Internet DRAFT - draft-aboulmagd-ccamp-transport-lmp

draft-aboulmagd-ccamp-transport-lmp




Network Working Group                                  Osama Aboul-Magd 
                                                              Don Fedyk 
Internet Draft                                          Nortel Networks 
Document: draft-aboulmagd-ccamp-transport-lmp-02.txt                      
Category: Informational                                Deborah Brungard 
                                                                   AT&T 
                                                                        
                                                          Jonathan Lang 
                                                            Sonos, Inc. 
                                                                        
                                                  Dimitri Papadimitriou 
                                                                Alcatel 
                                                                        
                                                              July 2004 
                                                                        
 
 
                    A Transport Network View of LMP 
               <draft-aboulmagd-ccamp-transport-lmp-02.txt> 
 
 
Status of this Memo 
 
    
   This document is an Internet-Draft and is in full conformance with 
   all provisions of Section 10 of RFC2026 [RFC2026].  
    
   By submitting this Internet-Draft, I certify that any applicable 
   patent or other IPR claims of which I am aware have been disclosed, 
   and any of which I become aware will be disclosed, in accordance 
   with RFC3668 [RFC3668].  
    
   Internet-Drafts are working documents of the Internet Engineering 
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   http://www.ietf.org/ietf/1id-abstracts.txt  
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1. Abstract 
    
   The Link Management Protocol (LMP) has been developed as part of the 
   Generalized MPLS (GMPLS) protocol suite to manage Traffic 
   Engineering (TE) links. The GMPLS control plane (routing and 
   signaling) uses TE links for establishing Label Switched Paths 
   (LSPs). This memo describes the relationship of the LMP procedures 
  
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   to 'discovery' as defined in the International Telecommunication 
   Union (ITU), and on-going ITU-T work. This document provides an 
   overview of LMP in the context of the ITU-T Automatically Switched 
   Optical Networks (ASON) and transport network terminology and 
   relates it to the ITU-T discovery work to promote a common 
   understanding for progressing the work of IETF and ITU-T. 
    
2. Table of Contents 
 
   1. Abstract........................................................1 
   2. Table of Contents...............................................2 
   3. Terminology.....................................................2 
   4. Introduction....................................................3 
   5. Transport Network Architecture..................................4 
   5.1 G.8080 Discovery Framework.....................................6 
   6. Discovery Technologies..........................................8 
   6.1 Generalized automatic discovery techniques G.7714..............8 
   6.2 LMP and G.8080 Terminology Mapping.............................8 
   6.2.1 TE Link Definition and Scope................................10 
   6.3 LMP and G.8080 Discovery Relationship.........................11 
   6.4 Comparing LMP and G.8080......................................12 
   7. Security Considerations........................................13 
   8. References.....................................................13 
   8.1 Normative References..........................................13 
   8.2 Informational References......................................13 
   9. Acknowledgements...............................................14 
   10. Author's Addresses............................................14 
   Full Copyright Statement..........................................16 
 
 
3. Terminology 
    
    
   The reader is assumed to be familiar with the terminology in [LMP] 
   and [LMP-TEST]. The following ITU terminology/abbreviations are used 
   in this document:  
      
   Characteristic Information:  Signal with a specific format, which is 
   transferred on "network connections". The specific formats will be 
   defined in the technology specific Recommendations. For trails the 
   Characteristic Information is the payload plus the overhead. . The 
   information transferred is characteristic of the layer network. 
    
   Link: a subset of ports at the edge of a subnetwork or access group 
   which are associated with a corresponding subset of ports at the 
   edge of another subnetwork or access group.  
    
   OTN: Optical transport network  
     
   PDH: Plesiosynchronous digital hierarchy  
     
   SDH: Synchronous digital hierarchy.  
 
  
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   Subnetwork: a set of ports which are available for the purpose of 
   routing 'characteristic information'. 
    
   Subnetwork Connection (SNC): a flexible connection that is setup and 
   released using management or control plane procedures. 
    
   Link Connection (LC): a transport entity that transfers information 
   between ports across a link. 
    
   Network Connection (NC): A concatenation of link and subnetwork 
   connections. 
    
   Connection Termination Point (CTP): A Connection Termination Point 
   (CTP) represents the state of a Connection Point (CP) [M.3100] The 
   CP is a reference point representing the end point of a link 
   connection and represents the North input port of an Adaptation 
   function.  
    
   Termination Connection Point (TCP): A reference point that 
   represents the output of a Trail Termination source function or the 
   input to a Trail Termination sink function. A network connection 
   represents a transport entity between TCPs. 
    
   Subnetwork Point (SNP): SNP is an abstraction that represents an 
   actual or potential underlying connection point (CP) or termination 
   connection point (TCP) for the purpose of control plane 
   representation.  
    
   Subnetwork Point Pool (SNPP): A set of SNP that are grouped together 
   for the purpose of routing.  
    
4. Introduction 
    
    
   The GMPLS control plane consists of several building blocks as 
   described in [GMPLS-ARCH]. The building blocks include signaling, 
   routing, and link management for establishing LSPs. For scalability 
   purposes, multiple physical resources can be combined to form a 
   single traffic engineering (TE) link for the purposes of path 
   computation and GMPLS control plane signaling.  
    
   As manual provisioning and management of these links is impractical 
   in large networks, LMP was specified to manage TE links. Two 
   mandatory management capabilities of LMP are control channel 
   management and TE link property correlation. Additional optional 
   capabilities include verifying physical connectivity and fault 
   management. [LMP] defines the messages and procedures for GMPLS TE 
   link management. [LMP-TEST] defines SONET/SDH specific messages and 
   procedures for link verification.  
     
   G.8080 Amendment 1 [G.8080] defines control plane discovery as two 
   separate processes, one process occurs within the transport plane 
   space and the other process occurs within the control plane space. 
  
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   The ITU-T has developed Recommendation G.7714 'Generalized automatic 
   discovery techniques' [G.7714] defining the functional processes and 
   information exchange related to transport plane discovery aspects: 
   i.e., layer adjacency discovery and physical media adjacency 
   discovery. Specific methods and protocols are not defined in 
   Recommendation G.7714. ITU-T Recommendation G.7714.1 'Protocol for 
   automatic discovery in SDH and OTN networks' [G.7714.1] defines a 
   protocol and procedure for transport plane layer adjacency discovery 
   (e.g. discovering the transport plane layer end point relationships 
   and verifying their connectivity). The ITU-T is currently working to 
   extend discovery to control plane aspects providing detail on a 
   Discovery framework architecture in G.8080 and a new Recommendation 
   on 'Control plane initial establishment, reconfiguration'. 
    
5. Transport Network Architecture 
    
    
   A generic functional architecture for transport networks is defined 
   in the International Telecommunications Union (ITU) recommendation 
   [G.805]. This recommendation describes the functional architecture 
   of transport networks in a technology independent way. This 
   architecture forms the basis for a set of technology specific 
   architectural recommendations for transport networks (e.g., SDH, 
   PDH, OTN, etc.) 
    
   The architecture defined in G.805 is designed using a layered model 
   with a client-server relationship between layers. The architecture 
   is recursive in nature; a network layer is both a server to the 
   client layer above it and a client to the server layer below it. 
    
   There are two basic building blocks defined in G.805: "subnetworks" 
   and "links". A subnetwork is defined as a set of ports which are 
   available for the purpose of routing "characteristic information". A 
   link consists of a subset of ports at the edge of one subnetwork (or 
   "access group") and is associated with a corresponding subset of 
   ports at the edge of another subnetwork or access group. 
    
   Two types of connections are defined in G.805: "link connection" 
   (LC) and "subnetwork connection" (SNC). A link connection is a fixed 
   and inflexible connection, while a subnetwork connection is flexible 
   and is setup and released using management or control plane 
   procedures. A network connection is defined as a concatenation of 
   subnetwork and link connections. Figure 1 illustrates link and 
   subnetwork connections. 
    
    
    
    
    
    
    
    
    
  
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                  (++++++++)              (++++++++) 
                 (   SNC    )   LC       (   SNC    ) 
                (o)--------(o)----------(o)--------(o) 
                 (          ) CP      CP (          ) 
                  (++++++++)              (++++++++) 
             
                  subnetwork              subnetwork 
    
                Figure 1: Subnetwork and Link Connections 
    
    
    
   G.805 defines a set of reference points for the purpose of 
   identification in both the management and the control plane.  These 
   identifiers are NOT required to be the same.  A link connection or a 
   subnetwork connection is delimited by connection points (CP). A 
   network connection is delimited by a termination connection point 
   (TCP). A link connection in the client layer is represented by a 
   pair of adaptation functions and a trail in the server layer 
   network. A trail represents the transfer of monitored adapted 
   characteristics information of the client layer network between 
   access points (AP). A trail is delimited by two access points, one 
   at each end of the trail. Figure 2 shows a network connection and 
   its relationship with link and subnetwork connections. Figure 2 also 
   shows the CP and TCP reference points. 
    
    
                |<-------Network Connection---------->| 
                |                                     | 
                | (++++++++)              (++++++++)  | 
                |(   SNC    )   LC       (   SNC    ) | 
                (o)--------(o)----------(o)--------(o)| 
              TCP(          )| CP    CP |(          )TCP 
                  (++++++++) |          | (++++++++) 
                             |          | 
                             |  Trail   | 
                             |<-------->| 
                             |          | 
                            ---        --- 
                            \ /        \ / 
                             -          - 
                          AP 0          0 AP 
                             |          | 
                            (oo)------(oo) 
                              
    
           
   For management plane purposes the G.805 reference points are 
   represented by a set of management objects described in ITU 
   recommendation M.3100 [M.3100]. Connection termination points (CTP) 
   and trail termination points (TTP) are the management plane objects 
   for CP and TCP respectively.  
    
  
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   In the same way as in M.3100, the transport resources in G.805 are 
   identified for the purposes of the control plane by entities 
   suitable for connection control. G.8080 introduces the reference 
   architecture for the control plane of the automatic switched optical 
   networks (ASON). G.8080 introduces a set of reference points 
   relevant to the ASON control plane and their relationship to the 
   corresponding points in the transport plane. A Subnetwork point 
   (SNP) is an abstraction that represents an actual or potential 
   underlying CP or an actual or potential TCP. A set of SNPs that are 
   grouped together for the purpose of routing is called SNP pool 
   (SNPP). Similar to LC and SNC, the SNP-SNP relationship may be 
   static and inflexible (this is referred to as an SNP link 
   connection) or it can be dynamic and flexible (this is referred to 
   as a SNP subnetwork connection). 
    
    
5.1 G.8080 Discovery Framework 
    
    
   G.8080 provides a reference control plane architecture based on the 
   descriptive use of functional components representing abstract 
   entities and abstract component interfaces. The description is 
   generic and no particular physical partitioning of functions is 
   implied. The input/output information flows associated with the 
   functional components serve for defining the functions of the 
   components and are considered to be conceptual, not physical. 
   Components can be combined in different ways and the description is 
   not intended to limit implementations. Control plane discovery is 
   described in G.8080 by using three components: Discovery Agent (DA), 
   Termination and adaptation performer (TAP), and Link Resource 
   Manager (LRM).  
    
   The objective of the discovery framework in G.8080 is to establish 
   the relationship between CP-CP link connections (transport plane) 
   and SNP-SNP link connections (control plane). The fundamental 
   characteristics of G.8080 discovery framework is the functional 
   separation between the control and the transport plane discovery 
   processes and name spaces. The separation between the two processes 
   and corresponding two name spaces has the advantage that the 
   discovery of the transport plane can be performed independent from 
   that of the control plane (and vice-versa), and independent of the 
   method used in each name space. This allows assigning link 
   connections in the control plane without the link connection being 
   physically connected.  
      
   Discovery encompasses two separate processes: (1) transport plane 
   discovery, i.e. CP-to-CP and TCP-to-TCP connectivity and (2) control 
   plane discovery, i.e. SNP-to-SNP and SNPP links. 
    
   G.8080 Amendment 1 defines the discovery agent (DA) as the entity 
   responsible for discovery in the transport plane. The DA operates in 
   the transport name space only and in cooperation with the 
   Termination and Adaptation performer [TAP], provides the separation 
  
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   between that space and the control plane names. A local DA is only 
   aware of the CPs and TCPs that are assigned to it. The DA holds the 
   CP-CP link connection in the transport plane to enable SNP-SNP link 
   connections to be bound to them at a later time by the TAP. The CP-
   CP relationship may be discovered (e.g. per G.7714.1) or provided by 
   a management system.  
    
   Control plane discovery takes place entirely within the control 
   plane name space (SNPs). The Link Resource Manager (LRM) holds the 
   SNP-SNP binding information necessary for the control plane name of 
   the link connection, while the termination adaptation performer 
   (TAP) holds the relation between the control plane name (SNP) and 
   the transport plane name (CP) of the resource. Figure 3 shows the 
   relationship and the different entities for transport and control 
   discoveries. 
    
          LRM                             LRM 
        +-----+ holds SNP-SNP Relation  +-----+ 
        |     |-------------------------|     | 
        +-----+                         +-----+ 
           |                               | 
           v                               v 
        +-----+                         +-----+ 
        |  o  | SNP's in SNPP           |  o  | 
        |     |                         |     | 
        |  o  |                         |  o  | 
        |     |                         |     | 
        |  o  |                         |  o  | 
        +-----+                         +-----+ 
           |                               | 
           v                               v        Control Plane 
        +-----+                         +-----+        Discovery 
        |     | Termination and         |     |      
     ---|-----|-------------------------|-----|--------- 
        |     | Adaptation Performer    |     |      
        +-----+       (TAP)             +-----+     Transport Plane 
          |   \                           /  |          Discovery                     
          |    \                         /   |     
          |  +-----+                +-----+  | 
          |  | DA  |                |  DA |  | 
          |  |     |                |     |  | 
          |  +-----+                +-----+  | 
          | /                              \ | 
          V/                                \V 
          O  CP (Transport Name)             O   CP (Transport Name)            
    
      Figure 3: Discover in the Control and the Transport Planes 
    
    
    
    
    
    
  
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6. Discovery Technologies 
    
    
6.1 Generalized automatic discovery techniques G.7714 
    
   Generalized automatic discovery techniques are described in G.7714 
   to aid resource management and routing for G.8080. The term routing 
   here is described in the transport context of routing connections in 
   an optical network as opposed to the routing context typically 
   associated in packet networks.  
    
   G.7714 is concerned with two types of discovery:  
   - Layer adjacency discovery 
   - Physical media adjacency discovery 
    
   Layer adjacency discovery can be used to correlate physical 
   connections with management configured attributes. Among other 
   features this capability allows reduction in configuration and the 
   detection of miswired equipment.  
    
   Physical media adjacency discovery is a process that allows the 
   physical testing of the media for the purpose of inventory capacity 
   and verifying the port characteristics of physical media adjacent 
   networks.  
    
   G.7714 does not specify specific protocols but rather the type of 
   techniques that can be used.  G.7714.1 specifies a protocol for 
   layer adjacency with respect to SDH and OTN networks for Layer 
   adjacency Discovery. A GMPLS method for Layer Discovery using 
   elements of LMP are included in this set of procedures.  
    
   An important point about the G.7714 specification is it specifies a 
   discovery mechanism for optical networks but not necessarily how the 
   information will be used. It is intended that the Transport 
   Management plane or a Transport control plane may subsequently make 
   use of the discovered information.  
    
    
    
6.2 LMP and G.8080 Terminology Mapping 
    
   GMPLS is a set of IP-based protocols, including LMP, providing a 
   control plane for multiple data plane technologies, including 
   optical/transport networks and their resources (i.e. wavelengths, 
   timeslots, etc.) and without assuming any restriction on the control 
   plane architecture (see [GMPLS-ARCH]). Whereas, G.8080 defines a 
   control plane reference architecture for optical/ transport networks 
   and without any restriction on the control plane implementation. 
   Being developed in separate standards forums, and with different 
   scope, they use different terms and definitions. 
    
   Terminology mapping between LMP and ASON (G.805/G.8080) is an 
   important step towards the understanding of the two architectures 
  
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   and allows for potential cooperation in areas where cooperation is 
   possible. To facilitate this mapping, we differentiate between the 
   two types of data links in LMP. According to LMP, a data link may be 
   considered by each node that it terminates on as either a 'port' or 
   a 'component link'. The LMP notions of port and component link are 
   supported by the G.805/G.8080 architecture. G.8080 refers to a 
   component link as a variable adaptation function i.e. a single 
   server layer trail dynamically supporting different multiplexing 
   structures. Note that when the data plane delivers its own 
   addressing space, LMP Interface_IDs and Data Links IDs are used as 
   handles by the control plane to the actual CP Name and CP-to-CP  
   Name, respectively.  
    
   The terminology mapping is summarized in the following table: 
   +----------------+--------------------+-------------------+ 
   | ASON Terms     | GMPLS/LMP Terms    | GMPLS/LMP Terms   | 
   |                | Port               | Component Link    | 
   +----------------+--------------------+-------------------+ 
   | CP             | Interface (Port)   | Interface.        |  
   |                |                    |(Comp. link)       |  
   +----------------+--------------------+-------------------+ 
   | CP Name        | Interface ID       | Interface ID(s)   | 
   |                | no further sub-    | resources (such as| 
   |                | division for(label)| timeslots, etc.)  | 
   |                | resource allocation| on this interface | 
   |                |                    | are identified by | 
   |                |                    | set of labels     | 
   +----------------+--------------------+-------------------+ 
   | CP-to-CP       | Data Link          | Data Link         | 
   +----------------+--------------------+-------------------+ 
   | CP-to-CP Name  | Data Link ID       | Data Link ID      | 
   +----------------+--------------------+-------------------+ 
   | SNP            | TE Link (Port)     | TE Link (Comp)    | 
   |                | (single link)      | (single link)     | 
   +----------------+--------------------+-------------------+ 
   | SNP Name       | Link ID            | Link ID           | 
   +----------------+--------------------+-------------------+ 
   | SNP LC         | TE Link            | TE Link           | 
   +----------------+--------------------+-------------------+ 
   | SNP LC Name    | TE Link ID         | TE Link ID        | 
   +----------------+--------------------+-------------------+ 
   | SNPP           | TE Link (Port)     | TE Link (Comp)    | 
   +----------------+--------------------+-------------------+ 
   | SNPP Name      | Link ID            | Link ID           | 
   +----------------+--------------------+-------------------+ 
   | SNPP Link      | TE Link            | TE Link           | 
   +----------------+--------------------+-------------------+ 
   | SNPP Link Name | TE Link ID         | TE Link ID        | 
   +----------------+--------------------+-------------------+ 
    
   where: 
   - Data Link ID: <Local Interface ID; Remote Interface ID> 
   - TE Link ID: <Local Link ID; Remote Link ID> 
  
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6.2.1 TE Link Definition and Scope 
 
   In the table TE link is equated the concept of SNP, SNP LC, SNPP and 
   SNPP link. The definition of the TE link is broad in scope and is 
   useful repeating here. The original definition appears in [GMPLS-
   RTG]: 
    
   "A TE link is a logical construct that represents a way to group/map 
   the information about certain physical resources (and their 
   properties) that interconnects LSRs into the information that is 
   used by Constrained SPF for the purpose of path computation, and by 
   GMPLS signaling." 
    
   While this definition is concise it is probably worth pointing some 
   of the implications of the definition.  
    
   A TE link is not limited to a single path. TE links can be formed 
   over resources (e.g. individual OC-3c links) which take identical or 
   different physical paths between Nodes.  
    
   The TE link construct is a logical construction encompassing many 
   layers in networks [RFC 3471]. A TE link can represent either 
   unallocated potential or allocated actual resources. Further 
   allocation is represented by Bandwidth reservation and the resources 
   may be real or in the case of packets virtual to allow for over 
   booking or other form of statistical multiplexing schemes.  
    
   Since TE links may represent large number of parallel resources they 
   can be bundled for efficient summarization of resource capacity. 
   Typically bundling represents a logical TE link resource at a 
   particular Interface switching capability. Once TE link resources 
   are allocated the actual capacity may be represented as LSP 
   hierarchical (tunneled) TE link capability in another logical TE 
   link [HIER].  
    
   TE links also incorporate the notion of a Forwarding Adjacency (FA) 
   and Interface Switching capability [GMPLS-ARCH]. The FA allows 
   transport resources to be represented as TE-links.  The interface 
   switching capability specifies the type of transport capability such 
   as Packet switch Capable(PSC), Layer-2 Switch Capable (L2SC), Time-
   Division Multiplex (TDM), Lambda Switch Capable (LSC) and Fiber-
   Switch Capable (FSC)..   
    
   A typical TE link between GMPLS controlled optical nodes would 
   consist of a bundled (TE link) which itself consists  
   of a mix of point-to-point links and FAs [BUNDLE] . A TE link is 
   identified by the tuple: (Bundled link Identifier(32 bit number), 
   Component link Identifier(32 bit number) and generalized label(media 
   specific)).   
    
    
 
 
  
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6.3 LMP and G.8080 Discovery Relationship 
    
   LMP currently consists of four primary procedures, of which, the 
   first two are mandatory and the last two are optional:  
      
         1.  Control channel management  
         2.  Link property correlation  
         3.  Link verification  
         4.  Fault management  
    
      
    
      
   LMP procedures that are relevant to G.8080 control plane discovery 
   are control channel management, link property correlation and Link 
   Verification.. Key to understanding G.8080 discovery aspects in 
   relation to [LMP] is that LMP procedures are specific for an IP-
   based control plane abstraction of the transport plane. 
    
   LMP control channel management is used to establish and maintain 
   control channel connectivity between LMP adjacent nodes. In GMPLS, 
   the control channels between two adjacent nodes are not required to 
   use the same physical medium as the TE links between those nodes. 
   The control channels that are used to exchange the GMPLS control-
   plane information exist independently of the TE links they manage 
   (i.e., control channels may be in-band or out-of-band, provided the 
   associated control points terminate the LMP packets). The Link 
   Management Protocol [LMP] was designed to manage TE links, 
   independently of the physical medium capabilities of the data links. 
   This is done using a Config message exchange followed by a 
   lightweight keep-alive message exchange.  
      
     
   Link property correlation is used to aggregate multiple data links 
   into a single TE Link and to synchronize the link properties.  
    
   Link verification is used to verify the physical connectivity of the 
   data links and verify the mapping of the Interface-ID to Link-ID (CP 
   to SNP). The local-to-remote associations can be obtained using a 
   priori knowledge or using the Link verification procedure.  
    
   Fault management is primarily used to suppress alarms and to 
   localize failures. It is an optional LMP procedure, it's use will 
   depend on the specific technology's capabilities.  
     
   [LMP] supports distinct transport and control plane name spaces with 
   the (out-of-band) TRACE object (see [LMP-TEST]). The LMP TRACE 
   object allows transport plane names to be associated with interface 
   identifiers [LMP-TEST].  
     
   Aspects of LMP link verification appear similar to G.7714.1 
   discovery, however the two procedures are different. G.7714.1 
   provides discovery of the transport plane layer adjacencies. It 
  
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   provides a generic procedure to discover the connectivity of two end 
   points in the transport plane. Whereas, LMP link verification 
   procedure is a control plane driven procedure and assumes either (1) 
   a priori knowledge of the associated data plane's local and remote 
   end point connectivity and Interface_IDs (e.g. via management plane 
   or use of G.7714.1), or (2) support of the remote node for 
   associating the data interface being verified with the content of 
   the TRACE object (inferred mapping). For SONET/SDH transport 
   networks, LMP verification uses the SONET/SDH Trail Trace identifier 
   (see [G.783]).  
     
   G.7714.1 supports the use of transport plane discovery independent 
   of the platform using the capability. Furthermore G.7714.1 specifies 
   the use of a Discovery Agent could be located in an external system 
   and the need to support the use of text-oriented man-machine 
   language to provide the interface. Therefore, G.7714.1 limits the 
   discovery messages to printable characters defined by [T.50] and 
   requires Base64 encoding for the TCP-ID and DA ID. External name-
   servers may be used to resolve the G.7714.1 TCP name, allowing the 
   TCP to have an IP, NSAP or any other address format. Whereas, LMP is 
   based on the use of an IP-based control plane, and the LMP interface 
   ID uses IPv4, IPv6, or unnumbered interface IDs.  
     
    
6.4 Comparing LMP and G.8080 
    
   LMP exists to support GMPLS TE link discovery. In section 5.2.1 we 
   elaborated on the definition of the TE link. LMP enables the aspects 
   of TE links to be discovered, and delivered to the control plane, 
   more specifically the routing plane.  G.8080 and G.7714 are agnostic 
   to the type of control plane and discovery protocol used. LMP is a 
   valid realization of a control plane discovery process under a 
   G.8080 model.  
    
   G.7714 specifies transport plane discovery with respect to the 
   transport layer CTPs or TCPs using ASON conventions and naming for 
   the elements of the ASON control plane and the ASON management 
   plane. This discovery supports a centralized management model of 
   configuration as well as a distributed control plane model, in other 
   words discovered items can be reported to the management plane or 
   the control plane. G.7714.1 provides one realization of a transport 
   plane discovery process. 
    
   Today LMP and G.7714, G7714.1 are defined in different Standards 
   Organizations.  They have evolved out of different naming schemes 
   and architectural concepts.  Whereas G.7714.1 supports a transport 
   plane layer adjacency connectivity verification which can be used by 
   a control plane or a management plane, LMP is a control plane 
   procedure for managing GMPLS TEs (GMPLSĘs control plane 
   representation of the transport plane connections).  
      
    
    
  
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7. Security Considerations 
 
   Since this draft is purely descriptive in nature it does not 
   introduce any security issues. 
    
   G.8080 and G.7714/G.7714.1 provide security as associated with the 
   Data Communications Network on which they are implemented. 
    
   LMP is specified using IP which provides security mechanisms 
   associated with the IP network on which it is implemented. 
    
8. References 
    
8.1 Normative References 
    
   [RFC2026]    S.Bradner, "The Internet Standards Process -- 
                Revision3", BCP 9, RFC 2026, October 1996. 
    
   [RFC3668]    S. Bradner, "Intellectual Property Rights in IETF 
                Technology", BCP 79, RFC 3668, February 2004. 
    
    
8.2 Informational References  
    
   [LMP]       J.P.Lang (Editor), "Link Management Protocol," draft-
                ietf-ccamp-lmp-10.txt, October 2003. 
     
   [LMP-TEST]  J.P.Lang et al., "SONET/SDH Encoding for Link     
                Management Protocol (LMP) Test messages," draft-ietf-
                draft-ietf-ccamp-lmp-test-sonet-sdh-04.txt, December 
                2004. 
    
   [GMPLS-ARCH] Eric Mannie (Editor), "Generalized Multi-protocol Label 
                Switching Architecture," draft-ietf-ccamp-gmpls-
                architecture-07.txt, May 2003. 
    
   [RFC 3471]  Lou Berger (Editor), "Generalized Multi-Protocol Label 
                Switching (GMPLS)Signaling Functional Description," 
                draft-ietf-ccamp-gmpls-architecture-07.txt, May 2003. 
    
   [GMPLS-RTG] K. Kompella & Y. Rekhter (editors) "Routing Extensions 
                in Support of Generalized Multi-Protocol Label 
                Switching", draft-ietf-ccamp-gmpls-routing-09.txt, 
                December 2003. 
    
   [HIER] K. Kompella & Y. Rekhter " LSP Hierarchy with Generalized 
                MPLS TE", draft-ietf-mpls-lsp-hierarchy-08.txt, 
                September 2002 
    
   [BUNDLE] K. Kompella, Y. Rekhter, Lou Berger "Link Bundling in MPLS 
                Traffic Engineering", draft-ietf-mpls-bundle-04.txt, 
                July 2002 
    
  
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                 Draft-aboulmagd-transport-lmp-02.txt        July 2004 
 
 
    
   "For information on the availability of ITU Documents, please see 
   http://www.itu.int" 
    
    
   [G.783]     ITU-T G.783 (2004), Characteristics of synchronous 
                digital hierarchy (SDH) equipment functional blocks. 
    
   [G.805]     ITU-T G.805 (2000), Generic functional architecture of 
                transport networks. 
    
   [G.7714]    ITU-T G.7714/Y.1705 (2001), Generalized automatic 
                discovery techniques. 
    
   [G.7714.1]  ITU-T G.7714.1/Y.1705.1 (2003), Protocol for automatic 
                discovery in SDH and OTN networks. 
    
   [G.8080]    ITU-T G.8080/Y.1304 (2001), Architecture for the 
                automatically switched optical network (ASON). 
    
   [M.3100]    ITU-T M.3100 (1995), Generic Network Information Model 
    
    
   [T.50]      ITU-T T.50 (1992), International Reference Alphabet 
    
9. Acknowledgements 
    
   The authors would like to thank Astrid Lozano, John Drake, Adrian 
   Farrel and Stephen Shew for their valuable comments. 
    
10. Author's Addresses 
    
   Osama Aboul-Magd 
   Nortel Networks 
   P.O. Box 3511, Station 'C' 
   Ottawa, Ontario, Canada 
   K1Y-4H7 
   Phone: +1 613 763-5827 
   Email: osama@nortelnetworks.com 
    
   Don Fedyk 
   Nortel Networks 
   600 Technology Park Drive 
   Billerica, MA, 01821 
   Email: dwfedyk@nortelnetworks.com 
    
   Deborah Brungard  
   AT&T 
   Rm. D1-3C22 
   200 S. Laurel Ave. 
   Middletown, NJ 07748, USA 
   Email: dbrungard@att.com 
    
  
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   Jonathan P. Lang  
   Sonos, Inc. 
   506 Chapala Street 
   Santa Barbara, CA 93101 
   Email : jplang@ieee.org 
    
   Dimitri Papadimitriou 
   Alcatel 
   Francis Wellesplein, 1 
   B-2018 Antwerpen, Belgium 
   Phone: +32 3 240-84-91 
   Email: dimitri.papadimitriou@alcatel.be 
    








































  
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