Network Working Group M. Fine Internet Draft K. McCloghrie Expires September 2001 Cisco Systems J. Seligson K. Chan Nortel Networks S. Hahn C. Bell Intel A. Smith Allegro Networks Francis Reichmeyer PFN March 2, 2001 Differentiated Services Quality of Service Policy Information Base draft-ietf-diffserv-pib-03.txt 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.'' DiffServ QoS Policy Information Base February 2001 To view the current status of any Internet-Draft, please check the ``1id-abstracts.txt'' listing contained in an Internet-Drafts Shadow Directory, see http://www.ietf.org/shadow.html. [Page 2] DiffServ QoS Policy Information Base February 2001 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 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. Furthemore, 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 modelled. It describes the configuration and management of a Diffserv interface in terms of a Transmission Control Block (TCB) which contains, by definition, zero or more classifiers, meters, actions, algorithmic droppers, queues and schedulers. These elements are arranged according [Page 3] DiffServ QoS Policy Information Base February 2001 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 modelled 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 instructmentation of a device to support the functionalities of DiffServ, but it is useful for conceptual reasons. By not using the TCB concept, this PIB allow 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. [Page 4] DiffServ QoS Policy Information Base February 2001 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. 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: o Classify each packet according to some set of rules o Determine whether the data stream the packet is part of is within or outside its rate o Perform a set of resulting actions such as application of an appropriate drop policy and marking of the traffic with a Differentiated Services Code Point (DSCP) as defined in [DSFIELD]. o 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 descibes 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 Absolute Drop, Mark and Count actions. The "multiplexer" and "null" actions described in [MODEL] are accomplished implicitly by means of the Prid structures [Page 5] DiffServ QoS Policy Information Base February 2001 of the other elements. Queue, Scheduler and Algorithmic Dropper Tables A general extensible framework for parameterizing queuing and scheduler systems. The queue measurement dependent algorithmic droppers are also described 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 PRC's use the Prid TC (defined in [SPPI]) to indicate indirection. A Prid is a 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 Prid's to specify parameter PRC's allows the same funtional 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, [Page 6] DiffServ QoS Policy Information Base February 2001 e.g. the interface 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 specifies the interface type, 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. 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 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 [Page 7] DiffServ QoS Policy Information Base February 2001 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 order 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. 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 with the same [Page 8] DiffServ QoS Policy Information Base February 2001 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. 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. 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 modelling 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. The specific meter table may be, but does not need to be, defined in this PIB module. [Page 9] DiffServ QoS Policy Information Base February 2001 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 this or another PIB when necessary. 4.5. Actions Actions include "no action", "mark the traffic with a DSCP" or "drop the traffic". Other tasks such as "shape the traffic" or "drop based on some algorithm" are handled elsewhere as queueing mechanisms, rather than actions, consistent with [MODEL]. 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 future revisions of this PIB, or in other PIBs and also allows for the use of proprietary Actions without impact on those defined here. There is one action - the absolute drop action - that does not require additional parameters. This action silently discards all traffic presented to it. To accommodate this action, the qosAction PRC contains an attribute, qosActionType, that indicates whether the absolute drop action is to be used or if the action is described by a specific action table. [Page 10] DiffServ QoS Policy Information Base February 2001 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. Other marking actions might be specified elsewhere - these are outside the scope of this PIB. 4.5.2. Absolute Drop Action This action just silently discards all traffic presented to it. This action has no additional parameters and so is represented only within qosActionType without its specific table. 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 Droppers have a close relationship with queuing, each 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. [Page 11] DiffServ QoS Policy Information Base February 2001 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 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. 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 [Page 12] DiffServ QoS Policy Information Base February 2001 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 weight, represented here by qosRandomDropInvWeight. The availability of qosRandomDropSamplingRate as readable is important, the information provided by Sampling Rate is essential to the configuration of [Page 13] DiffServ QoS Policy Information Base February 2001 qosRandomDropInvWeight. 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. Queue Table entries specify 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 [Page 14] DiffServ QoS Policy Information Base February 2001 Scheduler. This table serves to represent the example scheduler described in the [MODEL]: other more complex representations might be created outside of this PIB. 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 Queuing 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 qosAssuredRateAbs; 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, qosAssuredRateRel 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 qosShapingRateAbs; 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, [Page 15] DiffServ QoS Policy Information Base February 2001 qosShapingRateRel. 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 qosAssuredRateEntry. NOTE: qosSchedulerMethod uses OBJECT IDENTIFIER syntax, with the different types of scheduling methods defined as OBJECT-IDENTITY. Future scheduling methods may be defined in other MIBs. 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 frwkIfCapSetRoleComboTable 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. [Page 16] DiffServ QoS Policy Information Base February 2001 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. Shaper capabilities, such as the number of rates supported, are reported using the qosIfShaperCaps table. 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 are 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 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, with the usage of each individual attribute be 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 name, with the table entry name assumed to be their second common initial part of name. "0.0" is being used to mean zeroDotZero. And for Scheduler Method "= X" means "using the OID of qoxSchedulerX". 5.1. Model's Example As an example, when this PIB's structures are used for the hypothetical configuration in [MODEL] section 8.1, the result is shown in Figure 2, 3, and 4. The parameterization table entries' values are not specified in detail here, they can be obtained from [MODEL] section 8.1. [Page 17] DiffServ QoS Policy Information Base February 2001 +---------------------+ +------------------------> Q_EF |DataPath | | | IfCapSet="If1" | | | Roles = "A+B" | | +--------------+ | IfDirection=Ingress | +------+ | +--->|Action | | Start --------------+--->|Clfr | | | | Id=EF2 | +---------------------+ | Id=1 | | | | Next=0.0 | +------+ | | | Specific=0.0 | | | | Type=AbsDrop | | | +--------------+ | | | | | | +------------+ +--------------+ | | |ClfrElement | +-->|Meter | | | | Id=EF | | | Id=EF | | | | ClfrId=1 | | | SucceedNext -+-+ | | Order=NA | | | FailNext ----+----+ | Next ------+--+ | Specific -+ | | Specific --+-+ +-----------+--+ +------------+ | | | | | | | +--------+ | +---------+ +-->|FilterEF| +-->|TBMeterEF| +--------+ +---------+ +------------+ +--------------+ |ClfrElement | +-------------------->|AlgDrop | | Id=AF11 | | | Id=AF11 | | ClfrId=1 | | | Type=tailDrop| | Order=NA | | | Next --------+--+-> Q_AF1 | Next ------+--+ | QMeasure ----+--+ | Specific --+-+ | QThreshold | +------------+ | | Specific=0.0 | | +--------------+ | | +----------+ +->|FilterAF11| +----------+ Figure 2: Example from Model Section 8.1 part 1 [Page 18] DiffServ QoS Policy Information Base February 2001 +------------+ +--------------+ |ClfrElement | +-->|Meter | | Id=AF21 | | | Id=AF21 | | ClfrId=1 | | | SucceedNext -+----------> Q_AF2 | Order=NA | | | FailNext + | | Next ------+--+ | Specific --+ | | Specific --+-+ +----------+-+-+ +------------+ | | | | | | | | | | +----------+ | | +-----------+ +->|FilterAF21| | +->|TBMeterAF21| +----------+ | +-----------+ | -----+ | | +-----------+ +->|Action | | Id=AF21F2 | | Next -----+------> Q_AF2 | Specific -+-+ | Type=Spcf | | +-----------+ | | | +---------------+ +->|DscpMarkActAF22| +---------------+ +------------+ |ClfrElement | +-----------------------------------------> Q_BE | Id=WildCard| | | ClfrId=1 | | | Order=NA | | | Next ------+--+ +--------------+ | Specific --+------>|FilterMatchAll| +------------+ +--------------+ Figure 3: Example from Model Section 8.1 part 2 +-------------+ Q_EF--->|Q | | Id=EF +--+--------------------------+ | Next ----+ | +-----------+ | [Page 19] DiffServ QoS Policy Information Base February 2001 | SchdParam --+-->|SchdParamEF| | +-------------+ +-----------+ | | +-------------+ | +----------------+ Q_AF1-->|Q | +->|Scheduler | | Id=AF1 +--+--------------------------+ | Id=Diffserv | | Next ----+ | +------------+ | | Next=0.0 | | SchdParam --+-->|SchdParamAF1| | | Method=Priority| +-------------+ +------------+ | | SchdParam=0.0 | | +----------------+ +-------------+ | Q_AF2-->|Q | | | Id=AF2 +--+--------------------------+ | Next ----+ | +------------+ | | SchdParam --+-->|SchdParamAF2| | +-------------+ +------------+ | | +-------------+ | Q_BE--->|Q | | | Id=BE +--+--------------------------+ | Next ----+ | +-----------+ | SchdParam --+-->|SchdParamBE| +-------------+ +-----------+ Figure 4: Example from Model Section 8.1 part 3 5.2. Additional Data Path Example 5.2.1. Data Path and Classifier Example Discussion The example in Figure 5 shows a single qosDataPathTable entry feeding into a single Classifier entry, with three Classifier Element and Filter Table entry pairs belonging to this Classifier 1. Notice the three Filters used here must completely classify all the traffic presented to this data path. Another level of classification can be defined that follows the Action functional DataPath elements in Figure 5. This multi-level classification allow the construction of traffic separations and specific actions at each level, like: if (dept1) then take dept1-action { if (appl1) then take dept1-appl1-action. [Page 20] DiffServ QoS Policy Information Base February 2001 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. } Minimally, the filters for appl1, appl2, appl3 may be reused for the above setup. +---------------------+ |DataPath | | IfCapSet="If1" | | Roles="A+B" | | IfDirection=Ingress | +------+ | Start --------------+--->|Clfr | +---------------------+ | Id=1 | +------+ +------------+ +--------------+ |ClfrElement | +-->|Meter | | Id=101 | | | Id=101 | | ClfrId=1 | | | SucceedNext -+--->... | Order=NA | | | FailNext ----+--->... | Next ------+--+ | Specific -+ | | Specific --+-+ +-----------+--+ +------------+ | | | +-------+ | +--------+ +-->|Filter1| +-->|TBMeter1| +-------+ +--------+ +------------+ +--------------+ |ClfrElement | +-->|Meter | | Id=102 | | | Id=102 | [Page 21] DiffServ QoS Policy Information Base February 2001 | ClfrId=1 | | | SucceedNext -+->... | Order=NA | | | FailNext ----+->... | Next ------+--+ | Specific -+ | | Specific --+-+ +-----------+--+ +------------+ | | | +-------+ | +--------+ +-->|Filter2| +-->|TBMeter2| +-------+ +--------+ +------------+ +--------------+ |ClfrElement | +-->|Meter | | Id=103 | | | Id=103 | | ClfrId=1 | | | SucceedNext -+->... | Order=NA | | | FailNext ----+->... | Next ------+--+ | Specific -+ | | Specific --+-+ +-----------+--+ +------------+ | | | +-------+ | +--------+ +-->|Filter3| +-->|TBMeter3| +-------+ +--------+ Figure 5: Additional Data Path Example Part 1 +-------------+ +-----------------+ ---->|Q | +->|Scheduler | | Id=EF | | | Id=Diffserv | | Next -------+-----------------------+ | Next=0.0 | | SchdParam -+| | | Method=Priority | +------------++ | | SchdParam=0.0 | | | +-----------------+ +------------+ | | | | +-----------+ | +->|SchdParamEF| | +-----------+ +---------------------+ | +----------------+ +-------------+ | --->|AlgDrop | +->|Q | | | Id=AF11 | | | Id=AF1 | +-------------+ | | Type=randomDrop| | | Next -------+--->|Scheduler | | | Next ----------+-+--+ | SchdParam -+| | Id=AF | | | QMeasure ------+-+ | +------------++ | Next -------+--+ | QThreshold | | | | Method=WFQ | | Specific -+ | | +------------+ | SchdParam --+--+ [Page 22] DiffServ QoS Policy Information Base February 2001 +-----------+----+ | | +-------------+ | | | | +------------+ | +-----------+ | +->|SchdParamAF1| +----------------+ | +--------------+ | +------------+ | +->|RandomDropAF11| | | +-----------+ +--------------+ | +->|SchdParamAF| | +-----------+ +----------------+ | --->|AlgDrop | | | Id=AF12 | | | Type=randomDrop| | | Next ----------+-+--+ | QMeasure ------+-+ | QThreshold | | Specific -+ | +-----------+----+ | +-----------+ | +--------------+ +->|RandomDropAF12| +--------------+ Figure 6: Additional Data Path Example Part 2 5.2.2. Meter and Action Example Discussion A simple Meter that can be parameterized by a single TBMeter entry is shown here. For Metering types that require multiple TBMeter entries for parameterization, a second level Meter and TBMeter table entries may be used. For example, for [TRTCM], with the first level TBMeter entry used for Peak Information Token Bucket, the first level SucceedNext points to the second level Meter entry, with second level TBMeter entry used for Committed Information Token Bucket. 5.2.3. Queue and Scheduler Example Discussion Example in Figure 6 shows three classified input traffic streams, EF, AF11, and AF12, feeding into their respective queue and algorithmic droppers. After their respective dropping process, the AF traffic streams feed into the same queue, QAF1X. A Scheduler, AF, is shown in Figure 6, as the sink for AF1X queue traffic, servicing AF1X queue with scheduling parameters indicated by [Page 23] DiffServ QoS Policy Information Base February 2001 SchdParamAF1X. This scheduler is used to service traffic from AF1X, AF2X, AF3X queues using weighted fair queuing method. The AF2X and AF3X queues are not shown in Figure 6, they can be very much like AF1X queue setup. Another traffic stream, EF, is handled by the EF queue. Scheduler Diffserv services output of EF queue using SchdParamEF, and output of AF scheduler using SchdParamAF, with Priority Queue scheduling method. Notice all the diffserv traffic may go out on a link with traffic shaping. The traffic shaping can be parameterize using the Shaping | Scheduler in Figure 6. For shaping, the qosShapingRate attributes should be used. The Shaping Scheduler is indicated as the last diffserv functional element of this data path by using its Next pointer with value of zeroDotZero. 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 functonal 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 February 2001 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 a 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 February 2001 8. PIB Definitions 8.1. The DiffServ Base PIB DIFFSERV-PIB PIB-DEFINITIONS ::= BEGIN IMPORTS Unsigned32, Integer32, MODULE-IDENTITY, OBJECT-TYPE FROM COPS-PR-SPPI zeroDotZero FROM SNMPv2-SMI TruthValue, TEXTUAL-CONVENTION FROM SNMPv2-TC InstanceId, ReferenceId, TagId, TagReference FROM COPS-PR-SPPI RoleCombination FROM FRAMEWORK-PIB Dscp FROM DIFFSERV-DSCP-TC; IfDirection FROM DIFF-SERV-MIB; BurstSize FROM INTEGRATED-SERVICES-MIB; qosPolicyPib MODULE-IDENTITY SUBJECT-CATEGORIES { tbd -- QoS Client Type } LAST-UPDATED "200103021800Z" 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 [Page 26] DiffServ QoS Policy Information Base February 2001 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 "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." ::= { tbd } qosCapabilityClasses OBJECT IDENTIFIER ::= { qosPolicyPib 1 } qosPolicyClasses OBJECT IDENTIFIER ::= { qosPolicyPib 2 } qosPolicyParameters OBJECT IDENTIFIER ::= { qosPolicyPib 3 } -- -- Interface Capabilities Group -- -- -- Interface Type Capability Tables -- -- The Interface type capability tables define capabilities that may -- be associated with an interface 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. -- [Page 27] DiffServ QoS Policy Information Base February 2001 -- Classification Capabilities -- -- -- The Base Capability Table -- qosBaseIfCapsTable OBJECT-TYPE SYNTAX SEQUENCE OF QosBaseIfCapsEntry PIB-ACCESS notify, 3 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 } 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), [Page 28] DiffServ QoS Policy Information Base February 2001 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, 2 STATUS current DESCRIPTION "This table specifies the classification capabilities of an interface type" ::= { qosCapabilityClasses 2 } qosIfClassificationCapsEntry OBJECT-TYPE SYNTAX QosIfClassificationEntry STATUS current DESCRIPTION "An instance of this class describes the classification capabilities of an interface." EXTENDS { qosBaseIfCapsEntry } UNIQUENESS { qosBaseIfCapsDirection, qosIfClassificationCapsSpec } ::= { qosIfClassificationCapsTable 1 } QosIfClassificationCapsEntry ::= SEQUENCE { qosIfClassificationCapsSpec BITS } [Page 29] DiffServ QoS Policy Information Base February 2001 qosIfClassificationCapsSpec OBJECT-TYPE SYNTAX BITS { ipSrcAddrClassification(1), -- indicates the ability to classify based on -- IP source addresses ipDstAddrClassification(2), -- indicates the ability to classify based on -- IP destination addresses ipProtoClassification(3), -- indicates the ability to classify based on -- IP protocol numbers ipDscpClassification(4) -- indicates the ability to classify based on -- IP DSCP ipL4Classification(5) -- indicates the ability to classify based on -- IP layer 4 port numbers for UDP and TCP } 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, 2 STATUS current DESCRIPTION "This table specifies the metering capabilities of an interface type" ::= { qosCapabilityClasses 3 } qosIfMeteringCapsEntry OBJECT-TYPE SYNTAX QosIfMeteringCapsEntry [Page 30] DiffServ QoS Policy Information Base February 2001 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 { meterByRemarking (1), meterByDropping (2), -- These capabilities indicate if the interface -- can remark out of profile packets or drop them, -- respectively } 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. -- [Page 31] DiffServ QoS Policy Information Base February 2001 qosIfAlgDropCapsTable OBJECT-TYPE SYNTAX SEQUENCE OF QosIfAlgDropCapsEntry PIB-ACCESS notify, 2 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 } ::= { qosIfAlgDropCapsTable 1 } QosIfAlgDropCapsEntry ::= SEQUENCE { qosIfAlgDropCapsType BITS } qosIfAlgDropCapsType OBJECT-TYPE SYNTAX BITS { tailDrop(2), headDrop(3), randomDrop(4) } 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." ::= { qosIfAlgDropCapsEntry 1 } [Page 32] DiffServ QoS Policy Information Base February 2001 -- -- Queue Capabilities -- qosIfQueueCapsTable OBJECT-TYPE SYNTAX SEQUENCE OF QosIfQueueCapsEntry PIB-ACCESS notify, 4 STATUS current DESCRIPTION "This table specifies the scheduling capabilities of an interface type" ::= { qosCapabilityClasses 5 } qosIfQueueCapsEntry OBJECT-TYPE SYNTAX QosIfSchedulerCapsEntry 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 DESCRIPTION [Page 33] DiffServ QoS Policy Information Base February 2001 "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 share amoungst 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, 3 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 { [Page 34] DiffServ QoS Policy Information Base February 2001 qosIfSchedulerCapsServiceDisc OBJECT IDENTIFIER, qosIfSchedulerCapsMaxInputs Unsigned32 } qosIfSchedulerCapsServiceDisc OBJECT-TYPE SYNTAX OBJECT IDENTIFIER STATUS current DESCRIPTION "The scheduling discipline for which the set of capabilities specified in this object apply. Obejct identifiers for several general purpose and well-known queuing disciplines are defined in this PIB. Queueing disciplines defined in another PIB may also be specified." ::= { qosIfSchedulerCapsEntry 1 } qosIfSchedulerCapsMaxInputs OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "The maximum number of queues that this interface type can support for the scheduler type indicated by qosIfSchedulerCapsServiceDisc. A value of zero means that there is no maximum." ::= { qosIfSchedulerCapsEntry 2 } -- -- Shaper Capabilities -- qosIfShaperCapsTable OBJECT-TYPE SYNTAX SEQUENCE OF QosIfShaperCapsEntry PIB-ACCESS notify, 3 STATUS current DESCRIPTION "This table specifies the shaping capabilities of an interface type" ::= { qosCapabilityClasses 7 } qosIfShaperCapsEntry OBJECT-TYPE SYNTAX QosIfShaperCapsEntry STATUS current DESCRIPTION "An instance of this class describes the shaping capabilities of an interface type." [Page 35] DiffServ QoS Policy Information Base February 2001 EXTENDS { qosBaseIfCapsEntry } UNIQUENESS { qosBaseIfCapsDirection, qosIfShaperCapsAlgorithm, qosIfShaperCapsMaxNumberOfRates } ::= { qosIfShaperCapsTable 1 } QosIfShaperCapsEntry ::= SEQUENCE { qosIfShaperCapsAlgorithm OBJECT IDENTIFIER, qosIfShaperCapsMaxNumberOfRates Unsigned32 } qosIfShaperCapsAlgorithm OBJECT-TYPE SYNTAX OBJECT IDENTIFIER STATUS current DESCRIPTION "The shaping method for which the set of capabilities specified in this object apply. Values that may be used for this attribute are TBD." ::= { qosIfShaperCapsEntry 1 } qosIfShaperCapsMaxNumberOfRates OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "The maximum number of rates shapers of the type indicated by qosIfShaperCapsAlgorithm may have for this interface type and flow direction." ::= { qosIfShaperCapsEntry 2 } -- -- Datapath Element Linkage Capabilities -- -- -- Datapath Element Cascade Depth -- qosIfElmDepthCapsTable OBJECT-TYPE SYNTAX SEQUENCE OF QosIfElmDepthCapsEntry PIB-ACCESS notify, 3 STATUS current DESCRIPTION "This table specifies the number of elements of the same [Page 36] DiffServ QoS Policy Information Base February 2001 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 datapath functional 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 OBJECT IDENTIFIER, qosIfElmDepthCapsCascadeMax Unsigned32 } qosIfElmDepthCapsPrc OBJECT-TYPE SYNTAX OBJECT IDENTIFIER STATUS current DESCRIPTION "The object identifier of a PRC that represents a datapath functional 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 [Page 37] DiffServ QoS Policy Information Base February 2001 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, 4 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 { qosIfElmLinkCapsPrc OBJECT IDENTIFIER, qosIfElmLinkCapsAttr Unsigned32, qosIfElmLinkCapsNextPrc OBJECT IDENTIFIER } [Page 38] DiffServ QoS Policy Information Base February 2001 qosIfElmLinkCapsPrc OBJECT-TYPE SYNTAX OBJECT IDENTIFIER STATUS current DESCRIPTION "The value is the OID of a PRC that represents a functional datapath element." ::= { qosIfElmLinkCapsEntry 1 } qosIfElmLinkCapsAttr OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "The value represents the attribute in the 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 OBJECT IDENTIFIER 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." ::= { qosIfElmLinkCapsEntry 3 } -- [Page 39] DiffServ QoS Policy Information Base February 2001 -- Policy Classes -- -- -- Data Path Table -- -- The Data Path Table enumerates the Differentiated Services -- 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, 6 STATUS current DESCRIPTION "The data path table defines the data paths in this device. Each data path is defined by the interface, role combination and traffic direction. The first functional datapath element to handle traffic for this data path is defined by a Prid in the entries of this table." ::= { qosPolicyClasses 1 } qosDataPathEntry OBJECT-TYPE SYNTAX QosDataPathEntry STATUS current DESCRIPTION "An entry in the data path table describes a single data path in this device." PIB-INDEX { qosDataPathPrid } UNIQUENESS { qosDataPathRoles, qosDataPathIfDirection } ::= { qosDataPathTable 1 } QosDataPathEntry ::= SEQUENCE { qosDataPathPrid InstanceId, qosDataPathIfName SnmpAdminString, [Page 40] DiffServ QoS Policy Information Base February 2001 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 frwkIfCapSetRoleComboTable [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." [Page 41] DiffServ QoS Policy Information Base February 2001 ::= { qosDataPathEntry 4 } qosDataPathStart OBJECT-TYPE SYNTAX Prid 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 to must exist prior to the installation of this datapath start element." ::= { qosDataPathEntry 5 } -- -- Classifiers -- -- -- Classifier Table -- -- 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. qosClfrTable OBJECT-TYPE SYNTAX SEQUENCE OF QosClfrEntry PIB-ACCESS install, 3 STATUS current DESCRIPTION "" REFERENCE "[MODEL] section 4.1" ::= { qosPolicyClasses 2 } [Page 42] DiffServ QoS Policy Information Base February 2001 qosClfrEntry OBJECT-TYPE SYNTAX QosClfrEntry STATUS current DESCRIPTION "An entry in the classifier table describes a single classifier. Each classifier element belong- ing to the this classifier must have its qosClfrElementClfrId attribute equal to qosClfrId." PIB-INDEX { qosClfrPrid } UNIQUENESS { qosClfrId } ::= { qosClfrTable 1 } QosClfrEntry ::= SEQUENCE { qosClfrPrid InstanceId, qosClfrId TagReference } 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 TagReference 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 [Page 43] DiffServ QoS Policy Information Base February 2001 -- 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. -- qosClfrElementTable OBJECT-TYPE SYNTAX SEQUENCE OF QosClfrElementEntry PIB-ACCESS install, 6 STATUS current DESCRIPTION "The classifier element table enumerates the rela- tionship between classification patterns and subse- quent downstream diffserv functional data path ele- ments. 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). Filter tables for other filter types may be defined elsewhere." 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, qosClfrElementOrder, qosClfrElementSpecific } ::= { qosClfrElementTable 1 } [Page 44] DiffServ QoS Policy Information Base February 2001 QosClfrElementEntry ::= SEQUENCE { qosClfrElementPrid InstanceId, qosClfrElementClfrId TagId, qosClfrElementPrecedence Unsigned32, qosClfrElementNext Prid, qosClfrElementSpecific Prid } qosClfrPrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosClfrElementEntry 1 } qosClfrElementClfrId OBJECT-TYPE SYNTAX TagId STATUS current DESCRIPTION "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 order 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 order may overlap in their filters: the classifier element with the highest order that matches is taken. On a given interface, there must be a complete clas- sifier in place at all times in the [Page 45] DiffServ QoS Policy Information Base February 2001 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 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." [Page 46] DiffServ QoS Policy Information Base February 2001 DEFVAL { zeroDotZero } ::= { qosClfrElementEntry 5 } -- -- 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 and used -- when necessary. -- -- Multiple meter elements may be logically cascaded -- using their qosMeterSucceedNext pointers if -- a multi-rate Meter is required. -- One example of this might be for an AF PHB implementation -- that uses two-rate meters. -- -- Cascading of individual meter elements in the PIB is intended -- to be functionally equivalent to determining the conformance -- level of a packet using a multi-rate meter. The sequential -- nature of the representation is merely a notational -- convenience for this PIB. -- -- For example: -- Conforming to RFC 2697, srTCM can be parameterized using -- two sets of qosMeterEntry and qosTBMeterEntry. -- With the first set parameterizing the Committed Burst Size -- token-bucket, second set parameterizing the Excess Burst Size -- token-bucket. With both set's qosTBMeterRate parameters -- being used to reflect the Committed Information Rate value. -- -- Conforming to RFC 2698, trTCM can be parameterized using -- two sets of qosMeterEntry and qosTBMeterEntry. -- With the first set parameterizing the Peak Information Rate -- and Peak Burst Size token-bucket, second set parameterizing -- the Committed Information Rate and Committed Burst Size -- token-bucket. -- -- Conforming to RFC 2859, tswTCM can be parameterized using -- two sets of qosMeterEntry and qosTBMeterEntry. -- With the first set parameterizing the Committed Target Rate, -- second set parametering the Peak Target Rate. -- With both set's qosTBMeterInterval being used to [Page 47] DiffServ QoS Policy Information Base February 2001 -- reflect the Average Interval as specified by RFC 2859. -- qosMeterTable OBJECT-TYPE SYNTAX SEQUENCE OF QosMeterEntry PIB-ACCESS install, 5 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 qosMeterSpecific." REFERENCE "[MODEL] section 5.1" ::= { qosPolicyClasses 4 } qosMeterEntry OBJECT-TYPE SYNTAX QosMeterEntry STATUS current DESCRIPTION "An entry in the meter table describing a single meter." PIB-INDEX { qosMeterPrid } UNIQUENESS { } ::= { qosMeterTable 1 } QosMeterEntry ::= SEQUENCE { qosMeterPrid InstanceId, qosMeterSucceedNext Prid, qosMeterFailNext Prid, qosMeterSpecific Prid } qosMeterPrid OBJECT-TYPE SYNTAX InstanceId STATUS current [Page 48] DiffServ QoS Policy Information Base February 2001 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 } 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 } [Page 49] DiffServ QoS Policy Information Base February 2001 ::= { 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 5 } -- -- 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. -- -- Entries of this table are used for both policing, as token -- bucket parameters, and shaping, as leaky bucket parameters. -- -- Note that an entry in the Token Bucket Parameter Table can -- be shared, pointed to, by multiple qosMeterTable -- and qosSchedulerTable entries. -- qosTBParamTable OBJECT-TYPE SYNTAX SEQUENCE OF QosTBParamEntry PIB-ACCESS install, 6 STATUS current DESCRIPTION "This table enumerates specific token-bucket meters [Page 50] DiffServ QoS Policy Information Base February 2001 that a system may use to police a stream of traffic. Such meters are modelled here as 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 meter." 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/Shaping algorithm associated with the [Page 51] DiffServ QoS Policy Information Base February 2001 Token/Leaky Bucket parameters. Standard values for generic algorithms are as follows: qosTBParamSimpleTokenBucket, qosTBParamAvgRate, qosTBParamSrTCMBlind, qosTBParamSrTCMAware, qosTBParamTrTCMBlind, qosTBParamTrTCMAware, qosTBParamTswTCM are specified in this PIB as OBJECT-IDENTITYs; 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. PIR and CIR in FRC 2698 for trTCM 3. CTR and PTR in RFC 2859 for TSWTCM 4. AverageRate used 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 used in [MODEL] section 5." ::= { qosTBParamEntry 4 } qosTBparamInterval OBJECT-TYPE SYNTAX Unsigned32 UNITS "microseconds" STATUS current [Page 52] DiffServ QoS Policy Information Base February 2001 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." ::= { qosTBParamEntry 5 } -- -- 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, 5 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 [Page 53] DiffServ QoS Policy Information Base February 2001 STATUS current DESCRIPTION "Each entry in the action table allows description of one specific action to be applied to traffic." PIB-INDEX { qosActionPrid } UNIQUENESS { } ::= { qosActionTable 1 } QosActionEntry ::= SEQUENCE { qosActionPrid InstanceId, qosActionNext Prid, qosActionSpecific Prid, qosActionType INTEGER } qosActionPrid OBJECT-TYPE SYNTAX InstanceId STATUS current 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 } [Page 54] DiffServ QoS Policy Information Base February 2001 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. This attribute is meaningful only if qosActionType is specific(2). For other action types, this attribute should be NULL. 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 } qosActionType OBJECT-TYPE SYNTAX INGEGER { specific(2), absoluteDrop(3) } STATUS current DESCRIPTION "This attribute indicates how the parameters of the action are to be specified. A value of specific(2) indicates that the action paramters are described in the instance of the PRC pointed to by qosActionSpecific. A value of absoluteDrop(3) indicates that the absolute drop action to be taken, and that no additional parameters apply to this action. For this action type, the value of qosActionSpecific should be zeroDotZero." ::= { qosActionEntry 4 } -- DSCP Mark Action Table -- [Page 55] DiffServ QoS Policy Information Base February 2001 -- Rows of this table are pointed to by qosActionSpecific -- to provide detailed parameters specific to the DSCP -- Mark action. -- qosDscpMarkActTable OBJECT-TYPE SYNTAX SEQUENCE OF QosDscpMarkActEntry PIB-ACCESS install, 3 STATUS current DESCRIPTION "This table enumerates specific DSCPs used for mark- ing 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 } INDEX { qosDscpMarkActDscp } 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 } [Page 56] DiffServ QoS Policy Information Base February 2001 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 } -- -- Algorithmic Drop Table -- qosAlgDropTable OBJECT-TYPE SYNTAX SEQUENCE OF QosAlgDropEntry PIB-ACCESS install, 7 STATUS current DESCRIPTION "The algorithmic drop table contains entries describ- ing an 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." PIB-INDEX { qosAlgDropPrid } [Page 57] DiffServ QoS Policy Information Base February 2001 UNIQUENESS { } ::= { 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) } STATUS current DESCRIPTION "The type of algorithm used by this dropper. A value of tailDrop(2) or headDrop(3) 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 [Page 58] DiffServ QoS Policy Information Base February 2001 queue, pointed to by qosAlgDropQMeasure, at which all newly arriving packets will be dropped. 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." ::= { 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 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 } ::= { qosAlgDropEntry 3 } qosAlgDropQMeasure OBJECT-TYPE SYNTAX Prid [Page 59] DiffServ QoS Policy Information Base February 2001 STATUS current DESCRIPTION "Points to an entry in the qosQTable to indicate the queue that a drop algorithm is to monitor when deciding whether to drop a packet. 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. 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- Drop(4) must have this point to an entry in qosRandomDropTable. For all other algorithms, this should take the value [Page 60] DiffServ QoS Policy Information Base February 2001 zeroDotzero." ::= { qosAlgDropEntry 6 } -- -- Random Drop Table -- qosRandomDropTable OBJECT-TYPE SYNTAX SEQUENCE OF QosRandomDropEntry PIB-ACCESS install, 9 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 10 } 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, qosRandomDropInvWeight, qosRandomDropSamplingRate ::= { qosRandomDropTable 1 } QosRandomDropEntry ::= SEQUENCE { qosRandomDropPrid InstanceId, qosRandomDropMinThreshBytes Unsigned32, qosRandomDropMinThreshPkts Unsigned32, qosRandomDropMaxThreshBytes Unsigned32, qosRandomDropMaxThreshPkts Unsigned32, [Page 61] DiffServ QoS Policy Information Base February 2001 qosRandomDropProbMax Unsigned32, qosRandomDropInvWeight 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 or marked. Note that this differs from the physical queue limit, which is stored in qosAlgDropQThreshold." ::= { qosRandomDropEntry 4 } [Page 62] DiffServ QoS Policy Information Base February 2001 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 } qosRandomDropInvWeight OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "The weighting of past history in affecting the calculation of the current queue average. The moving average of the queue depth uses the inverse of this value as the factor for the new queue depth, and one minus that inverse as the factor for the historical average. Implementations may choose to limit the acceptable set of values to a specified set, such as powers of 2." ::= { qosRandomDropEntry 7 } qosRandomDropSamplingRate OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION [Page 63] DiffServ QoS Policy Information Base February 2001 "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 } -- -- 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, -- qosQWeight. | -- -- Notice one or more upstream diffserv 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, 5 STATUS current DESCRIPTION "The Queue Table enumerates the individual queues on an interface." ::= { qosPolicyClasses 11 } qosQEntry OBJECT-TYPE SYNTAX QosQEntry STATUS current DESCRIPTION "An entry in the Queue Table describes a single queue [Page 64] DiffServ QoS Policy Information Base February 2001 in one direction on an interface." PIB-INDEX { qosQPrid } UNIQUENESS { } ::= { qosQTable 1 } QosQEntry ::= SEQUENCE { qosQPrid InstanceId, qosQNext Prid, qosQWeight Prid, qosQShaper Prid } 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 functional datapath element to handle traffic for this data path. This value must point to a valid (pre-existing) instance of one of: qosSchedulerEntry" ::= { qosQEntry 2 } qosQWeight OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "This Prid indicates the entry in qosAssuredRateTable the scheduler, pointed to by qosQNext, should use to service this queue. If this value is zeroDotZero, then qosQShaper must not be zeroDotZero. If this value is not zeroDotZero then the instance pointed to must exist prior to installing this entry." [Page 65] DiffServ QoS Policy Information Base February 2001 ::= { qosQEntry 3 } qosQShaper OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "This Prid indicates the entry in qosShapingRateTable the scheduler, pointed to by qosQNext, should use to service this queue. If this value is zeroDotZero, then qosQWeight must not be zeroDotZero. If this value is not zeroDotZero then the instance pointed to must exist prior to installing this entry." ::= { qosQEntry 4 } -- -- 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. -- Notice the servicing parameters the scheduler uses is -- specified by each of its upstream functional data path elements, -- most likely queues or schedulers. -- 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 qosSchedulerShaper attribute is 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, 6 STATUS current DESCRIPTION [Page 66] DiffServ QoS Policy Information Base February 2001 "The Scheduler Table enumerates packet schedulers. Multiple scheduling algorithms can be used on a given interface, with each algorithm described by one qosSchedulerEntry." REFERENCE "[MODEL] section 7.1.2" ::= { qosPolicyClasses 12 } 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 { } ::= { qosSchedulerTable 1 } QosSchedulerEntry ::= SEQUENCE { qosSchedulerPrid InstanceId, qosSchedulerNext Prid, qosSchedulerMethod OBJECT IDENTIFIER, qosSchedulerWeight Prid, qosSchedulerShaper Prid } qosSchedulerPrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosSchedulerEntry 1 } qosSchedulerSucceedNext OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "This selects the next diffserv functional datapath element to handle traffic for this data path. [Page 67] DiffServ QoS Policy Information Base February 2001 A value of zeroDotZero in this attribute indicates 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 (as indicated by [MODEL] section 7.1.4), or qosClfrEntry qosMeterEntry qosActionEntry qosAlgDropEntry (for building multiple TCB's for the same data path). This can point to another qosSchedulerEntry for implementation of multiple scheduler methods for the same datapath, and for implementation of hierarchical schedulers." DEFVAL { zeroDotZero } ::= { qosSchedulerEntry 2 } qosSchedulerMethod OBJECT-TYPE SYNTAX OBJECT IDENTIFIER STATUS current DESCRIPTION "The scheduling algorithm used by this Scheduler. Standard values for generic algorithms: qosSchedulerPriority, qosSchedulerWRR, and qosSchedulerWFQ are specified in this PIB; additional values may be further specified in other PIBs." REFERENCE "[MODEL] section 7.1.2" ::= { qosSchedulerEntry 3 } qosSchedulerWeight OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "This Prid indicates the entry in qosAssuredRateTable which indicates the priority or minimum output rate from this [Page 68] DiffServ QoS Policy Information Base February 2001 scheduler. This attribute is only used when there is more than one level of scheduler. It should have the value of zeroDotZero when not used." DEFVAL { zeroDotZero } ::= { qosSchedulerEntry 4 } qosSchedulerShaper OBJECT-TYPE SYNTAX Prid STATUS current DESCRIPTION "This Prid indicates the entry in qosShapingRateTable which indicates the maximum output rate from this scheduler. This attribute is only used when there is more than one level of scheduler. It should have the value of zeroDotZero when not used." DEFVAL { zeroDotZero } ::= { qosSchedulerEntry 5 } -- -- Assured Rate Parameters Table -- -- This is used to specify parameters for the inputs to a -- work-conserving scheduler. -- -- The scheduling parameters are separate from the Queue Entries -- for reusability and for usage by both queues and schedulers, -- and this follows the separation of data path elements from -- parameterization approach used through out this PIB. -- Usage of scheduling parameter table entry by schedulers allow -- building of hierarchical scheduling. -- qosAssuredRateTable OBJECT-TYPE SYNTAX SEQUENCE OF QosAssuredRateEntry PIB-ACCESS install, 5 STATUS current DESCRIPTION "The Assured Rate Table enumerates individual sets of scheduling parameter that can be used/reused by Queues and Schedulers." ::= { qosPolicyClasses 13 } [Page 69] DiffServ QoS Policy Information Base February 2001 qosAssuredRateEntry OBJECT-TYPE SYNTAX QosAssuredRateEntry STATUS current DESCRIPTION "An entry in the Assured Rate Table describes a single set of scheduling parameter for use by queues and schedulers." PIB-INDEX { qosAssuredRatePrid } UNIQUENESS { qosAssuredRatePriority, qosAssuredRateAbs, qosAssuredRateRel } ::= { qosAssuredRateTable 1 } QosAssuredRateEntry ::= SEQUENCE { qosAssuredRatePrid InstanceId, qosAssuredRatePriority Unsigned32, qosAssuredRateAbs Unsigned32, qosAssuredRateRel Unsigned32 } qosAssuredRatePrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosAssuredRateEntry 1 } qosAssuredRatePriority OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "The priority of this input to the associated scheduler, relative to the scheduler's other inputs." ::= { qosAssuredRateEntry 2 } qosAssuredRateAbs OBJECT-TYPE SYNTAX Unsigned32 UNITS "kilobits per second" STATUS current DESCRIPTION [Page 70] DiffServ QoS Policy Information Base February 2001 "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 effec- tively 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 qosAssuredRateRel: changes to one will affect the value of the other. They are linked by the following equation: qosAssuredRateRel = qosAssuredRateAbs * 10000/ifSpeed or, if appropriate: qosAssuredRateRel = qosAssuredRateAbs * 10000 / ifHighSpeed" REFERENCE "ifSpeed, ifHighSpeed from [IFMIB]" ::= { qosAssuredRateEntry 3 } qosAssuredRateRel 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 1/10,000 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 qosAssuredRateAbs: changes to one will affect the value of the other. They are linked by the following equation: qosAssuredRateAbs = ifSpeed * qosAssuredRateRel/10000 or, if appropriate: qosAssuredRateAbs = ifHighSpeed * qosAssuredRateRel/10000" [Page 71] DiffServ QoS Policy Information Base February 2001 REFERENCE "ifSpeed, ifHighSpeed from [IFMIB]" ::= { qosAssuredRateEntry 4 } -- -- Shaping Rate Table -- -- This contains attributes that are used to specify -- non-work-conserving parameters to a scheduler for the purpose -- of traffic shaping. These attributes limits the servicing of -- the queue/scheduler, in affect, shaping the output of the -- queue/scheduler, as described in [MODEL] section 7.2. -- -- The scheduling parameters are separate from the Queue Entries -- for reusability and for usage by both queues and schedulers, -- and this follows the separation of data path elements from -- parameterization approach used through out this PIB. -- Usage of scheduling parameter table entry by schedulers allow -- building of hierarchical scheduling. -- qosShapingRateTable OBJECT-TYPE SYNTAX SEQUENCE OF QosShapingRateEntry PIB-ACCESS install, 6 STATUS current DESCRIPTION "The Shaping Rate Table enumerates individual sets of scheduling parameter that can be used/reused by Queues and Schedulers." ::= { qosPolicyClasses 14 } qosShapingRateEntry OBJECT-TYPE SYNTAX QosShapingRateEntry STATUS current DESCRIPTION "An entry in the Assured Rate Table describes a single set of scheduling parameter for use by queues and schedulers." PIB-INDEX { qosShapingRatePrid } UNIQUENESS { qosShapingRateLevel, qosShapingRateAbs, qosShapingRateRel, qosShapingRateThreshold } [Page 72] DiffServ QoS Policy Information Base February 2001 ::= { qosShapingRateTable 1 } QosShapingRateEntry ::= SEQUENCE { qosShapingRatePrid InstanceId, qosShapingRateLevel Unsigned32, qosShapingRateAbs Unsigned32, qosShapingRateRel Unsigned32, qosShapingRateThreshold BurstSize } qosShapingRatePrid OBJECT-TYPE SYNTAX InstanceId STATUS current DESCRIPTION "An arbitrary integer index that uniquely identifies an instance of the class." ::= { qosShapingRateEntry 1 } qosShapingRateLevel OBJECT-TYPE SYNTAX Unsigned32 STATUS current DESCRIPTION "An index that indicates which level of a multi-rate shaper is being given its parameters. By convention, increasing levels have increasing rates." ::= { qosShapingRateEntry 2 } qosShapingRateAbs 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. [Page 73] DiffServ QoS Policy Information Base February 2001 Note that this attribute's value is coupled to that of qosShapingRateRel: changes to one will affect the value of the other. They are linked by the following equation: qosShapingRateRel = qosShapingRateAbs * 10000/ifSpeed or, if appropriate: qosShapingRateRel = qosShapingRateAbs * 10000/ifHighSpeed" REFERENCE "ifSpeed, ifHighSpeed from [IFMIB]" ::= { qosShapingRateEntry 3 } qosShapingRateRel OBJECT-TYPE SYNTAX Unsigned32 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 1/10,000 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 qosShapingRateAbs: changes to one will affect the value of the other. They are linked by the following equation: qosShapingRateAbs = ifSpeed * qosShapingRateRel/10000 or, if appropriate: qosShapingRateAbs = ifHighSpeed * qosShapingRateRel/10000" REFERENCE "ifSpeed, ifHighSpeed from [IFMIB]" ::= { qosShapingRateEntry 4 } [Page 74] DiffServ QoS Policy Information Base February 2001 qosShapingRateThreshold 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 conceptual row for such a shaper, this threshold is ignored and by convention is zero." REFERENCE "RFC 2963" ::= { qosShapingRateEntry 5 } -- -- 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 [Page 75] DiffServ QoS Policy Information Base February 2001 "[MODEL] sections 5 and 7.1.2" ::= { qosTBParameters 4 } 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 5 } 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 "[MODEL] sections 5 and 7.1.2" ::= { qosTBParameters 6 } 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 7 } 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" [Page 76] DiffServ QoS Policy Information Base February 2001 ::= { qosTBParameters 8 } 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 9 } -- -- 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 qosAssuredRateEntry of the queues/schedulers feeding this scheduler are used when determining the next packet to schedule." REFERENCE "[MODEL] section 7.1.2" ::= { qosSchedulerParameters 1 } qosSchedulerWRR OBJECT-IDENTITY STATUS current DESCRIPTION "For use with qosSchedulerMethod and qosIfSchedulingCapsServiceDisc to indicate Weighted Round 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 qosAssuredRateEntry of the queues/schedulers feeding this scheduler are used when determining the next packet to schedule." REFERENCE "[MODEL] section 7.1.2" ::= { qosSchedulerParameters 2 } [Page 77] DiffServ QoS Policy Information Base February 2001 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 qosAssuredRateEntry 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 -- qosPolicyPibConformance OBJECT IDENTIFIER ::= { qosPolicyPib 3 } 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." MODULE -- this module MANDATORY-GROUPS { qosPibDataPathGroup, qosPibClfrGroup, qosPibClfrElementGroup, qosPibActionGroup, qosPibAlgDropGroup, qosPibQGroup, qosPibSchedulerGroup, qosPibAssuredRateGroup, [Page 78] DiffServ QoS Policy Information Base February 2001 qosPibShapingRateGroup } 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 qosPibRandomDropGroup DESCRIPTION "This group is mandatory for devices that implement Random Drop functions." OBJECT qosClfrId MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosClfrElementClfrId MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosClfrElementPrecedence MIN-ACCESS notify DESCRIPTION "Install support is not required." [Page 79] DiffServ QoS Policy Information Base February 2001 OBJECT qosClfrElementNext MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosClfrElementSpecific MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosMeterSucceedNext MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosMeterFailNext MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosMeterSpecific MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosTBParamType MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosTBParamRate MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosTBParamBurstSize MIN-ACCESS notify DESCRIPTION [Page 80] DiffServ QoS Policy Information Base February 2001 "Install support is not required." OBJECT qosTBParamInterval MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosActionNext MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosActionSpecific MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosAlgDropType MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosAlgDropNext MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosAlgDropQMeasure MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosAlgDropQThreshold MIN-ACCESS notify DESCRIPTION "Install support is not required." [Page 81] DiffServ QoS Policy Information Base February 2001 OBJECT qosAlgDropSpecific MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosRandomDropMinThreshBytes MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosRandomDropMinThreshPkts MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosRandomDropMaxThreshBytes MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosRandomDropMaxThreshPkts MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosRandomDropInvWeight MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosRandomDropSamplingRate MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosRandomDropProbMax MIN-ACCESS notify DESCRIPTION [Page 82] DiffServ QoS Policy Information Base February 2001 "Install support is not required." OBJECT qosQNext MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosQWeight MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosQShaper MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosSchedulerMethod MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosSchedulerWeight MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosSchedulerShaper MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosSchedulerNext MIN-ACCESS notify DESCRIPTION "Install support is not required." [Page 83] DiffServ QoS Policy Information Base February 2001 OBJECT qosAssuredRatePriority MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosAssuredRateAbs MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosAssuredRateRel MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosShapingRateAbs MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosShapingRateRel MIN-ACCESS notify DESCRIPTION "Install support is not required." OBJECT qosShapingRateThreshold MIN-ACCESS notify DESCRIPTION "Install support is not required." ::= { qosPibCompliances 1 } qosPibDataPathGroup OBJECT-GROUP OBJECTS { qosDataPathStart } STATUS current DESCRIPTION [Page 84] DiffServ QoS Policy Information Base February 2001 "The Data Path Group defines the PIB Objects that describe a data path." ::= { qosPibGroups 1 } qosPibClfrGroup OBJECT-GROUP OBJECTS { qosClfrId } STATUS current DESCRIPTION "The Classifier Group defines the PIB Objects that describe a generic classifier." ::= { qosPibGroups 2 } qosPibClfrElementGroup OBJECT-GROUP OBJECTS { qosClfrElementClfrId, qosClfrElementOrder, qosClfrElementNext, qosClfrElementSpecific } STATUS current DESCRIPTION "The Classifier Group defines the PIB Objects that describe a generic classifier." ::= { qosPibGroups 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." ::= { qosPibGroups 5 } qosPibTBParamGroup OBJECT-GROUP OBJECTS { qosTBParamType, qosTBParamRate, qosTBParamBurstSize, qosTBParamInterval } [Page 85] DiffServ QoS Policy Information Base February 2001 STATUS current DESCRIPTION "The Token-Bucket Parameter Group defines the objects used in describing a single-rate token bucket meter element." ::= { qosPibGroups 6 } qosPibActionGroup OBJECT-GROUP OBJECTS { qosActionNext, qosActionSpecific } STATUS current DESCRIPTION "The Action Group defines the objects used in describing a generic action element." ::= { qosPibGroups 7 } qosPibDscpMarkActGroup OBJECT-GROUP OBJECTS { qosDscpMarkActDscp } STATUS current DESCRIPTION "The DSCP Mark Action Group defines the objects used in describing a DSCP Marking Action element." ::= { qosPibGroups 8 } qosPibAlgDropGroup OBJECT-GROUP OBJECTS { qosAlgDropType, qosAlgDropNext, qosAlgDropQMeasure, qosAlgDropQThreshold, qosAlgDropSpecific } STATUS current DESCRIPTION "The Algorithmic Drop Group contains the objects that describe algorithmic dropper operation and configura- tion." ::= { qosPibGroups 12 } qosPibRandomDropGroup OBJECT-GROUP [Page 86] DiffServ QoS Policy Information Base February 2001 OBJECTS { qosRandomDropMinThreshBytes, qosRandomDropMinThreshPkts, qosRandomDropMaxThreshBytes, qosRandomDropMaxThreshPkts, qosRandomDropProbMax, qosRandomDropInvWeight, qosRandomDropSamplingRate } STATUS current DESCRIPTION "The Random Drop Group augments the Algorithmic Drop Group for random dropper operation and configuration." ::= { qosPibGroups 13 } qosPibQGroup OBJECT-GROUP OBJECTS { qosQNext, qosQWeight, qosQShaper } STATUS current DESCRIPTION "The Queue Group contains the objects that describe an interface's queues." ::= { qosPibGroups 14 } qosPibSchedulerGroup OBJECT-GROUP OBJECTS { qosSchedulerMethod, qosSchedulerWeight, qosSchedulerShaper, qosSchedulerNext } STATUS current DESCRIPTION "The Scheduler Group contains the objects that describe packet schedulers on interfaces." ::= { qosPibGroups 15 } qosPibAssuredRateGroup OBJECT-GROUP OBJECTS { qosAssuredRatePriority, qosAssuredRateAbs, qosAssuredRateRel } STATUS current [Page 87] DiffServ QoS Policy Information Base February 2001 DESCRIPTION "The Assured Rate Group contains the objects that describe packet schedulers' parameters on inter- faces." ::= { qosPibGroups 16 } qosPibShapingRateGroup OBJECT-GROUP OBJECTS { qosShapingRateAbs, qosShapingRateRel, qosShapingRateThreshold } STATUS current DESCRIPTION "The Shaping Rate Group contains the objects that describe packet schedulers' parameters on inter- faces." ::= { qosPibGroups 17 } END [Page 88] DiffServ QoS Policy Information Base February 2001 9. Subect 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. 10. 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. 11. 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. 12. 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 [Page 89] DiffServ QoS Policy Information Base February 2001 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 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 [Page 90] DiffServ QoS Policy Information Base February 2001 Francis Reichmeyer PFN, Inc. University Park at MIT 26 Landsdowne Street Cambridge, MA 02139 Phone: +1 617 494 9980 Email: franr@pfn.com 13. 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," draft-ietf-rap-cops-pr-05.txt, October 2000. [SPPI] K. McCloghrie, et.al., "Structure of Policy Provisioning Information," draft-ietf-rap-sppi-03.txt, November 2000. [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. [FR-PIB] M. Fine, K. McCloghrie, J. Seligson, K. Chan, S. Hahn, A. Smith, F. Reichmeyer "Framework Policy Information Base", Internet Draft , November 2000 [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. [Page 91] DiffServ QoS Policy Information Base February 2001 [MODEL] Y. Bernet, A. Smith, S. Blake, D. Grossman "A Conceptual Model for DiffServ Routers", draft-ietf-diffserv-model-04.txt, July 2000. [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-07.txt, February 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 "Fuid-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] 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. [Page 92] DiffServ QoS Policy Information Base February 2001 [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. [Page 93] DiffServ QoS Policy Information Base February 2001 Table of Contents 1 Glossary ........................................................ 3 2 Introduction .................................................... 3 3 Relationship to the Diffserv Informal Management Model .......... 3 3.1 PIB Overview .................................................. 4 4 Structure of the PIB ............................................ 6 4.1 General Conventions ........................................... 6 4.2 DiffServ Data Paths ........................................... 6 4.2.1 Data Path PRC ............................................... 7 4.3 Classifiers ................................................... 7 4.3.1 Classifier PRC .............................................. 8 4.3.2 Classifier Element PRC ..................................... 8 4.4 Meters ........................................................ 9 4.4.1 Meter PRC ................................................... 9 4.4.2 Token-Bucket Parameter PRC .................................. 10 4.5 Actions ....................................................... 10 4.5.1 DSCP Mark Action PRC ........................................ 11 4.5.2 Absolute Drop Action ........................................ 11 4.6 Queueing Elements ............................................. 11 4.6.1 Algorithmic Dropper PRC ..................................... 11 4.6.2 Random Dropper PRC .......................................... 12 4.6.3 Queues and Schedulers ....................................... 14 4.7 Specifying Device Capabilities ................................ 16 5 PIB Usage Example ............................................... 17 5.1 Model's Example ............................................... 17 5.2 Additional Data Path Example .................................. 20 5.2.1 Data Path and Classifier Example Discussion ................. 20 5.2.2 Meter and Action Example Discussion ......................... 23 5.2.3 Queue and Scheduler Example Discussion ...................... 23 6 Summary of the DiffServ PIB ..................................... 24 7 PIB Operational Overview ........................................ 25 8 PIB Definitions ................................................. 26 8.1 The DiffServ Base PIB ......................................... 26 9 Subect Category Considerations .................................. 89 10 Security Considerations ........................................ 89 11 Intellectual Property Considerations ........................... 89 12 Authors' Addresses ............................................. 89 13 References ..................................................... 91 [Page 94]