 } qosMaxRateAbsolute OBJECT-TYPE SYNTAX Unsigned32 UNITS "kilobits per second" STATUS current DESCRIPTION "The maximum rate in kilobits/sec that a downstream scheduler element should allocate to this queue. If the value is zero, then there is effectively no max- imum rate limit and that the scheduler should attempt to be work-conserving for this queue. If the value is non-zero, the scheduler will limit the servicing of this queue to, at most, this rate in a non-work- conserving manner. Note that this attribute's value is coupled to that of qosMaxRateRelative: changes to one will affect the value of the other. [IFMIB] defines ifSpeed as Gauge32 in units of bits per second, and ifHighSpeed as Gauge32 in units of 1,000,000 bits per second. This yields the following equations: RateRelative = [ (RateAbsolute * 1000) / ifSpeed ] * 1,000 Where, 1000 is for converting kbps used by RateAbsolute to bps used by ifSpeed, 1,000 is for 'in units of 1/1,000 of 1' for RateRelative. or, if appropriate: RateRelative = { [ (RateAbsolute * 1000) / 1,000,000 ] / ifHIghSpeed } * 1,000 Where, 1000 and 1,000,000 is for converting kbps used by RateAbsolute to 1 million bps used by ifHighSpeed, 1,000 is for 'in units of 1/1,000 of 1' for RateRelative." ::= { qosMaxRateEntry 4 } qosMaxRateRelative OBJECT-TYPE SYNTAX Unsigned32 [Page 74] DiffServ QoS Policy Information Base March 2002 STATUS current DESCRIPTION "The maximum rate that a downstream scheduler element should allocate to this queue, relative to the max- imum rate of the interface as reported by ifSpeed or ifHighSpeed, in units of 1/1,000 of 1. If the value is zero, then there is effectively no maximum rate limit and the scheduler should attempt to be work- conserving for this queue. If the value is non-zero, the scheduler will limit the servicing of this queue to, at most, this rate in a non-work-conserving manner. Note that this attribute's value is coupled to that of qosMaxRateAbsolute: changes to one will affect the value of the other. [IFMIB] defines ifSpeed as Gauge32 in units of bits per second, and ifHighSpeed as Gauge32 in units of 1,000,000 bits per second. This yields the following equations: RateRelative = [ (RateAbsolute * 1000) / ifSpeed ] * 1,000 Where, 1000 is for converting kbps used by RateAbsolute to bps used by ifSpeed, 1,000 is for 'in units of 1/1,000 of 1' for RateRelative. or, if appropriate: RateRelative = { [ (RateAbsolute * 1000) / 1,000,000 ] / ifHIghSpeed } * 1,000 Where, 1000 and 1,000,000 is for converting kbps used by RateAbsolute to 1 million bps used by ifHighSpeed, 1,000 is for 'in units of 1/1,000 of 1' for RateRelative." REFERENCE "ifSpeed, ifHighSpeed from [IFMIB]" ::= { qosMaxRateEntry 5 } qosMaxRateThreshold OBJECT-TYPE SYNTAX BurstSize UNITS "Bytes" STATUS current DESCRIPTION "The number of bytes of queue depth at which the rate of a multi-rate scheduler will increase to the next output rate. In the last PRI for such a shaper, this threshold is ignored and by convention is zero." REFERENCE "Adaptive Rate Shaper, RFC 2963" ::= { qosMaxRateEntry 6 } [Page 75] DiffServ QoS Policy Information Base March 2002 -- -- Parameters Section -- -- The Parameters Section defines parameter objects that can be used -- for specific attributes defined in the PIB PRCs. qosTBParameters OBJECT IDENTIFIER ::= { qosPolicyParameters 1 } qosSchedulerParameters OBJECT IDENTIFIER ::= { qosPolicyParameters 2 } -- -- Token Bucket Type Parameters -- qosTBParamSimpleTokenBucket OBJECT-IDENTITY STATUS current DESCRIPTION "This value indicates the use of a Two Parameter Token Bucket as described in [MODEL] section 5.2.3." REFERENCE "[MODEL] sections 5 and 7.1.2" ::= { qosTBParameters 1 } qosTBParamAvgRate OBJECT-IDENTITY STATUS current DESCRIPTION "This value indicates the use of an Average Rate Meter as described in [MODEL] section 5.2.1." REFERENCE "[MODEL] sections 5 and 7.1.2" ::= { qosTBParameters 2 } qosTBParamSrTCMBlind OBJECT-IDENTITY STATUS current DESCRIPTION "This value indicates the use of Single Rate Three Color Marker Metering as defined by RFC 2697, with `Color Blind' mode as described by the RFC." REFERENCE "[MODEL] sections 5 and 7.1.2" ::= { qosTBParameters 3 } qosTBParamSrTCMAware OBJECT-IDENTITY STATUS current DESCRIPTION "This value indicates the use of Single Rate Three Color Marker Metering as defined by RFC 2697, with `Color Aware' mode as described by the RFC." REFERENCE [Page 76] DiffServ QoS Policy Information Base March 2002 "[MODEL] sections 5 and 7.1.2" ::= { qosTBParameters 4 } qosTBParamTrTCMBlind OBJECT-IDENTITY STATUS current DESCRIPTION "This value indicates the use of Two Rate Three Color Marker Metering as defined by RFC 2698, with `Color Blind' mode as described by the RFC." REFERENCE "[MODEL] sections 5 and 7.1.2" ::= { qosTBParameters 5 } qosTBParamTrTCMAware OBJECT-IDENTITY STATUS current DESCRIPTION "This value indicates the use of Two Rate Three Color Marker Metering as defined by RFC 2698, with `Color Aware' mode as described by the RFC." REFERENCE "[MODEL] sections 5 and 7.1.2" ::= { qosTBParameters 6 } qosTBParamTswTCM OBJECT-IDENTITY STATUS current DESCRIPTION "This value indicates the use of Time Sliding Window Three Color Marker Metering as defined by RFC 2859." REFERENCE "[MODEL] sections 5 and 7.1.2" ::= { qosTBParameters 7 } -- -- Scheduler Method Parameters -- qosSchedulerPriority OBJECT-IDENTITY STATUS current DESCRIPTION "For use with qosSchedulerMethod and qosIfSchedulingCapsServiceDisc to indicate Priority scheduling method, defined as an algorithm in which the presence of data in a queue or set of queues absolutely precludes dequeue from another queue or set of queues. Notice attributes from qosMinRateEntry of the queues/schedulers feeding this scheduler are used when determining the next packet to schedule." REFERENCE "[MODEL] section 7.1.2" ::= { qosSchedulerParameters 1 } [Page 77] DiffServ QoS Policy Information Base March 2002 qosSchedulerWRR OBJECT-IDENTITY STATUS current DESCRIPTION "For use with qosSchedulerMethod and qosIfSchedulingCapsServiceDisc to indicate Weighted Round Robin scheduling method, defined as any algorithm in which a set of queues are visited in a fixed order, and varying amounts of traffic are removed from each queue in turn to implement an average output rate by class. Notice attributes from qosMinRateEntry of the queues/schedulers feeding this scheduler are used when determining the next packet to schedule." REFERENCE "[MODEL] section 7.1.2" ::= { qosSchedulerParameters 2 } qosSchedulerWFQ OBJECT-IDENTITY STATUS current DESCRIPTION "For use with qosSchedulerMethod and qosIfSchedulingCapsServiceDisc to indicate Weighted Fair Queueing scheduling method, defined as any algorithm in which a set of queues are conceptually visited in some order, to implement an average output rate by class. Notice attributes from qosMinRateEntry of the queues/schedulers feeding this scheduler are used when determining the next packet to schedule." REFERENCE "[MODEL] section 7.1.2" ::= { qosSchedulerParameters 3 } -- -- Conformance Section -- qosPolicyPibCompliances OBJECT IDENTIFIER ::= { qosPolicyPibConformance 1 } qosPolicyPibGroups OBJECT IDENTIFIER ::= { qosPolicyPibConformance 2 } qosPolicyPibCompliance MODULE-COMPLIANCE STATUS current DESCRIPTION "Describes the requirements for conformance to the QoS Policy PIB." [Page 78] DiffServ QoS Policy Information Base March 2002 MODULE DIFFSERV-PIB -- this module MANDATORY-GROUPS { qosPibDataPathGroup, qosPibClfrGroup, qosPibClfrElementGroup, qosPibActionGroup, qosPibAlgDropGroup, qosPibQGroup, qosPibSchedulerGroup, qosPibMinRateGroup, qosPibMaxRateGroup } GROUP qosPibMeterGroup DESCRIPTION "This group is mandatory for devices that implement metering functions." GROUP qosPibTBParamGroup DESCRIPTION "This group is mandatory for devices that implement token-bucket metering functions." GROUP qosPibDscpMarkActGroup DESCRIPTION "This group is mandatory for devices that implement DSCP-Marking functions." GROUP qosPibMQAlgDropGroup DESCRIPTION "This group is mandatory for devices that implement Multiple Queue Measured Algorithmic Drop functions." GROUP qosPibRandomDropGroup DESCRIPTION "This group is mandatory for devices that implement Random Drop functions." OBJECT qosClfrId PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosClfrElementClfrId PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." [Page 79] DiffServ QoS Policy Information Base March 2002 OBJECT qosClfrElementPrecedence PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosClfrElementNext PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosClfrElementSpecific PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosMeterSucceedNext PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosMeterFailNext PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosMeterSpecific PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosTBParamType PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosTBParamRate PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosTBParamBurstSize PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." [Page 80] DiffServ QoS Policy Information Base March 2002 OBJECT qosTBParamInterval PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosActionNext PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosActionSpecific PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosAlgDropType PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosAlgDropNext PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosAlgDropQMeasure PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosAlgDropQThreshold PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosAlgDropSpecific PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosRandomDropMinThreshBytes PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." [Page 81] DiffServ QoS Policy Information Base March 2002 OBJECT qosRandomDropMinThreshPkts PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosRandomDropMaxThreshBytes PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosRandomDropMaxThreshPkts PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosRandomDropProbMax PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosRandomDropWeight PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosRandomDropSamplingRate PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosQNext PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosQMinRate PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosQMaxRate PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." [Page 82] DiffServ QoS Policy Information Base March 2002 OBJECT qosSchedulerNext PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosSchedulerMethod PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosSchedulerMinRate PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosSchedulerMaxRate PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosMinRatePriority PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosMinRateAbsolute PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosMinRateRelative PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosMaxRateId PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosMaxRateLevel PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." [Page 83] DiffServ QoS Policy Information Base March 2002 OBJECT qosMaxRateAbsolute PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosMaxRateRelative PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosMaxRateThreshold PIB-MIN-ACCESS notify DESCRIPTION "Install support is not required." ::= { qosPibCompliances 1 } qosPibDataPathGroup OBJECT-GROUP OBJECTS { qosDataPathIfName, qosDataPathRoles, qosDataPathDirection, qosDataPathStart } STATUS current DESCRIPTION "The Data Path Group defines the PIB Objects that describe a data path." ::= { qosPolicyPibGroups 1 } qosPibClfrGroup OBJECT-GROUP OBJECTS { qosClfrId } STATUS current DESCRIPTION "The Classifier Group defines the PIB Objects that describe a generic classifier." ::= { qosPolicyPibGroups 2 } qosPibClfrElementGroup OBJECT-GROUP OBJECTS { qosClfrElementClfrId, qosClfrElementPrecedence, qosClfrElementNext, qosClfrElementSpecific } STATUS current DESCRIPTION "The Classifier Group defines the PIB Objects that describe a generic classifier." [Page 84] DiffServ QoS Policy Information Base March 2002 ::= { qosPolicyPibGroups 3 } qosPibMeterGroup OBJECT-GROUP OBJECTS { qosMeterSucceedNext, qosMeterFailNext, qosMeterSpecific } STATUS current DESCRIPTION "The Meter Group defines the objects used in describ- ing a generic meter element." ::= { qosPolicyPibGroups 4 } qosPibTBParamGroup OBJECT-GROUP OBJECTS { qosTBParamType, qosTBParamRate, qosTBParamBurstSize, qosTBParamInterval } STATUS current DESCRIPTION "The Token-Bucket Parameter Group defines the objects used in describing a single-rate token bucket meter element." ::= { qosPolicyPibGroups 5 } qosPibActionGroup OBJECT-GROUP OBJECTS { qosActionNext, qosActionSpecific } STATUS current DESCRIPTION "The Action Group defines the objects used in describing a generic action element." ::= { qosPolicyPibGroups 6 } qosPibDscpMarkActGroup OBJECT-GROUP OBJECTS { qosDscpMarkActDscp } STATUS current DESCRIPTION "The DSCP Mark Action Group defines the objects used in describing a DSCP Marking Action element." ::= { qosPolicyPibGroups 7 } qosPibAlgDropGroup OBJECT-GROUP OBJECTS { qosAlgDropType, qosAlgDropNext, qosAlgDropQMeasure, qosAlgDropQThreshold, [Page 85] DiffServ QoS Policy Information Base March 2002 qosAlgDropSpecific } STATUS current DESCRIPTION "The Algorithmic Drop Group contains the objects that describe algorithmic dropper operation and configura- tion." ::= { qosPolicyPibGroups 8 } qosPibMQAlgDropGroup OBJECT-GROUP OBJECTS { qosMQAlgDropExceedNext } STATUS current DESCRIPTION "The Multiple Queue Measured Algorithmic Drop Group contains the objects that describe multiple queue measured algorithmic dropper operation and configuration." ::= { qosPolicyPibGroups 9 } qosPibRandomDropGroup OBJECT-GROUP OBJECTS { qosRandomDropMinThreshBytes, qosRandomDropMinThreshPkts, qosRandomDropMaxThreshBytes, qosRandomDropMaxThreshPkts, qosRandomDropProbMax, qosRandomDropWeight, qosRandomDropSamplingRate } STATUS current DESCRIPTION "The Random Drop Group augments the Algorithmic Drop Group for random dropper operation and configuration." ::= { qosPolicyPibGroups 10 } qosPibQGroup OBJECT-GROUP OBJECTS { qosQNext, qosQMinRate, qosQMaxRate } STATUS current DESCRIPTION "The Queue Group contains the objects that describe an interface type's queues." ::= { qosPolicyPibGroups 11 } qosPibSchedulerGroup OBJECT-GROUP OBJECTS { qosSchedulerNext, qosSchedulerMethod, qosSchedulerMinRate, qosSchedulerMaxRate [Page 86] DiffServ QoS Policy Information Base March 2002 } STATUS current DESCRIPTION "The Scheduler Group contains the objects that describe packet schedulers on interface types." ::= { qosPolicyPibGroups 12 } qosPibMinRateGroup OBJECT-GROUP OBJECTS { qosMinRatePriority, qosMinRateAbsolute, qosMinRateRelative } STATUS current DESCRIPTION "The Minimum Rate Group contains the objects that describe packet schedulers' parameters on interface types." ::= { qosPolicyPibGroups 13 } qosPibMaxRateGroup OBJECT-GROUP OBJECTS { qosMaxRateId, qosMaxRateLevel, qosMaxRateAbsolute, qosMaxRateRelative, qosMaxRateThreshold } STATUS current DESCRIPTION "The Maximum Rate Group contains the objects that describe packet schedulers' parameters on interface types." ::= { qosPolicyPibGroups 14 } END [Page 87] DiffServ QoS Policy Information Base March 2002 9. Acknowledgments This PIB builds on all the work that has gone into the Informal Management Model for Diffserv Routers and Management Information Base for the Differentiated Services Architecture. It has been developed with the active involvement of many people, but most notably Ravi Sahita and Walter Weiss. 10. Subject Category Considerations The numbering space used for the DiffServ PIB, as indicated by the SUBJECT-CATEGORIES clause, will be assigned by the Internet Assigned Numbers Authority (IANA). Notice the numbering space used by SUBJECT-CATEGORIES maps to the Client Type numbering space in [COPS- PR]. This relationship is detailed in section 7.1 of [SPPI]. Due to the fact that Client Type value of 1 has already been used by [COPS-RSVP], the numbering space for SUBJECT-CATEGORIES will need to start with the value of 2. Other PIB Modules may use the same SUBJECT-CATEGORIES as this DiffServ PIB Module. In such situations, PRC numbering space under a specific SUBJECT-CATEGORIES should be coordinated with existing PIB Modules using the same SUBJECT-CATEGORIES. 11. Security Considerations The information contained in a PIB when transported by the COPS protocol [COPS-PR] may be sensitive, and its function of provisioning a PEP requires that only authorized communication take place. The use of IPSEC between PDP and PEP, as described in [COPS], provides the necessary protection against these threats. 12. Intellectual Property Considerations The IETF is being notified of intellectual property rights claimed in regard to some or all of the specification contained in this document. For more information consult the online list of claimed rights. 13. RFC Editor Considerations Some IETF documents this document references are in the IESG last call stage. This document references them as internet drafts. Please use their corresponding RFC numbers prior to publishing of this document as a RFC. The referenced IETF documents are [FR-PIB], [MODEL], and [DS-MIB]. [Page 88] DiffServ QoS Policy Information Base March 2002 14. IANA Considerations This document standardizes a Policy Information Base (PIB) module, requesting an IANA assigned PIB number. 15. Authors' Addresses Michael Fine Cisco Systems, Inc. 170 West Tasman Drive San Jose, CA 95134-1706 USA Phone: +1 408 527 8218 Email: mfine@cisco.com Keith McCloghrie Cisco Systems, Inc. 170 West Tasman Drive San Jose, CA 95134-1706 USA Phone: +1 408 526 5260 Email: kzm@cisco.com John Seligson Nortel Networks, Inc. 4401 Great America Parkway Santa Clara, CA 95054 USA Phone: +1 408 495 2992 Email: jseligso@nortelnetworks.com Kwok Ho Chan Nortel Networks, Inc. 600 Technology Park Drive Billerica, MA 01821 USA Phone: +1 978 288 8175 Email: khchan@nortelnetworks.com Scott Hahn Intel 2111 NE 25th Avenue Hillsboro, OR 97124 USA Phone: +1 503 264 8231 Email: scott.hahn@intel.com Carol Bell Intel 2111 NE 25th Avenue Hillsboro, OR 97124 USA [Page 89] DiffServ QoS Policy Information Base March 2002 Phone: +1 503 264 8491 Email: carol.a.bell@intel.com Andrew Smith Allegro Networks 6399 San Ignacio Ave San Jose, CA 95119 andrew@allegronetworks.com Francis Reichmeyer PFN, Inc. University Park at MIT 26 Landsdowne Street Cambridge, MA 02139 Phone: +1 617 494 9980 Email: franr@pfn.com 16. References [COPS] Boyle, J., Cohen, R., Durham, D., Herzog, S., Rajan, R., and A. Sastry, "The COPS (Common Open Policy Service) Protocol" RFC 2748, January 2000. [COPS-PR] K. Chan, D. Durham, S. Gai, S. Herzog, K. McCloghrie, F. Reichmeyer, J. Seligson, A. Smith, R. Yavatkar, "COPS Usage for Policy Provisioning,", RFC 3084, March 2001 [SPPI] K. McCloghrie, M. Fine, J. Seligson, K. Chan, S. Hahn, R. Sahita, A. Smith, F. Reichmeyer, "Structure of Policy Provisioning Information", RFC 3159,August 2001. [DSARCH] M. Carlson, W. Weiss, S. Blake, Z. Wang, D. Black, and E. Davies, "An Architecture for Differentiated Services", RFC 2475, December 1998 [DSFIELD] K. Nichols, S. Blake, F. Baker, D. Black, "Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers", RFC 2474, December 1998. [Page 90] DiffServ QoS Policy Information Base March 2002 [FR-PIB] M. Fine, K. McCloghrie, J. Seligson, K. Chan, S. Hahn, R. Sahita, A. Smith, F. Reichmeyer, "Framework Policy Information Base", Internet Draft , January 2002. [RAP-FRAMEWORK] R. Yavatkar, D. Pendarakis, "A Framework for Policy-based Admission Control", RFC 2753, January 2000. [SNMP-SMI] K. McCloghrie, D. Perkins, J. Schoenwaelder, J. Case, M. Rose and S. Waldbusser, "Structure of Management Information Version 2 (SMIv2)", STD 58, RFC 2578, April 1999. [MODEL] Y. Bernet, S. Blake, D. Grossman, A. Smith "An Informal Management Model for Diffser Routers", Internet Draft , February 2001. [IFMIB] K. McCloghrie, F. Kastenholz, "The Interfaces Group MIB using SMIv2", RFC 2233, November 1997. [DS-MIB] F. Baker, K. Chan, A. Smith, "Management Information Base for the Differentiated Services Architecture", draft-ietf-diffserv-mib-16.txt, November 2001 [ACTQMGMT] V. Firoiu, M. Borden "A Study of Active Queue Management for Congestion Control", March 2000, In IEEE Infocom 2000, http://www.ieee-infocom.org/2000/papers/405.pdf [AQMROUTER] V.Misra, W.Gong, D.Towsley "Fluid-based analysis of a network of AQM routers supporting TCP flows with an application to RED", In SIGCOMM 2000, http://www.acm.org/sigcomm/sigcomm2000/conf/paper/ sigcomm2000-4-3.ps.gz [AF-PHB] J. Heinanen, F. Baker, W. Weiss, J. Wroclawski, "Assured Forwarding PHB Group.", RFC 2597, June 1999. [EF-PHB] V. Jacobson, K. Nichols, K. Poduri, "An Expedited Forwarding PHB." RFC 2598, June 1999. [INETADDRESS] [Page 91] DiffServ QoS Policy Information Base March 2002 Daniele, M., Haberman, B., Routhier, S., Schoenwaelder, J., "Textual Conventions for Internet Network Addresses.", RFC 2851, June 2000. [INTSERVMIB] F. Baker, J. Krawczyk, A. Sastry, "Integrated Services Management Information Base using SMIv2", RFC 2213, September 1997. [QUEUEMGMT] B. Braden et al., "Recommendations on Queue Management and Congestion Avoidance in the Internet", RFC 2309, April 1998. [RED93] "Random Early Detection", 1993. [SRTCM] J. Heinanen, R. Guerin, "A Single Rate Three Color Marker", RFC 2697, September 1999. [TRTCM] J. Heinanen, R. Guerin, "A Two Rate Three Color Marker", RFC 2698, September 1999. [TSWTCM] W. Fang, N. Seddigh, B. Nandy "A Time Sliding Window Three Colour Marker", RFC 2859, June 2000. [RFC2026] Bradner, S., "The Internet Standards Process -- Revision 3", BCP 9, RFC 2026, October 1996. [SHAPER] "A Rate Adaptive Shaper for Differentiated Services", RFC 2963, October 2000. 17 Full Copyright Copyright c The Internet Society (2002). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of developing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English. [Page 92] DiffServ QoS Policy Information Base March 2002 The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns. This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Table of Contents 1. Glossary..........................................................2 2. Introduction......................................................2 3. Relationship to the Diffserv Informal Management Model............2 3.1. PIB Overview....................................................3 4. Structure of the PIB..............................................5 4.1. General Conventions.............................................5 4.2. DiffServ Data Paths.............................................5 4.2.1. Data Path PRC.................................................5 4.3. Classifiers.....................................................6 4.3.1. Classifier PRC................................................7 4.3.2. Classifier Element PRC.......................................7 4.4. Meters..........................................................8 4.4.1. Meter PRC.....................................................8 4.4.2. Token-Bucket Parameter PRC....................................8 4.5. Actions.........................................................8 4.5.1. DSCP Mark Action PRC..........................................9 4.6. Queueing Elements...............................................9 4.6.1. Algorithmic Dropper PRC.......................................9 4.6.2. Random Dropper PRC...........................................10 4.6.3. Queues and Schedulers........................................12 4.7. Specifying Device Capabilities.................................14 5. PIB Usage Example................................................15 5.1. Data Path Example..............................................15 5.2. Classifier and Classifier Element Example......................15 5.3. Meter Example..................................................17 5.4. Action Example.................................................18 5.5. Dropper Examples...............................................19 5.5.1. Tail Dropper Example.........................................19 5.5.2. Single Queue Random Dropper Example..........................19 5.5.3. Multiple Queue Random Dropper Example........................20 5.6. Queue and Scheduler Example....................................22 6. Summary of the DiffServ PIB......................................24 7. PIB Operational Overview.........................................25 8. PIB Definitions..................................................26 [Page 93] DiffServ QoS Policy Information Base March 2002 8.1. The DiffServ Base PIB..........................................26 9. Acknowledgments.................................................88 10. Subject Category Considerations.................................88 11. Security Considerations.........................................88 12. Intellectual Property Considerations............................88 13. RFC Editor Considerations.......................................88 14. IANA Considerations.............................................89 15. Authors' Addresses..............................................89 16. References......................................................90 17 Full Copyright....................................................92 [Page 94]