--- 1/draft-ietf-mpls-tp-identifiers-00.txt 2010-03-09 01:11:03.000000000 +0100 +++ 2/draft-ietf-mpls-tp-identifiers-01.txt 2010-03-09 01:11:03.000000000 +0100 @@ -1,19 +1,19 @@ MPLS Working Group M. Bocci Internet-Draft Alcatel-Lucent Intended status: Standards Track G. Swallow -Expires: May 14, 2010 Cisco - November 10, 2009 +Expires: September 9, 2010 Cisco + March 8, 2010 MPLS-TP Identifiers - draft-ietf-mpls-tp-identifiers-00 + draft-ietf-mpls-tp-identifiers-01 Abstract This document specifies identifiers for MPLS-TP objects. Included are identifiers conformant to existing ITU conventions and identifiers which are compatible with existing IP, MPLS, GMPLS, and Pseudowire definitions. Status of this Memo @@ -29,25 +29,25 @@ and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. - This Internet-Draft will expire on May 14, 2010. + This Internet-Draft will expire on September 9, 2010. Copyright Notice - Copyright (c) 2009 IETF Trust and the persons identified as the + Copyright (c) 2010 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as @@ -67,52 +67,45 @@ 5.2. MPLS-TP LSP Identifiers . . . . . . . . . . . . . . . . . 7 5.3. Mapping to GMPLS Signalling . . . . . . . . . . . . . . . 8 6. Pseudowire Path Identifiers . . . . . . . . . . . . . . . . . 8 7. Maintenance Identifiers . . . . . . . . . . . . . . . . . . . 9 7.1. Maintenance Entity Group Identifiers . . . . . . . . . . . 9 7.1.1. ICC based MEG_IDs . . . . . . . . . . . . . . . . . . 9 7.1.2. IP Compatible MEG_IDs . . . . . . . . . . . . . . . . 10 7.1.2.1. MPLS-TP Tunnel MEG_IDs . . . . . . . . . . . . . . 10 7.1.2.2. MPLS-TP LSP MEG_IDs . . . . . . . . . . . . . . . 10 7.1.2.3. Pseudowire MEG_IDs . . . . . . . . . . . . . . . . 10 - 7.2. Maintenance Points . . . . . . . . . . . . . . . . . . . . 11 - 7.2.1. Maintenance Point_IDs for MPLS-TP LSPs and Tunnels . . 11 - 7.2.1.1. MPLS-TP Tunnel_MEP_ID . . . . . . . . . . . . . . 11 - 7.2.1.2. MPLS-TP LSP_MEP_ID . . . . . . . . . . . . . . . . 11 - 7.2.1.3. MPLS-TP LSP_MIP_ID . . . . . . . . . . . . . . . . 11 - 7.2.2. Maintenance Identifiers for Pseudowires . . . . . . . 12 - 7.2.2.1. MEP_IDs for PW T-PEs . . . . . . . . . . . . . . . 12 - 7.2.2.2. MP_IDs for Pseudowires . . . . . . . . . . . . . . 12 + 7.2. MEP_IDs . . . . . . . . . . . . . . . . . . . . . . . . . 11 + 7.2.1. ICC based MEP_IDs . . . . . . . . . . . . . . . . . . 11 + 7.2.2. IP based MEP_IDs . . . . . . . . . . . . . . . . . . . 11 + 7.2.2.1. MEP_IDs for MPLS-TP LSPs and Tunnels . . . . . . . 11 + 7.2.2.2. MEP_IDs for Pseudowires . . . . . . . . . . . . . 12 + 7.2.2.3. MEP_IDs for Pseudowire Segments . . . . . . . . . 12 + 7.3. MIP_IDs . . . . . . . . . . . . . . . . . . . . . . . . . 13 8. Open issues . . . . . . . . . . . . . . . . . . . . . . . . . 13 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13 9.1. Normative References . . . . . . . . . . . . . . . . . . . 13 9.2. Informative References . . . . . . . . . . . . . . . . . . 14 - Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15 + Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14 1. Introduction This document specifies identifiers to be used in within the - Transport Profile of Multiprotocol Label Switching (MPLS-TP). where - compatibility with existing MPLS control plane conventions are - necessary. The MPLS-TP requirements [13] require that the elements - and objects in an MPLS-TP environment are able to be configured and - managed without a control plane. In such an environment many - conventions for defining identifiers are possible. In particular, - identifiers conformant to existing ITU conventions are defined. It - is also anticipated that operational environments where MPLS-TP - objects, e.g. Label Switched Paths (LSPs) and Pseudowires (PWs) will - be signaled via existing protocols such as the Label Distribution - Protocol (RFC 4447) [1] and the Resource Reservation Protocol as it - is applied to Generalized Multi-protocol Label Switching (RFCs 3471 & - 3473) [2][3] (GMPLS). This document defines a set of identifiers for - MPLS-TP which are both compatible with those protocols and applicable - to MPLS-TP management and OAM functions. + Transport Profile of Multiprotocol Label Switching (MPLS-TP). The + MPLS-TP requirements [12] require that the elements and objects in an + MPLS-TP environment are able to be configured and managed without a + control plane. In such an environment many conventions for defining + identifiers are possible. This document defines identifiers for + MPLS-TP management and OAM functions suitable to ITU conventions and + to IP/MPLS conventions. Applicability of the different identifier + schemas to different applications are outside the scope of this + document. 1.1. Terminology AII: Attachment Interface Identifier ASN: Autonomous System Number FEC: Forwarding Equivalence Class GMPLS: Generalized Multi-Protocol Label Switching @@ -120,35 +113,35 @@ ICC: ITU Carrier Code LSP: Label Switched Path LSR: Label Switching Router ME: Maintenance Entity MEG: Maintenance Entity Group - MEP: Maintenance End Point + MEP: Maintenance Entity Group End Point - MIP: Maintenance Intermediate Point + MIP: Maintenance Entity Group Intermediate Point MPLS: Multi-Protocol Label Switching OAM: Operations, Administration and Maintenance P2MP: Point to Multi-Point + P2P: Point to Point PSC: Protection State Coordination PW: Pseudowire - RSVP: Resource Reservation Protocol RSVP-TE: RSVP Traffic Engineering S-PE: Switching Provider Edge T-PE: Terminating Provider Edge Requirements Language @@ -147,21 +140,21 @@ RSVP-TE: RSVP Traffic Engineering S-PE: Switching Provider Edge T-PE: Terminating Provider Edge Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this - document are to be interpreted as described in RFC 2119 [4]. + document are to be interpreted as described in RFC 2119 [1]. 2. Named Entities In order to configure, operate and manage a transport network based on the MPLS Transport Profile, a number of entities require identification. Identifiers for the follow entities are defined in this document: o Operator @@ -175,38 +168,39 @@ o PW o Interface o MEG o MEP o MIP + o Tunnel Note that we have borrowed the term tunnel from RSVP-TE (RFC 3209) - [5] where it is used to describe an entity that provides an LSP + [2] where it is used to describe an entity that provides an LSP connection between a source and destination LSR which in turn is instantiated by one or more LSPs, where the additional LSPs are used for protection or re-grooming of the tunnel. 3. Uniquely Identifying an Operator Two forms of identification are defined, one that is compatible with IP operational practice called a Global_ID and one compatible with ITU practice, the ICC. An Operator MAY be identified either by its Global_ID or by its ICC. 3.1. The Global ID - RFC 5003 [6] defines a globally unique Attachment Interface + RFC 5003 [3] defines a globally unique Attachment Interface Identifier (AII). That AII is composed of three parts, a Global ID which uniquely identifies a operator, a prefix, and finally and attachment circuit identifier. We have chosen to use that Global ID for MPLS-TP. Quoting from RFC 5003, section 3.2, "The global ID can contain the 2-octet or 4-octet value of the operator's Autonomous System Number (ASN). It is expected that the global ID will be derived from the globally unique ASN of the autonomous system hosting the PEs containing the actual AIIs. The presence of a global ID based on the operator's ASN ensures that the AII will be globally unique." @@ -245,36 +239,36 @@ In existing MPLS deployments Node_IDs are IPv4 addresses. Therefore we have chosen the Node_ID to be a 32-bit value assigned by the operator. Where IPv4 addresses are in use the Node_ID can be automatically mapped to the LSR's /32 IPv4 loopback address. Note that, when IP reachability is not needed, the 32-bit Node_ID is not required to have any association with the IPv4 address space used in the operator's IGP or BGP, other that that they be uniquely chosen within the scope of that operator. - GMPLS signaling [2] requires interface identification. We have + GMPLS signaling [4] requires interface identification. We have chosen to adopt the conventions of that RFC. GMPLS allows three formats for the Interface_ID. For IP numbered links, it is simply the IPv4 or IPv6 address associated with the interface. The third format consists of an IPv4 Address plus a 32-bit unsigned integer for the specific interface. For MPLS-TP, we have adopted a format consistent with the third format above. In MPLS-TP, each interface is assigned a 32-bit identifier which we call a Logical Interface Handle (LIH). The LIH MUST be unique within the context of the Node_ID. We map the Node_ID to the field the field which carries the IP address. That is, an IF_ID is a 64-bit identifier consisting of the Node_ID followed by the LIH. The LIH in turn is a 32-bit unsigned integer unique to the - node. The LIH value 0 has special meaning (see section - Section 7.2.1.3 and must not be used as the LIH in an MPLS-TP IF_ID. + node. The LIH value 0 has special meaning (see section Section 7.3 + and must not be used as the LIH in an MPLS-TP IF_ID. In situations where a Node_ID or an IF_ID needs to be globally unique, this is accomplished by prefixing the identifier with the operator's Global_ID. The combination of Global_ID::Node_ID we call an Global Node ID or Global_Node_ID. Likewise, the combination of Global_ID::Node_ID::LIH we call an Global Interface ID or Global_IF_ID. MPLS-TP Tunnels (see section Section 5.1) also need interface identifiers. A procedure for automatically generating these is @@ -328,43 +322,43 @@ Src-Global_ID::Src-Node_ID::Src-Tunnel_Num:: Dst-Global_ID::Dst- Node_ID::Dst-Tunnel_Num::LSP_Num 5.3. Mapping to GMPLS Signalling This section defines the mapping from an MPLS-TP LSP_ID to GMPLS. At this time, GMPLS has yet to be extended to accommodate Global_IDs. Thus a mapping is only made for the network unique form of the LSP_ID. - GMPLS signaling [3] uses a 5-tuple to uniquely identify an LSP within + GMPLS signaling [5] uses a 5-tuple to uniquely identify an LSP within a operator's network. This tuple is composed of a Tunnel Endpoint Address, Tunnel_ID, Extended Tunnel ID, and Tunnel Sender Address and (GMPLS) LSP_ID. In situations where a mapping to the GMPLS 5-tuple is required, the following mapping is used. o Tunnel Endpoint Address = Dst-Node_ID o Tunnel_ID = Src-Tunnel_Num o Extended Tunnel_ID = Src-Node_ID o Tunnel Sender Address = Src-Node_ID o LSP_ID = LSP_Num 6. Pseudowire Path Identifiers - Pseudowire signaling (RFC 4447 [1]) defines two FECs used to signal + Pseudowire signaling (RFC 4447 [6]) defines two FECs used to signal pseudowires. Of these, FEC Type 129 along with AII Type 2 as defined - in RFC 5003 [6] fits the identification requirements of MPLS-TP. + in RFC 5003 [3] fits the identification requirements of MPLS-TP. In an MPLS-TP environment, a PW is identified by a set of identifiers which can be mapped directly to the elements required by FEC 129 and AII Type 2. To distinguish this identifier from other Pseudowire Identifiers, we call this a Pseudowire Path Identifier or PW_Path_Id. The AII Type 2 is composed of three fields. These are the Global_ID, the Prefix, and the AC_ID. The Global_ID used in this document is identical to the Global_ID defined in RFC 5003. The Node_ID is used as the Prefix. The AC_ID is as defined in RFC 5003. @@ -378,31 +372,37 @@ is equivalent to AGIa::AIIc::AIIb. We note that in a signaled environment, the required convention in RFC 4447 is that at a particular endpoint, the AII associated with that endpoint comes first. The complete PW_Path_Id is: AGI:Src-Global_ID::Src-Node_ID::Src-AC_ID:: Dst-Global_ID::Dst- Node_ID::Dst-AC_ID. 7. Maintenance Identifiers - [Note this section needs to reconciled with on going ITU and MPLS WG - discussions on Maintenance Points.] + [Note this section needs to reconciled with the MPLS-TP OAM + Framework] In MPLS-TP a Maintenance Entity Group (MEG) represents an Entity that requires management and defines a relationship between a set of - maintenance points. A maintenance point is either Maintenance End- - point (MEP) or a Maintenance Intermediate Point (MIP). A Maintenance - Entity is a relationship between two MEPs. This section defines a - means of uniquely identifying Maintenance Entity Groups, Maintenance - Entities and uniquely defining MEPs and MIPs within the context of a - Maintenance Entity Group. + maintenance points. A maintenance point is either Maintenance Entity + Group End-point (MEP) or a Maintenance Entity Group Intermediate + Point (MIP). Maintenance points are uniquely associated with a MEG. + Within the context of a MEG, MEPs and MIPs must be uniquely + identified. This section defines a means of uniquely identifying + Maintenance Entity Groups, Maintenance Entities and uniquely defining + MEPs and MIPs within the context of a Maintenance Entity Group. + + Note that depending on the requirements of a particular OAM + interaction, the MPLS-TP maintenance entity context may be provided + either explicitly using the MEG_IDs described above or implicitly by + the label of the received OAM message. 7.1. Maintenance Entity Group Identifiers Maintenance Entity Group Identifiers (MEG_IDs) are required for MPLS-TP Paths and Pseudowires. Two classes of MEG_IDs are defined, one that follows the IP compatible identifier defined above as well as the ICC-format. 7.1.1. ICC based MEG_IDs @@ -459,88 +459,85 @@ 7.1.2.3. Pseudowire MEG_IDs For Pseudowires a MEG pertains to a single PW. The IP compatible MEG_ID for a PW is simply the corresponding PW_Path_ID. We note that while the two identifiers are syntactically identical, they have different semantics. This semantic difference needs to be made clear. For instance if both a PW_Path_ID and a PW_MEG_ID is to be encoded in TLVs different types need to be assigned for these two identifiers. -7.2. Maintenance Points +7.2. MEP_IDs - Maintenance points are uniquely associated with a MEG. Within the - context of a MEG, MEPs and MIPs must be uniquely identified. This - section describes how MIPs and MEPs are identified. +7.2.1. ICC based MEP_IDs - Note that depending on the requirements of a particular OAM - interaction, the MPLS-TP maintenance entity context may be provided - either explicitly using the MEG_IDs described above or implicitly by - the label of the received OAM message. + ICC-based MEP_IDs for MPLS-TP LSPs and Pseudowires MAY be formed by + appending a unique number to the MEG_ID defined in section + Section 7.1.1 above. Within the context of a particular MEG, we call + the identifier associated with a MEP the MEP Index (MEP_Index). The + MEP_Index is administratively assigned and is encoded as a 16-bit + unsigned integer. An ICC-based MEP_ID is: -7.2.1. Maintenance Point_IDs for MPLS-TP LSPs and Tunnels + MEG_ID::MEP_Index + + An ICC-based MEP ID is globally unique by construction given the ICC- + based MEG_ID global uniqueness. + +7.2.2. IP based MEP_IDs + +7.2.2.1. MEP_IDs for MPLS-TP LSPs and Tunnels In order to automatically generate MEP_IDs for MPLS-TP Tunnels and LSPs, we use the elements of identification that are unique to an endpoint. This ensures that MEP_IDs are unique for all Tunnels and LSPs within a operator. When Tunnels or LSPs cross operator boundaries, these are made unique by pre-pending them with the operator's Global_ID. -7.2.1.1. MPLS-TP Tunnel_MEP_ID +7.2.2.1.1. MPLS-TP Tunnel_MEP_ID A MPLS-TP Tunnel_MEP_ID is: Src-Node_ID::Src-Tunnel_Num In situations where global uniqueness is required this becomes: Src-Global_ID::Src-Node_ID::Src-Tunnel_Num -7.2.1.2. MPLS-TP LSP_MEP_ID +7.2.2.1.2. MPLS-TP LSP_MEP_ID A MPLS-TP LSP_MEP_ID is: Src-Node_ID::Src-Tunnel_Num::LSP_Num In situations where global uniqueness is required this becomes: Src-Global_ID::Src-Node_ID::Src-Tunnel_Num::LSP_Num -7.2.1.3. MPLS-TP LSP_MIP_ID - - At a cross connect point, in order to automatically generate MIP_IDs - for MPLS-TP LSPs, we simply use the IF_IDs of the two interfaces - which are cross connected via the label bindings of the MPLS-TP LSP. - If only one MIP is configured, then the MIP_ID is formed using the - Node_ID and an LIH of 0. - -7.2.2. Maintenance Identifiers for Pseudowires - - Like MPLS-TP LSPs, Pseudowire endpoints (T-PEs) require MEP-IDs. - Pseudowire S-PEs, however, are a special case. Here the Maintenance - Entity takes on some of the functionality of both a MIP and a MEP. - Provisionally we are calling these a Maintenance Point or MP. - -7.2.2.1. MEP_IDs for PW T-PEs +7.2.2.2. MEP_IDs for Pseudowires - In order to automatically generate MEP_IDs for PWs, we simply use the + Like MPLS-TP LSPs, Pseudowire endpoints (T-PEs) require MEP_IDs. In + order to automatically generate MEP_IDs for PWs, we simply use the AGI plus the AII associated with that end of the PW. Thus a MEP_ID - for an Pseudowire T-PE takes the form: + used in end-to-end for an Pseudowire T-PE takes the form: AGI:Src-Global_ID::Src-Node_ID::Src-AC_ID -7.2.2.2. MP_IDs for Pseudowires +7.2.2.3. MEP_IDs for Pseudowire Segments - The MP_ID is formed by a combination of a PW MEP_ID and the + In some OAM communications, messages are originated at one end of a + PW segment and relayed to the other end by setting the TTL of the PW + label to one. + + The MEP_ID Is Formed by a combination of a PW MEP_ID and the identification of the local node. At an S-PE, there are two PW - segments. We distinguish the segments by using the MEP-ID which is + segments. We distinguish the segments by using the MEP_ID which is upstream of the PW segment in question. To complete the identification we suffix this with the identification of the local node. +-------+ +-------+ +-------+ +-------+ | | | | | | | | | A|---------|B C|---------|D E|---------|F | | | | | | | | | +-------+ +-------+ +-------+ +-------+ T-PE1 S-PE2 S-PE3 T-PE4 @@ -556,116 +553,105 @@ Src-Node_ID = T-PE1 Src-AC_ID = AII1 Dst-Global_ID = GID1 Dst-Node_ID = T-PE1 Dst-AC_ID = AII4 The MEP_ID at point A would be AGI1::GID1:T-PE1::AII1. The MP_ID at point C would be AGI1::GID1:T-PE1::AII1::GID1:S-PE2. For interaction where the T-PE is acting as the segment endpoint, it - too may use the MP_ID. - -8. Open issues + too may use the Pseudowire Segment MEP_ID. - 1. We have two means of identifying operators. Should either be - allowed in all cases or can we constrain this. I.e. when there - are both IP compatible and ITU compatible IDs for an Object can - we constrain the operator ID to the corresponding format? - Clearly when only one identifier is defined the both must be - allowed. +7.3. MIP_IDs - 2. Details on MEP and MIP identifiers are subject to ongoing - discussions. Further based on some discussion in Stockholm, ITU - style identifiers for MEPs and MIPs were removed from this - version. However, consensus for this needs to be verified. + At a cross connect point, in order to automatically generate MIP_IDs + for MPLS-TP, we simply use the IF_IDs of the two interfaces which are + cross connected via the label bindings of the MPLS-TP LSP. If only + one MIP is configured, then the MIP_ID is formed using the Node_ID + and an LIH of 0. In some contexts, such as LSP Ping[13], the Node_ID + alone may be used as the MEP_ID. - 3. Pseudowire Maintenance Points need to be kept aligned with the - model for Pseudowire maintenance. +8. Open issues - 4. Identifiers for P2MP entities + 1. MEPs and MIPs need to be aligned with MPLS-TP OAM Framework. - 5. Tandem connection Identification - the identification should be - exactly the same as any other MPLS-TP LSP. However, in the ACH - TLV draft we could have a different TLV with the same format as - an MPLS-TP LSP, if there are places where the distinction becomes - important. + 2. Identifiers for P2MP entities. 9. References 9.1. Normative References - [1] Martini, L., Rosen, E., El-Aawar, N., Smith, T., and G. Heron, - "Pseudowire Setup and Maintenance Using the Label Distribution - Protocol (LDP)", RFC 4447, April 2006. - - [2] Berger, L., "Generalized Multi-Protocol Label Switching (GMPLS) - Signaling Functional Description", RFC 3471, January 2003. - - [3] Berger, L., "Generalized Multi-Protocol Label Switching (GMPLS) - Signaling Resource ReserVation Protocol-Traffic Engineering - (RSVP-TE) Extensions", RFC 3473, January 2003. - - [4] Bradner, S., "Key words for use in RFCs to Indicate Requirement + [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. - [5] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V., and + [2] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V., and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP Tunnels", RFC 3209, December 2001. - [6] Metz, C., Martini, L., Balus, F., and J. Sugimoto, "Attachment + [3] Metz, C., Martini, L., Balus, F., and J. Sugimoto, "Attachment Individual Identifier (AII) Types for Aggregation", RFC 5003, September 2007. + [4] Berger, L., "Generalized Multi-Protocol Label Switching (GMPLS) + Signaling Functional Description", RFC 3471, January 2003. + + [5] Berger, L., "Generalized Multi-Protocol Label Switching (GMPLS) + Signaling Resource ReserVation Protocol-Traffic Engineering + (RSVP-TE) Extensions", RFC 3473, January 2003. + + [6] Martini, L., Rosen, E., El-Aawar, N., Smith, T., and G. Heron, + "Pseudowire Setup and Maintenance Using the Label Distribution + Protocol (LDP)", RFC 4447, April 2006. + [7] Kompella, K., Rekhter, Y., and A. Kullberg, "Signalling Unnumbered Links in CR-LDP (Constraint-Routing Label Distribution Protocol)", RFC 3480, February 2003. [8] Kompella, K., Rekhter, Y., and L. Berger, "Link Bundling in MPLS Traffic Engineering (TE)", RFC 4201, October 2005. - [9] Kompella, K. and G. Swallow, "Detecting Multi-Protocol Label - Switched (MPLS) Data Plane Failures", RFC 4379, February 2006. - - [10] Lang, J., Rekhter, Y., and D. Papadimitriou, "RSVP-TE + [9] Lang, J., Rekhter, Y., and D. Papadimitriou, "RSVP-TE Extensions in Support of End-to-End Generalized Multi-Protocol Label Switching (GMPLS) Recovery", RFC 4872, May 2007. - [11] Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow, "BFD + [10] Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow, "BFD For MPLS LSPs", draft-ietf-bfd-mpls-07 (work in progress), June 2008. - [12] Nadeau, T. and C. Pignataro, "Bidirectional Forwarding + [11] Nadeau, T. and C. Pignataro, "Bidirectional Forwarding Detection (BFD) for the Pseudowire Virtual Circuit Connectivity Verification (VCCV)", draft-ietf-pwe3-vccv-bfd-07 (work in progress), July 2009. 9.2. Informative References - [13] Vigoureux, M., Ward, D., and M. Betts, "Requirements for OAM in - MPLS Transport Networks", - draft-ietf-mpls-tp-oam-requirements-03 (work in progress), - August 2009. + [12] Vigoureux, M. and D. Ward, "Requirements for OAM in MPLS + Transport Networks", draft-ietf-mpls-tp-oam-requirements-06 + (work in progress), March 2010. + + [13] Kompella, K. and G. Swallow, "Detecting Multi-Protocol Label + Switched (MPLS) Data Plane Failures", RFC 4379, February 2006. [14] Ohta, H., "Assignment of the 'OAM Alert Label' for Multiprotocol Label Switching Architecture (MPLS) Operation and Maintenance (OAM) Functions", RFC 3429, November 2002. [15] Niven-Jenkins, B., Brungard, D., Betts, M., Sprecher, N., and S. Ueno, "MPLS-TP Requirements", draft-ietf-mpls-tp-requirements-10 (work in progress), August 2009. - [16] Bocci, M., Bryant, S., Frost, D., and L. Levrau, "A Framework - for MPLS in Transport Networks", - draft-ietf-mpls-tp-framework-06 (work in progress), - October 2009. + [16] Bocci, M., Bryant, S., Frost, D., Levrau, L., and L. Berger, "A + Framework for MPLS in Transport Networks", + draft-ietf-mpls-tp-framework-10 (work in progress), + February 2010. Authors' Addresses Matthew Bocci Alcatel-Lucent Voyager Place, Shoppenhangers Road Maidenhead, Berks SL6 2PJ UK Email: matthew.bocci@alcatel-lucent.com