MPLS Working Group F. Zhang, Ed. Internet-Draft ZTE Intended status: Standards Track R. Jing Expires: December 3, 2011 China Telecom June 01, 2011 RSVP-TE Extensions to Establish Associated Bidirectional LSP draft-ietf-ccamp-mpls-tp-rsvpte-ext-associated-lsp-01 Abstract The MPLS Transport Profile (MPLS-TP) requirements document [RFC5654], describes that MPLS-TP MUST support associated bidirectional point- to-point LSPs. This document provides a method to bind two unidirectional Label Switched Paths (LSPs) into an associated bidirectional LSP. The association is achieved by using a new Association Type in the Extended ASSOCIATION object. Status of this Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. 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." This Internet-Draft will expire on December 3, 2011. Copyright Notice Copyright (c) 2011 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 Zhang & Jing Expires December 3, 2011 [Page 1] Internet-Draft RSVP-TE Extensions of Associated LSP June 2011 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 described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Conventions used in this document . . . . . . . . . . . . . . 4 3. Association of Two Reverse Unidirectional LSPs . . . . . . . . 4 3.1. Provisioning Model . . . . . . . . . . . . . . . . . . . . 4 3.2. Signaling Procedure . . . . . . . . . . . . . . . . . . . 4 3.2.1. Single Sided Provisioning Model . . . . . . . . . . . 5 3.2.2. Double Sided Provisioning Model . . . . . . . . . . . 6 3.2.3. Asymmetric Bandwidth LSPs . . . . . . . . . . . . . . 8 3.2.3.1. Error Handling . . . . . . . . . . . . . . . . . . 9 3.3. Recovery Considerations . . . . . . . . . . . . . . . . . 10 4. Extensions to the Extended ASSOCIATION object . . . . . . . . 10 5. REVERSE_TSPEC Object . . . . . . . . . . . . . . . . . . . . . 13 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 6.1. Association Type . . . . . . . . . . . . . . . . . . . . . 13 6.2. REVERSE_TSPEC Object . . . . . . . . . . . . . . . . . . . 14 7. Security Considerations . . . . . . . . . . . . . . . . . . . 14 8. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 14 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 15 9.1. Normative references . . . . . . . . . . . . . . . . . . . 15 9.2. Informative References . . . . . . . . . . . . . . . . . . 15 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16 Zhang & Jing Expires December 3, 2011 [Page 2] Internet-Draft RSVP-TE Extensions of Associated LSP June 2011 1. Introduction The MPLS Transport Profile (MPLS-TP) requirements document [RFC5654] describes that MPLS-TP MUST support associated bidirectional point- to-point LSPs. Furthermore, an associated bidirectional LSP is useful for protection switching, for Operations, Administrations and Maintenance (OAM) messages that require a reply path. The requirements described in [RFC5654] are specifically mentioned in Section 2.1. (General Requirements), and are repeated below: 7. MPLS-TP MUST support associated bidirectional point-to-point LSPs. 11. The end points of an associated bidirectional LSP MUST be aware of the pairing relationship of the forward and reverse LSPs used to support the bidirectional service. 12. Nodes on the LSP of an associated bidirectional LSP where both the forward and backward directions transit the same node in the same (sub)layer as the LSP SHOULD be aware of the pairing relationship of the forward and the backward directions of the LSP. 14. MPLS-TP MUST support bidirectional LSPs with asymmetric bandwidth requirements, i.e., the amount of reserved bandwidth differs between the forward and backward directions. 50. The MPLS-TP control plane MUST support establishing associated bidirectional P2P LSP including configuration of protection functions and any associated maintenance functions. The above requirements are also repeated in [I-D.ietf-ccamp-mpls-tp-cp-framework]. The notion of association, as well as the corresponding Resource reSerVation Protocol (RSVP) ASSOCIATION object, is defined in [RFC4872], [RFC4873] and [I-D.ietf-ccamp-assoc-info] . In that context, the object is used to associate recovery LSPs with the LSP they are protecting. This object also has broader applicability as a mechanism to associate RSVP state, and [I-D.ietf-ccamp-assoc-ext] defines the Extended ASSOCIATION object that can be more generally applied. This document provides a method to bind two unidirectional Label Switched Paths (LSPs) into an associated bidirectional LSP. The association is achieved by using a new Association Type in the Extended ASSOCIATION object. Zhang & Jing Expires December 3, 2011 [Page 3] Internet-Draft RSVP-TE Extensions of Associated LSP June 2011 2. Conventions used in this document The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. 3. Association of Two Reverse Unidirectional LSPs 3.1. Provisioning Model The associated bidirectional LSP's forward and backward directions are set up, monitored, and protected independently as required by [RFC5654]. Configuration information regarding the LSPs can be sent to one end or both ends of the LSP. Depending on the method chosen, there are two models of signaling associated bidirectional LSP. The first model is the single sided provisioning, the second model is the double sided provisioning. For the single sided provisioning, the configurations are sent to one end. Firstly, a unidirectional tunnel is configured on this end, then a LSP under this tunnel is initiated with the Extended ASSOCIATION object carried in the Path message to trigger the peer end to set up the corresponding reverse TE tunnel and LSP. For the double sided provisioning, the two unidirectional TE tunnels are configured independently, then the LSPs under the tunnels are signaled with the Extended ASSOCIATION objects carried in the Path message to indicate each other to associate the two LSPs together to be an associated bidirectional LSP. A number of scenarios exist for binding LSPs together to be an associated bidirectional LSP. These include: (1) both of them do not exist; (2) both of them exist; (3) one LSP exists, but the other one need to be established. In all scenarios described, the provisioning models discussed above are applicable. 3.2. Signaling Procedure This section describes the signaling procedures for associating bidirectional LSPs. Consider the topology described in Figure 1. (An example of associated bidirectional LSP). The LSP1 [via nodes A,D,B] (from west to east) and LSP2 [via nodes B,D,C,A] (from east to west) are being established or have been established. These LSPs can be bound together to form an associated bidirectional LSP. Zhang & Jing Expires December 3, 2011 [Page 4] Internet-Draft RSVP-TE Extensions of Associated LSP June 2011 LSP1 is uniquely identified [I-D.ietf-mpls-tp-identifiers] by: West- Global_ID::West-Node_ID::West-Tunnel_Num::West-LSP_Num. LSP2 is uniquely identified [I-D.ietf-mpls-tp-identifiers] by: East- Global_ID::East-Node_ID::East-Tunnel_Num::East-LSP_Num. A-------D-------B \ / \ / \ / C Figure 1: An example of associated bidirectional LSP 3.2.1. Single Sided Provisioning Model For the single sided provisioning model, LSP1 is triggered by LSP2 or LSP2 is triggered by LSP1. When LSP2 is triggered by LSP1, according to the scenarios described above, the following cases may occur: 1. Both LSPs do not exist. LSP1 is initialized at node A with the Extended ASSOCIATION object inserted in the Path message, Association Type is set to "Association of two reverse unidirectional LSPs", Association ID set to West-LSP_Num, Association Source set to West-Node_ID, Global Association Source set to West-Global_ID, and Extended Association ID set to West-Tunnel_Num. Terminating node B is triggered to set up LSP2 by the received Extended ASSOCIATION object with the Association Type set to the value "Association of two reverse unidirectional LSPs", the Association Object inserted in LSP2's Path message is the same as in LSP1's Path message. 2. LSP1 exists, LSP2 needs to be established. LSP1 is refreshed with the Extended ASSOCIATION object inserted in the Path message, Association Type is set to "Association of two reverse unidirectional LSPs", Association ID set to West-LSP_Num, Association Source set to West-Node_ID, Global Association Source set to West-Global_ID, and Extended Association ID set to West- Tunnel_Num. Terminating node B is triggered to set up LSP2 by the received Extended ASSOCIATION object with the Association Type set to the value "Association of two reverse unidirectional LSPs", the Association Object inserted in LSP2's Path message is the same as in LSP1's Path message. Zhang & Jing Expires December 3, 2011 [Page 5] Internet-Draft RSVP-TE Extensions of Associated LSP June 2011 3. LSP1 does not exist, LSP2 has been established. LSP1 is initialized with the Extended ASSOCIATION object inserted in the Path message, Association Type is set to "Association of two reverse unidirectional LSPs", Association ID set to East- LSP_Num, Association Source set to East-Node_ID, Global Association Source set to East-Global_ID, and Extended Association ID set to East-Tunnel_Num. Terminating node B is triggered to refresh LSP2's Path message, with the received Extended ASSOCIATION object inserted. 4. Both LSP1 and LSP2 exist. LSP1 is refreshed with the Extended ASSOCIATION object inserted in the Path message, Association Type is set to "Association of two reverse unidirectional LSPs", Association ID set to East-LSP_Num, Association Source set to East-Node_ID, Global Association Source set to East-Global_ID, and Extended Association ID set to East- Tunnel_Num. Terminating node B is triggered to refresh LSP2's Path message, with the received Extended ASSOCIATION object inserted. When LSP1 is triggered by LSP2, the same rules are applicable. Based on the same values of the Association objects in the two LSPs' Path message, the two LSPs can be bound together to be an associated bidirectional LSP. 3.2.2. Double Sided Provisioning Model For the double sided provisioning model, Similarly, according to the scenarios described above, the following cases may occur: 1. LSP1 and LSP2 do not exist. LSP1 and LSP2 are concurrently initialized with the Extended ASSOCIATION object inserted in the their Path messages, For LSP1, Association Type is set to "Association of two reverse unidirectional LSPs", Association ID set to West-LSP_Num, Association Source set to West-Node_ID, Global Association Source set to West-Global_ID, and Extended Association ID set to West- Tunnel_Num. For LSP2, Association Type is set to "Association of two reverse unidirectional LSPs", Association ID is set to East- LSP_Num, Association Source set to East-Node_ID, Global Association Source set to East-Global_ID, and Extended Association ID set to East-Tunnel_Num. According to the general rules defined in [I-D.ietf-ccamp-assoc-ext], the two LSPs cannot be bound together to be an associated bidirectional LSP because of the different values. In this case, the two edge nodes firstly MUST compare their Global-Node_ID, then the bigger one sends Path refresh message, replacing the old Extended ASSOCIATION object with the new Extended ASSOCIATION object carried in the reverse LSP. Based on this Path refresh message, the two LSPs can be Zhang & Jing Expires December 3, 2011 [Page 6] Internet-Draft RSVP-TE Extensions of Associated LSP June 2011 bounded together to be an associated bidirectional LSP also. 2. LSP1 exists, LSP2 needs to be established. For LSP1, Association Type is set to "Association of two reverse unidirectional LSPs", Association ID set to West-LSP_Num, Association Source set to West-Node_ID, Global Association Source set to West-Global_ID, and Extended Association ID set to West- Tunnel_Num. For LSP2, Node B has known the existence of LSP1, so the Association Type is set to "Association of two reverse unidirectional LSPs", Association ID set to West-LSP_Num, Association Source set to West-Node_ID, Global Association Source set to West-Global_ID, and Extended Association ID set to West- Tunnel_Num. 3.LSP1 does not exist, LSP2 has been established. For LSP1, Node A has known the existenc of LSP2. So the Association Type is set to "Association of two reverse unidirectional LSPs", Association ID set to East-LSP_Num, Association Source set to East-Node_ID, Global Association Source set to East-Global_ID, and Extended Association ID set to East- Tunnel_Num. For LSP2, Node B does not know the existence of LSP1, so Association Type is set to "Association of two reverse unidirectional LSPs", Association ID set to East-LSP_Num, Association Source set to East-Node_ID, Global Association Source set to East-Global_ID, and Extended Association ID set to East- Tunnel_Num. 4. Both LSP1 and LSP2 exist. In this case, Both node A and Node B know the existence of the reverse LSPs. The two edge nodes firstly MUST compare their Global-Node_ID, then the bigger one sends Path refresh message, with the reverse LSP's identifier inserted in the Extended ASSOCIATION object, and the smaller one sends Path refresh message, with its own LSP's identifier inserted in the Extended ASSOCIATION object. For example, assuming that the node A has the bigger Global-Node_ID. For LSP1, the Association Type is set to "Association of two reverse unidirectional LSPs", Association ID set to East-LSP_Num, Association Source set to East-Node_ID, Global Association Source set to East-Global_ID, and Extended Association ID set to East-Tunnel_Num. For LSP2, the Association Type is set to "Association of two reverse unidirectional LSPs", Association ID set to West-LSP_Num, Association Source set to East-Node_ID, Global Association Source set to East-Global_ID, and Extended Association ID set to East-Tunnel_Num. Based on the same values of the Association objects in the two LSPs' Path message, the two LSPs can be bound together to be an associated bidirectional LSP. Zhang & Jing Expires December 3, 2011 [Page 7] Internet-Draft RSVP-TE Extensions of Associated LSP June 2011 3.2.3. Asymmetric Bandwidth LSPs A variety of applications, such as internet services and the return paths of OAM messages, exist and which MAY have different bandwidth requirements for each direction. Additional [RFC5654] also specifies an asymmetric bandwidth requirement. This requirement is specifically mentioned in Section 2.1. (General Requirements), and is repeated below: 14. MPLS-TP MUST support bidirectional LSPs with asymmetric bandwidth requirements, i.e., the amount of reserved bandwidth differs between the forward and backward directions. The approach for supporting asymmetric bandwidth co-routed bidirectional LSPs is defined in [I-D.ietf-ccamp-asymm-bw-bidir-lsps-bis], which introduces three new objects named UPSTREAM_FLOWSPEC object, UPSTREAM_TSPEC object and UPSTREAM_ADSPEC object to represent the asymmetric upstream traffic flow. For the asymmetric bandwidth associated bidirectional LSPs, the existing SENDER_TSPEC, ADSPEC, and FLOWSPEC are complemented with the addition of a new REVERSE_TSPEC object, which is used exactly in the same fashion as the old SENDER_TSPEC object. Consider the topology descirbed in Figure 1 in the context of asymmetric associated bidirectional LSP, the following cases may occur: 1. LSP1 and LSP2 do not exist. For the single sided provisioning, taking LSP2 triggered by LSP1 as an example. The REVERSE_TSPEC object MUST be carried in the LSP1's Path message together with the Extended ASSOCIATION object whose Association Type is "Association of two reverse unidirectional LSPs". The terminating node B is triggered to set up the reverse LSP2 with the corresponding asymmetric bandwidth, and the REVERSE_TSPEC object is converted to the SENDER_TSPEC object in the Path message. For the double sided provisioning, the REVERSE_TSPEC object MUST be carried in the two LSPs' Path message together with the Extended ASSOCIATION object whose Association Type is "Association of two reverse unidirectional LSPs". Then the two terminating ends MUST compare the values of the SENDER_TSPEC and REVERSE_TSPEC objects in the two Path messages. If the values match, the end with the bigger Global-Node_ID sends Path refresh message, carrying the Extended ASSOCIATION object of the reverse LSP. 2. LSP1 exists, LSP2 needs to be established. Zhang & Jing Expires December 3, 2011 [Page 8] Internet-Draft RSVP-TE Extensions of Associated LSP June 2011 For the single sided provisioning, taking LSP2 triggered by LSP1 as an example. The REVERSE_TSPEC object MUST be carried in the LSP1's Path refresh message together with the Extended ASSOCIATION object whose Association Type is "Association of two reverse unidirectional LSPs". The terminating node B is triggered to set up the reverse LSP2 with the corresponding asymmetric bandwidth, and the REVERSE_TSPEC object is converted to the SENDER_TSPEC object in the Path message. For the double sided provisioning, the REVERSE_TSPEC object MUST be carried in the LSP1's Path refresh message with the Extended ASSOCIATION object whose Association Type is "Association of two reverse unidirectional LSPs". There is no need to put the REVERSE_TSPEC object in LSP2's Path message, for the Extended ASSOCIATION object has indicated that LSP2 needs to be bound with LSP1. 3. LSP1 does not exist, LSP2 has been established. For the single sided provisioning, taking LSP2 triggered by LSP1 as an example. There is no need to put the REVERSE_TSPEC object in LSP1's Path message, for the Extended ASSOCIATION object has indicates that LSP1 needs to be bound with LSP2. For the double sided provisioning, just the same reason, the REVERSE_TSPEC object only needs to be carried in the LSP2's Path refresh message. 4. Both LSP1 and LSP2 exist. For the single sided provisioning, taking LSP2 triggered by LSP1 as an example. There is no need to put the REVERSE_TSPEC object in LSP1's Path message also for the Extended ASSOCIATION object has indicates that LSP1 needs to be bound with LSP2. As to the double sided provisioning, just the same reason, the REVERSE_TSPEC object does not need to be carried in the two LSPs' Path messages. Based on the same values of the Association objects in the two LSPs' Path message, and the match of the REVERSE_TSPEC and SENDER_TSPEC objects in the two LSPs' Path message (if the REVERSE_TSPEC object exists), the two LSPs can be bound together to be an associated bidirectional LSP. 3.2.3.1. Error Handling Nodes not supporting the new class number of the REVERSE_TSPEC object SHOULD respond with an "Unknown Object Class". Zhang & Jing Expires December 3, 2011 [Page 9] Internet-Draft RSVP-TE Extensions of Associated LSP June 2011 3.3. Recovery Considerations Consider the topology described in Figure 1, LSP1 and LSP2 form the associated bidirectional LSP. Under the scenario of recovery, a third LSP (LSP3) MAY be used to protect LSP1. LSP3 can be established before or after the failure occurs, it can share the same TE tunnel with LSP1 or not. In the case that LSP3 is established after the failure occurs, the Extended ASSOCIATION object with LSP2's identifier SHOULD be inserted in LSP3's Path message since LSP2 has already existed. If LSP1 and LSP2 are associated together by the LSP1's identifier, LSP2's Path message is refreshed, an additional Extended ASSOCIAION object with LSP2's identifier are inserted. If LSP1 and LSP2 are bound together by the LSP2's identifier, there is no need to insert an additional Extended ASSOCIATION object in LSP2's Path message. In the case that LSP3 is established before the failure occurs. For single sided provisioning, LSP3 is refreshed with the Extended ASSOCIATION object, its values are filled by LSP2's identifier. Then LSP2 is refreshed with this Extended ASSOCIATION object or not, see the description in the above paragraph. For double sided provisioning, if node A has the bigger Global-Node_ID than node B, LSP3 is refreshed with the Extended ASSOCIATION object whose values are filled by LSP2's identifier, and LSP2 is refreshed with this Extended ASSOCIATION object or not, see the description in the above paragraph. If node A has the smaller Global-Node_ID than node B, LSP3 is refreshed with the Extended ASSOCIATION object whose values are filled by LSP3's identifier, and LSP2 is refreshed with this Extended ASSOCIATION object. 4. Extensions to the Extended ASSOCIATION object The Extended ASSOCIATION object is defined in [I-D.ietf-ccamp-assoc-ext], which enables MPLS-TP required identification. The Extended IPv4 ASSOCIATION object (Class-Num of the form 11bbbbbb with value = 199, C-Type = TBA) has the format: Zhang & Jing Expires December 3, 2011 [Page 10] Internet-Draft RSVP-TE Extensions of Associated LSP June 2011 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Length | Class-Num(199)| C-Type (TBA) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Association Type | Association ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | IPv4 Association Source | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Global Association Source | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ : . : : Extended Association ID : : . : +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Extended IPv4 ASSOCIATION object The Extended IPv6 ASSOCIATION object (Class-Num of the form 11bbbbbb with value = 199, C-Type = TBA) has the format: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Length | Class-Num(199)| C-Type (TBA) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Association Type | Association ID | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | IPv6 Association Source | | | | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Global Association Source | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ : . : : Extended Association ID : : . : +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Extended IPv6 ASSOCIATION object o Association Type: Zhang & Jing Expires December 3, 2011 [Page 11] Internet-Draft RSVP-TE Extensions of Associated LSP June 2011 In order to bind two reverse unidirectional LSPs to be an associated bidirectional LSP, this document defines a new Association Type: Value Type ----- ----- 4 (TBD) Association of two reverse unidirectional LSPs (A) If the downstream nodes are not aware of the Association Type, they MUST return a PathErr message with error code/sub-code "LSP Admission Failure/Bad Association Type". Under the context of this Association Type, any node associating an associated bidirectional LSP MUST insert an ASSOCIATION object with the following setting: o Association ID: The Association ID MUST be set to its own signaled LSP ID (default); if known, it MAY be set to the LSP ID of the associated reverse LSP. o Association Source: The Association source MUST be set to the tunnel sender address of this LSP (default); if known, it May be set to the tunnel sender address of the peer node. o Global Association Source: The format is described in [I-D.ietf-ccamp-assoc-ext]. o Extended Association ID: Because the two LSPs (one is from west to east, and the other is from east to west) are in different tunnels, the Association ID is insufficient to uniquely identify association for associated bidirectional LSP. Hence, this document adds specific rules: the first 16-bits MUST be set to its own tunnel ID (default); if known, it May be set to the tunnel ID of the the associated reverse tunnel. As described in [I-D.ietf-ccamp-assoc-ext], association is always done based on matching Path state or Resv state. Upstream initializted association is represented in Extended ASSOCIATION objects carried in Path message and downstream initializted Zhang & Jing Expires December 3, 2011 [Page 12] Internet-Draft RSVP-TE Extensions of Associated LSP June 2011 association is represented in Extended ASSOCIATION objects carried in Resv messages. The new defined association type in this document is only defined for use in upstream initialized association. Thus it can only appear in Extended ASSOCIATION objects signaled in Path message. The rules associated with the processing of the Extended ASSOCIATION objects in RSVP message are discussed in [I-D.ietf-ccamp-assoc-ext]. It said that in the absence of Association Type-specific rules for identifying association, the included Extended ASSOCIATION objects MUST be identical. This document adds no specific rules, the association will always operate based on the same Extended ASSOCIATION objects. 5. REVERSE_TSPEC Object The REVERSE_TSPEC object is used in Path, PathTear, PathErr, and Notify message (via sender descriptor). This includes the definition of class type and format. It's class number is TBD (of the form 0bbbbbbb), and class type and format is the same as the SENDER_TSPEC object. This object modifies the RSVP message-related formats defined in [RFC2205], [RFC3209] and [RFC3473]. See [RFC5511] for the syntax used by RSVP. The format of the sender description for asymmetric associated bidirectional LSPs is: ::= [] [] [] [] 6. IANA Considerations IANA is requested to administer assignment of new values for namespace defined in this document and summarized in this section. 6.1. Association Type Within the current document, a new Association Type is defined in the Extended ASSOCIATION object. Zhang & Jing Expires December 3, 2011 [Page 13] Internet-Draft RSVP-TE Extensions of Associated LSP June 2011 Value Type ----- ----- 4 (TBD) Association of two reverse unidirectional LSPs (A) 6.2. REVERSE_TSPEC Object A new class named REVERSE_TSPEC has been created in the 0bbbbbbb rang (123,TBD) with the following definition: Class Types or C-types: Same values as SENDER_TPSCE object (C-Num 12) There are no other IANA considerations introduced by this document. 7. Security Considerations This document introduces a new association type, and except this, there are no security issues about the Extended ASSOCIATION object are introduced here. Furthermore, this document introduces the REVERSE_TSPEC object for use in GMPLS signaling [RFC3473], which is parallel the existing SENDER_TSPEC object. As such, any vulnerabilities that are due to the use of the old SENDER_TSPEC object now apply here also. Otherwise, this document introduces no additional security considerations. For a general discussion on MPLS and GMPLS related security issues, see the MPLS/GMPLS security framework [RFC5920]. 8. Acknowledgement The authors would like to thank Lou Berger for his great guidance in this work, George Swallow and Jie Dong for the discussion of recovery, Lamberto Sterling for his valuable comments on the section of asymmetric bandwidths, Daniel King for the review of the document, Attila Takacs for the discussion of the provisioning model. At the same time, the authors would also like to acknowledge the contributions of Bo Wu, Xihua Fu, Lizhong Jin, and Wenjuan He for the initial discussions. 9. References Zhang & Jing Expires December 3, 2011 [Page 14] Internet-Draft RSVP-TE Extensions of Associated LSP June 2011 9.1. Normative references [I-D.ietf-ccamp-assoc-ext] Berger, L., Faucheur, F., and A. Narayanan, "RSVP Association Object Extensions", draft-ietf-ccamp-assoc-ext-00 (work in progress), May 2011. [I-D.ietf-mpls-tp-identifiers] Bocci, M., Swallow, G., and E. Gray, "MPLS-TP Identifiers", draft-ietf-mpls-tp-identifiers-04 (work in progress), March 2011. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC4872] 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. [RFC4873] Berger, L., Bryskin, I., Papadimitriou, D., and A. Farrel, "GMPLS Segment Recovery", RFC 4873, May 2007. [RFC5654] Niven-Jenkins, B., Brungard, D., Betts, M., Sprecher, N., and S. Ueno, "Requirements of an MPLS Transport Profile", RFC 5654, September 2009. 9.2. Informative References [I-D.ietf-ccamp-assoc-info] Berger, L., "Usage of The RSVP Association Object", draft-ietf-ccamp-assoc-info-02 (work in progress), May 2011. [I-D.ietf-ccamp-asymm-bw-bidir-lsps-bis] Takacs, A., Berger, L., Caviglia, D., Fedyk, D., and J. Meuric, "GMPLS Asymmetric Bandwidth Bidirectional Label Switched Paths (LSPs)", draft-ietf-ccamp-asymm-bw-bidir-lsps-bis-01 (work in progress), January 2011. [I-D.ietf-ccamp-mpls-tp-cp-framework] Andersson, L., Berger, L., Fang, L., Bitar, N., Gray, E., Takacs, A., Vigoureux, M., and E. Bellagamba, "MPLS-TP Control Plane Framework", draft-ietf-ccamp-mpls-tp-cp-framework-06 (work in progress), February 2011. Zhang & Jing Expires December 3, 2011 [Page 15] Internet-Draft RSVP-TE Extensions of Associated LSP June 2011 [RFC2205] Braden, B., Zhang, L., Berson, S., Herzog, S., and S. Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1 Functional Specification", RFC 2205, September 1997. [RFC3209] 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. [RFC3473] Berger, L., "Generalized Multi-Protocol Label Switching (GMPLS) Signaling Resource ReserVation Protocol-Traffic Engineering (RSVP-TE) Extensions", RFC 3473, January 2003. [RFC5511] Farrel, A., "Routing Backus-Naur Form (RBNF): A Syntax Used to Form Encoding Rules in Various Routing Protocol Specifications", RFC 5511, April 2009. [RFC5920] Fang, L., "Security Framework for MPLS and GMPLS Networks", RFC 5920, July 2010. Authors' Addresses Fei Zhang (editor) ZTE Email: zhang.fei3@zte.com.cn Ruiquan Jing China Telecom Email: jingrq@ctbri.com.cn Fan Yang ZTE Email: yang.fan5@zte.com.cn Weilian Jiang ZTE Email: jiang.weilian@zte.com.cn Zhang & Jing Expires December 3, 2011 [Page 16]