CCAMP Working Group CCAMP GMPLS P&R Design Team Internet Draft Expiration Date: November 2003 J.P. Lang (Editor) Y. Rekhter (Editor) May 2003 RSVP-TE Extensions in support of End-to-End GMPLS-based Recovery draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet- Drafts as reference material or to cite them other than as "work in progress." 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. For potential updates to the above required-text see: http://www.ietf.org/ietf/1id-guidelines.txt Abstract This document describes protocol specific procedures for GMPLS (Generalized Multi-Protocol Label Switching) RSVP-TE (Resource ReserVation Protocol - Traffic Engineering) signaling extensions to support end-to-end LSP protection and restoration. A generic functional description of GMPLS recovery can be found in a companion document. J.P.Lang et al. - Internet Draft û Expires November 2003 1 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 1. Contributors This document is the result of the CCAMP Working Group Protection and Restoration design team joint effort. The following are the authors that contributed to the present memo: Deborah Brungard (AT&T) Rm. D1-3C22 - 200 S. Laurel Ave. Middletown, NJ 07748, USA E-mail: dbrungard@att.com Sudheer Dharanikota (Consult) E-mail: sudheer@ieee.org Jonathan Lang (Rincon Networks) E-mail: jplang@ieee.org Guangzhi Li (AT&T) 180 Park Avenue, Florham Park, NJ 07932, USA E-mail: gli@research.att.com Eric Mannie (Consult) Email: eric_mannie@hotmail.com Dimitri Papadimitriou (Alcatel) Fr. Wellesplein, 1 B-2018, Antwerpen, Belgium Email: dimitri.papadimitriou@alcatel.be Bala Rajagopalan (Tellium) 2 Crescent Place - P.O. Box 901 Oceanport, NJ 07757-0901, USA E-mail: braja@tellium.com Yakov Rekhter (Juniper) 1194 N. Mathilda Avenue Sunnyvale, CA 94089, USA E-mail: yakov@juniper.net J.P.Lang et al. - Internet Draft û Expires November 2003 2 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 2. Introduction Generalized Multi-Protocol Label Switching (GMPLS) extends MPLS to include support for Layer-2 (L2SC), Time-Division Multiplex (TDM), Lambda Switch Capable (LSC), and Fiber Switch Capable (FSC) interfaces. GMPLS-based recovery uses control plane mechanisms (i.e., signaling, routing, link management mechanisms) to support data plane fault recovery. Note that the analogous (data plane) fault detection mechanisms are required to be present in support of the control plane mechanisms. In this document, the term "recovery" is generically used to denote both protection and restoration; the specific terms "protection" and "restoration" are only used when differentiation is required. The subtle distinction between protection and restoration is made based on the resource allocation done during the recovery phase (see [TERM]). A functional description of GMPLS-based recovery is provided in [FUNCT] and should be considered as a companion document to this memo which describes the protocol specific procedures for GMPLS RSVP-TE (Resource ReSerVation Protocol - Traffic Engineering) signaling (see [RFC-3473]) to support end-to-end recovery of an entire LSP from the head-end to the tail-end. The present memo addresses four types of end-to-end LSP recovery: 1+1 unidirectional/ 1+1 bi-directional protection, LSP protection with extra-traffic (including 1:1 protection with extra-traffic), pre-planned LSP re- routing without extra-traffic (including shared mesh) and full LSP re-routing. The simplest notion of end-to-end LSP protection is the 1+1 unidirectional protection. Using this type of protection, a protecting LSP is signaled over a dedicated resource-disjoint alternate path to protect an associated working LSP. Normal traffic is simultaneously sent on both LSPs and a selector is used at the egress node to receive traffic from one of the LSPs. If a failure occurs along one of the LSPs, the egress node selects the traffic from the valid LSP. No coordination is required between the end nodes when a failure/switchover occurs. In 1+1 bi-directional protection, a protecting LSP is signaled over a dedicated resource-disjoint alternate path to protect the working LSP. Normal traffic is simultaneously sent on both LSPs and a selector is used at both ingress/egress nodes to receive traffic from the same LSP. This requires co-ordination between the end nodes when switching to the protecting LSP. Pre-planned LSP restoration or re-routing (without extra-traffic) relies on the establishment between the same end points of a working LSP and a protecting LSP that is link/node/SRLG disjoint from the working one. Here, the recovery resources for the protecting LSPs are pre-reserved and explicit action is required to activate (i.e. commit resource allocation at the data plane) a specific protecting LSP instantiated during the (pre-)provisioning phase. Since the J.P.Lang et al. - Internet Draft û Expires November 2003 3 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 protecting LSP is not activated, it can not carry any extra-traffic. Therefore, this mechanism protects against working LSP failure(s) but requires activation of the protecting LSP after failure occurrence. This requires restoration signaling along the protecting path. "Shared-mesh" restoration can be seen as a particular case of pre-planned LSP re-routing that reduces the recovery resource requirements by allowing multiple protecting LSPs to share common link and node resources. Similarly, the recovery resources are pre- reserved and explicit action is required to activate (i.e. commit resource allocation at the data plane) a specific protecting LSP instantiated during the (pre-)provisioning phase. This procedure requires restoration signaling along the protecting path. Last, full LSP restoration or re-routing, on the other hand, switches normal traffic to an alternate LSP fully established after failure occurrence. The new alternate route is selected at the LSP head-end, it may reuse intermediate node's resources of the failed LSP and may include additional intermediate nodes and/or links. Note that crankback signaling and intermediate LSP recovery are further detailed in dedicated companion documents. 3. 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]. In addition, the reader is assumed to be familiar with the terminology used in [GMPLS-ARCH], [RFC-3471], [RFC-3473] and referenced as well as [TERM] and [FUNCT]. 4. Identification 4.1 LSP Identification LSP tunnels are identified by a combination of the SESSION and SENDER_TEMPLATE objects (see also [RFC-3209]). The relevant fields are as follows: IPv4 (or IPv6) tunnel end point address IPv4 (or IPv6) address of the egress node for the tunnel. Tunnel ID A 16-bit identifier used in the SESSION that remains constant over the life of the tunnel. Extended Tunnel ID A 32-bit (or 16-byte) identifier used in the SESSION that J.P.Lang et al. - Internet Draft û Expires November 2003 4 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 remains constant over the life of the tunnel. Normally set to all zeros. Ingress nodes that wish to narrow the scope of a SESSION to the ingress-egress pair MAY place their IPv4 (or IPv6) address here as a globally unique identifier. IPv4 (or IPv6) tunnel sender address IPv4 (or IPv6) address for a sender node. LSP ID A 16-bit identifier used in the SENDER_TEMPLATE and FILTER_SPEC that can be changed to allow a sender to share resources with itself. The first three fields are carried in the SESSION object (Path and Resv message) and constitute the basic identification of the LSP tunnel. The last two fields are carried in the SENDER_TEMPLATE (Path message) and FILTER_SPEC objects (Resv message). The LSP ID is used to differentiate LSP tunnels that belong to the same session. 4.2 Recovery Identification This is done using the following fields in the PROTECTION object (see also Section 14). 4.2.1 LSP Status The following bits are used in determining resource allocation and status of the LSP within the group of LSPs forming the protected entity: - S (Secondary) bit: enables distinction between primary and secondary LSPs. A primary LSP is a fully established LSP (for which resource allocation and cross-connection have been committed). Both working and protecting LSPs can be primary LSPs. A secondary LSP is a control plane provisioned only LSP for which resource allocation MAY have been done but for which no cross- connection has been performed. Only protecting LSPs can be secondary LSPs. - P (Protecting) bit: enables distinction between working and protecting LSPs. A working LSP must be a primary LSP whilst a protecting LSP can be either a primary or a secondary LSP. When protecting LSP(s) are associated to working LSP(s), one also refers to the latter as protected LSPs. Note: The combination "secondary working" is not valid (only protecting LSPs can be secondary LSPs). Working LSPs are always J.P.Lang et al. - Internet Draft û Expires November 2003 5 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 primary LSPs (i.e. fully established) whilst primary LSPs can be either working or protecting LSPs. 4.2.2 LSP Recovery The following classification is used to distinguish the LSP Protection Type to which LSPs can be associated at end-nodes (a distinct value is associated to each of them in the PROTECTION object, see Section 14): - Full LSP Re-routing: set if the primary working LSPs are dynamically recoverable using (non pre-planned) head-end re- routing. - (Pre-planned) LSP Re-routing without Extra-traffic: set if the protecting LSPs are secondary LSPs that allows for sharing of the recovery resources between one or more than one pair. When secondary LSPs resources are not dedicated to a single pair, one refers to shared mesh recovery. - LSP Protection with Extra-traffic: set if the protecting LSPs are dedicated primary LSPs that do allow for extra-traffic transport and thus precluding any sharing of the recovery resources between more than one pair. This type includes 1:1 path protection with extra-traffic. - Dedicated LSP Protection: set if the protecting LSPs do not allow sharing of the recovery resources nor the transport of extra- traffic (implying in the present context, duplication of the signal over both working and protecting LSPs). Note also that this document makes a distinction between unidirectional and bi- directional dedicated LSP protection. For LSP protection, in particular when the data plane provides automated protection switching capability (see for instance ITU-T G.841 Recommendation), a Notification (N) bit is defined in the PROTECTION object. It allows for distinction between protection switching signaling via the control plane or via the data plane. Note: this document assumes that Protection Type values are end-to- end significant and that the same value is sent over the protected and the protecting path. In this context, shared-mesh for instance, appears from the end-nodes perspective as being simply an LSP re- routing without extra-traffic service. The net result of this is that a single bit (the S bit alone) does not allow differentiating whether resource allocation should be performed *with respect to* the status of the LSP within the protected entity. The introduction of the P bit solves unambiguously this problem. These bits MUST be processed on a hop-by-hop basis (independently of the LSP Protection Type context). This allows for an easier implementation of reversion signaling (see Section 12) but also transparent delivery of protected services since any intermediate node is not required to J.P.Lang et al. - Internet Draft û Expires November 2003 6 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 know the semantic associated with the incoming LSP Protection Type value. 4.2.3 LSP Association When used for the working LSP signaling, the Associated LSP ID identifies the protecting LSP. When used for the protecting LSP signaling, this field identifies the LSP protected by this LSP. 5. 1+1 Unidirectional Protection One of the simplest notions of end-to-end LSP protection is 1+1 unidirectional protection. Consider the following network topology: A---B---C---D \ / E---F---G The paths [A,B,C,D] and [A,E,F,G,D] are node and link disjoint, ignoring the ingress/egress nodes A and D. A 1+1 protected path is established from A to D over [A,B,C,D] and [A,E,F,G,D] and traffic is transmitted simultaneously over both component paths (i.e. LSPs). When a failure occurs (say at node B) and is detected at end-node D, the receiver at D selects the normal traffic from the other LSP. From this perspective, 1+1 unidirectional protection can be seen as an uncoordinated protection switching mechanism acting independently at both end-points. Note also that both LSPs are instantiated and activated so that no resource sharing can be done along the protecting LSP (nor can any extra-traffic be transported). It is also RECOMMENDED to set the N bit since no protection switching signaling is assumed in the present case. Also, for the protected LSP under failure condition, the Path_State_Remove Flag of the ERROR_SPEC object (see [RFC-3473]) SHOULD NOT be set upon PathErr message generation. Note: one should assume that both paths are SRLG disjoint otherwise, a failure would impact both working and protecting LSPs. 5.1. Identifiers Since both LSPs correspond to the same session, the SESSION object MUST be the same for both LSPs. The LSP ID, however, MUST be different to distinguish between the two LSPs. A new PROTECTION object is included in the Path message. This object carries the desired end-to-end LSP Protection Type (in this case, "1+1 Unidirectional") as well as the LSP ID of the associated LSP J.P.Lang et al. - Internet Draft û Expires November 2003 7 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 referred to as the Associated LSP ID. This LSP Protection Type value is applicable to both uni- and bi-directional LSPs. It is also desirable to allow distinguishing the working (LSP from which the signal is taken) from the protecting LSP. This is achieved for the working LSP by setting in the PROTECTION object the S bit to 0, the P bit to 0 and the Associated LSP ID to the protecting LSP_ID. The protecting LSP is signaled by setting in this object the S bit to 0, the P bit to 1 and the Associated LSP ID to the associated protected LSP_ID. After protection switching completes, to keep track of the LSP from which the signal is taken, the former protecting LSP SHOULD be signaled as the working LSP from the head-end node (upon reception of the PathErr message). For the same reason, the former working LSP SHOULD be signaled as the protecting LSP with the A bit set in the ADMIN_STATUS object (see [RFC-3473]). 6. 1+1 Bi-directional Protection 1+1 bi-directional protection is another scheme that provides end- to-end LSP protection. Consider the following network topology: A---B---C---D \ / E---F---G The LSPs [A,B,C,D] and [A,E,F,G,D] are node and link disjoint, ignoring the ingress/egress nodes A and D. A bi-directional LSP is established from A to D over each path and traffic is transmitted simultaneously over both LSPs. In this scheme, both end-points must receive traffic over the same LSP. When a failure is detected by one or both end-points of the LSP, both end-points must select traffic from the other LSP. This action must be coordinated between node A and D. From this perspective, 1+1 bi-directional protection can be seen as a coordinated protection switching mechanism between both end-points. Note also that both LSPs are instantiated and activated so that no resource sharing can be done along the protection path (nor can any extra-traffic be transported). Note: one should assume that both paths are SRLG disjoint otherwise a failure would impact both working and protecting LSPs. 6.1. Identifiers Since both LSPs correspond to the same session, the SESSION object MUST be the same in both LSPs. The LSP ID, however, MUST be different to distinguish between the two LSPs. J.P.Lang et al. - Internet Draft û Expires November 2003 8 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 A new PROTECTION object is included in the Path message. This object carries the desired end-to-end LSP Protection Type (in this case, "1+1 Bi-directional") as well as the LSP ID of the associated LSP referred to as Associated LSP ID. This LSP Protection Type value is only applicable to bi-directional LSPs. It is also desirable to allow distinguishing the working (LSP from which the signal is taken) from the protecting LSP. This is achieved for the working LSP by setting in the PROTECTION object the S bit to 0, the P bit to 0 and the Associated LSP ID to the protecting LSP_ID. The protecting LSP is signaled by setting in this object the S bit to 0, the P bit to 1 and the Associated LSP ID to the associated protected LSP_ID. 6.2. End-to-End Switchover Request/Response To co-ordinate the switchover between endpoints, an end-to-end switchover request is needed since a failure affecting one the LSPs results in both endpoints switching to the LSP (or equivalently the traffic) in their respective direction. This is done using the Notify message with a new Error Code indicating "Working Path Failure; Switchover Request". The Notify Ack message MUST be sent to confirm the reception of the Notify message. The procedure is as follows: 1. If an end-node (A or D) detects the failure of the working LSP (or a degradation of signal quality over the working LSP) or receives a Notify message including its SESSION object within the (see [RFC-3473]), it MUST begin receiving on the protection LSP and send a Notify message reliably to the other end-node (D or A, respectively). This message MAY indicate the identity of the failed working link and other relevant information using the IF_ID ERROR_SPEC (see [RFC-3473]). Note: in this case, the IF_ID ERROR_SPEC replaces the ERROR_SPEC in the Notify message, otherwise the corresponding (data plane) information is to be received in the PathErr/ResvErr message. 2. Upon receipt of the switchover message, the end-node (D or A, respectively) MUST begin receiving from the protection LSP and send a (Notify) Ack message to the other end-node (A or D, respectively) using reliable message delivery (see [RFC-2961]). Since the intermediate nodes (B,C,E,F and G) are assumed to be GMPLS signaling capable, each node adjacent to the failure MAY generate a Notify message directed either to the LSP head-end (upstream direction) or the LSP tail-end (downstream direction) or even both. J.P.Lang et al. - Internet Draft û Expires November 2003 9 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 Therefore, it is expected that these LSP terminating nodes (that MAY also detect the failure of the LSP from the data plane) provide either the right correlation mechanism to avoid repetition of the above procedure or just discard subsequent Notify messages corresponding to the same Session. In addition, for the working LSP under failure, the Path_State_Remove Flag of the ERROR_SPEC object (see [RFC-3473]) SHOULD NOT be set upon PathErr message generation. After protection switching completes (step 2), to keep track of the LSP from which the signal is taken, the former protecting LSP SHOULD be signaled as the working LSP. For the same reason, the former working LSP SHOULD be signaled as the protecting LSP with the A bit set in the ADMIN_STATUS object (see [RFC-3473]). Note: when the N bit is set, the above end-to-end switchover request/response exchange does only provide control plane coordination (no actions are triggered at the data plane level). 7. 1:1 Protection with Extra-Traffic The most common notion of end-to-end 1:1 protection is to establish, between the same endpoints, a working LSP and a protecting LSP that are mutually link/node/SRLG disjoint. This protects against working LSP failure(s). An important feature of GMPLS signaling is that it allows pre- provisioning of protecting LSPs to protect working LSPs. This is done by indicating in the Path message (in the newly defined PROTECTION object, see Section 14) that the LSPs are of type working and protecting, respectively. Protecting LSPs are used for fast switchover when working LSPs fail. In this case, working and protecting LSPs are both signaled as primary LSPs; they are fully instantiated during the provisioning phase. Although the resources for the protecting LSPs are pre-allocated lower priority traffic may use these resources (i.e. the protecting LSP are capable to carry extra-traffic) with the caveat that the lower priority traffic will be preempted if the working LSP fails. If lower priority traffic is using resources along the protecting LSPs, the end-nodes may need to be notified of the failure in order to complete the switchover. The setup of the working LSP SHOULD indicate that the LSP head-end and tail-end node wish to receive Notify messages using the Notify Request object. The upstream node (upstream in terms of the direction an RSVP Path message traverses) SHOULD send an RSVP Notify message to the LSP head-end, and the downstream node SHOULD send an RSVP Notify message to the LSP tail-end. Upon receipt of the Notify messages, both the end-nodes MUST switch the (normal) traffic from the working LSP to the pre-configured protecting LSP (see Section 7.2). Note that if the working and the protecting LSP are J.P.Lang et al. - Internet Draft û Expires November 2003 10 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 established between the same end-nodes no further notification is required to indicate that the working LSPs are no longer protected. Consider the following topology: A---B---C---D \ / E---F---G The working LSP [A,B,C,D] could be protected by the protecting LSP [A,E,F,G,D]. Both LSPs are instantiated (resources are allocated for both working and protecting LSPs) and no resource sharing can be done along the protection path since the primary protecting LSP can carry extra-traffic. Note: one should assume that both paths are SRLG disjoint otherwise a failure would impact both working and protecting LSPs. 7.1 Identifiers Since both LSPs correspond to the same session, the SESSION object MUST be the same in both LSPs. The LSP ID, however, MUST be different to distinguish between the protected LSP carrying working traffic and the protecting LSP that can carry extra-traffic. A new PROTECTION object is included in the Path message used to setup the two LSPs. This object carries the desired end-to-end LSP Protection Type (in this case, "1:1 Protection with Extra-Traffic"). This LSP Protection Type value is applicable to both uni- and bi- directional LSPs. The working LSP is signaled by setting in this object the S bit to 0, the P bit to 0 and the Associated LSP ID to the protecting LSP_ID. The protecting LSP is signaled by setting in this object the S bit to 0, the P bit to 1 and the Associated LSP ID to the associated protected LSP_ID. 7.2 End-to-End Switchover Request/Response To co-ordinate the switchover between endpoints, an end-to-end switchover request is needed such that the affected LSP(s) are moved to the protecting LSP. Protection switching from the working to the protecting LSP (implying preemption of extra-traffic carried over the protecting LSP) must be initiated by one of the end-point nodes (A or D) or simply end-nodes. This operation may be done using Notify message exchange with a new Error Code indicating "Working Path Failure; Switchover Request". The Notify Ack message MUST be sent to confirm the reception of the Notify message. J.P.Lang et al. - Internet Draft û Expires November 2003 11 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 The procedure is as follows: 1. If an end-node (A or D) detects the failure of the working LSP (or a degradation of signal quality over the working LSP) or receives a Notify message including its SESSION object within the (see [RFC-3473]), it disconnects the extra-traffic from the protecting LSP and send a Notify message reliably to the other end-node (D or A, respectively). This message MAY indicate the identity of the failed working link and other relevant information using the IF_ID ERROR_SPEC (see [RFC- 3473]). Note: in this case, the IF_ID ERROR_SPEC replaces the ERROR_SPEC in the Notify message, otherwise the corresponding information is to be received in the PathErr/ResvErr message 2. Upon receipt of the switchover (i.e. Notify) message, the end-node (D or A, respectively) MUST disconnect the extra- traffic from the protecting LSP and begin sending/receiving normal traffic out/from the protecting LSP and send a (Notify) Ack message to the other end-node (A or D, respectively) using reliable message delivery (see [RFC 2961]). Also, the Notify message generated by the end-node is distinguishable from the one generated by an intermediate node, there is no possibility of connecting the extra traffic to the working LSP due to the receipt of Notify message from an intermediate node. 3. Upon receipt of the (Notify) Ack message, the end-node (A or D, respectively) MUST begin receiving normal traffic from the protecting LSP. Note 1: a 2-phase protection switching signaling is used in the present context, a 3-phase signaling (see [FUNCT]) that would imply a notification message and a switchover request/response messages, is not considered here. Also, when the protecting LSPs do not carry extra-traffic, a 1-Phase protection switching signaling as defined in Section 6.2 MAY be used instead of the 2-Phase described here above. Note 2: when the N bit is set, the above end-to-end switchover request/response exchange does only provide control plane coordination (no actions are triggered at the data plane level). After protection switching completes (step 3), the formerly working LSP SHOULD be signaled with the A bit set in the ADMIN_STATUS object (see [RFC-3473]). 8. 1:1 Re-routing without Extra-Traffic J.P.Lang et al. - Internet Draft û Expires November 2003 12 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 End-to-end LSP 1:1 re-routing without Extra-Traffic relies on the establishment between the same endpoints of a working LSP and a protecting LSP that is link/node/SRLG disjoint from the working one. However, in this case the protecting LSP is not instantiated, thus, it can not carry any extra-traffic. Therefore, this mechanism protects against working LSP failure(s) but requires instantiation of the protecting LSP after failure occurrence. Signalling is performed by indicating in the Path message (in the newly defined PROTECTION object, see Section 14) that the LSPs are of type working and protecting, respectively. Protecting LSPs are used for fast switchover when working LSPs fail. In this case, working and protecting LSPs are signaled as primary LSP and secondary LSP, respectively. Thus, only the working LSP is fully instantiated during the provisioning phase and for the protecting LSPs, no resources are pre-allocated (they are pre-reserved at the control plane level only). The setup of the working LSP SHOULD indicate (using the NOTIFY REQUEST object as specified in Section 4 of [RFC-3473]) that the LSP head-end node (and possibly the tail-end node) wish to receive a Notify message upon LSP failure occurrence. Upon receipt of the Notify message, the head-end node MUST switch the (normal) traffic from the working LSP to the protecting LSP after its activation. Note that since the working and the protecting LSP are established between the same end-nodes no further notification is required to indicate that the working LSPs are no longer protected. Consider the following topology: A---B---C---D \ / E---F---G The working LSP [A,B,C,D] could be protected by the protecting LSP [A,E,F,G,D]. Only the protected LSP is instantiated (resources are only allocated for the working LSP) therefore, the protecting LSP can not carry any extra-traffic. When a failure is detected on the working LSP (say at B), the error is propagated and/or notified to the ingress node (A), which activates the secondary protecting LSP instantiated during the provisioning phase. This requires: (1) the ability to identify a "secondary protecting LSP" (hereby called the "secondary LSP") used to recover another primary working LSP (hereby called the "protected LSP") (2) the ability to associate the secondary LSP with the protected LSP (3) the capability to activate a secondary LSP after failure occurrence. In the following subsections, these features are described in more detail. J.P.Lang et al. - Internet Draft û Expires November 2003 13 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 8.1 Identifiers Since both LSPs correspond to the same session, the SESSION object MUST be the same in both LSPs. The LSP ID, however, MUST be different to distinguish between the two LSPs, here the protected LSP carrying working traffic and the protecting LSP that can not carry extra-traffic. A new PROTECTION object is used to setup the two LSPs. This object carries the desired end-to-end LSP Protection Type in this case, "1:1 Re-routing without Extra-Traffic") as well as the LSP ID of the associated LSP. This LSP Protection Type value is applicable to both uni- and bi-directional LSPs. 8.2 Signaling Primary LSPs The PROTECTION object is included in the Path message during signaling of the primary working LSP, with the end-to-end LSP Protection Type set to "1:1 Re-routing without Extra-Traffic". The primary working LSP is signaled by setting in this object the S bit to 0, the P bit to 0 and the Associated LSP ID to the protecting LSP_ID. 8.3 Signaling Secondary LSPs Secondary LSPs are signaled using the S bit of the new PROTECTION object that is carried. If set, the resources for the secondary LSP SHOULD be (pre-)reserved, but not committed at the data plane level meaning that the internals of the switch need not be established until explicit action is taken to activate this secondary LSP. Activation of a secondary LSP is done using a Path refresh message with the S bit set to 0 in the PROTECTION object. At this point, the link and node resources must to be allocated for the LSP that becomes a primary working LSP (ready to carry normal traffic). Two cases have to be covered here (see also [GMPLS-ARCH]) since secondary protecting LSPs can be setup with resource reservation but with or without label pre-selection (both allowing sharing of the recovery resources). In the former case (defined as the default), secondary LSP signaling does not necessitate any specific procedure compared to the one defined in [RFC-3473]. However, in the latter case, label (and thus resource) re-allocation MAY occur during the secondary LSP activation. This means that during the activation phase, labels MAY be re-assigned (with higher precedence over label assignment, see also [RFC-3471]). 9. Shared Mesh Restoration An approach to reduce recovery resource requirements is to have protection LSPs sharing network resources when the working LSPs that they protect are physically (i.e., link, node, SRLG, etc.) disjoint. J.P.Lang et al. - Internet Draft û Expires November 2003 14 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 This mechanism is referred to as shared mesh restoration and is described in [FUNCT]. Shared-mesh restoration can be seen as particular case of pre-planned LSP re-routing that reduces the recovery resource requirements by allowing multiple working LSPs to share common link and node resources. Here also, the recovery resources for the protecting LSPs are pre-reserved during the provisioning phase, but explicit (signaling) action is required to activate (i.e. commit resource allocation at the data plane) a specific protecting LSP instantiated during the provisioning phase. This requires restoration signaling along the protecting path. Consider the following topology: A---B---C---D \ / E---F---G / \ H---I---J---K The working LSPs [A,B,C,D] and [H,I,J,K] could be protected by [A,E,F,G,D] and [H,E,F,G,K], respectively. In order to achieve resource merging during the signaling of these recovery LSPs (i.e. resource sharing), the LSPs must have the same Session Ids, but the Session Id includes the target (egress) IP address. These addresses are not the same in this example. Resource sharing along E, F, G can only be achieved if the nodes E, F and G recognize that the LSP Type setting of the secondary LSPs is for protection (see PROTECTION object, Section 14) and acts accordingly. In this case, the protecting LSPs are not merged (which is useful since the paths diverge at G), but the resources can be shared. When a failure is detected on one of the working LSPs (say at B), the error is propagated and/or notified to the ingress node (A), which activates the protecting LSP (see Section 8). At this point, it is important that a failure on the other LSP (say at J) does not cause the other ingress (H) to send the data down the protecting LSP since the resources are already in use. This can be achieved by node E using the following procedure. When the capacity is first reserved for the protecting LSP, E should verify that the LSPs being protected ([A,B,C,D] and [H,I,J,K], respectively) do not share any common resources. Then, when a failure occurs (say at B) and the protecting LSP [A,E,F,G,D] is activated, E should notify H that the resources for the protecting LSP [H,E,F,G,K] are no longer available. The following sub-sections details how shared mesh restoration can be implemented in an interoperable fashion using GMPLS RSVP-TE extensions (see [RFC-3473]). This includes: J.P.Lang et al. - Internet Draft û Expires November 2003 15 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 (1) the ability to identify a "secondary protecting LSP" (hereby called the "secondary LSP") used to recover another primary working LSP (hereby called the "protected LSP") (2) the ability to associate the secondary LSP with the protected LSP (3) the capability to include information about the resources used by the protected LSP while instantiating the secondary LSP. (4) the capability to instantiate during the provisioning phase several secondary LSPs in an efficient manner. (5) the capability to activate a secondary LSP after failure occurrence. In the following subsections, these features are described in detail. 10.1. Identifiers Since both LSPs (i.e. the primary working and the secondary protecting LSPs) correspond to the same session, the SESSION object MUST be the same for both LSPs. The LSP ID, however, MUST be different to distinguish between the two LSPs. 10.2 Signaling Primary LSPs A new PROTECTION object is included in the Path message during signaling of the primary working LSP. The PROTECTION object carries the desired end-to-end LSP Protection Type (in this case, "1:1 Re- routing without Extra-Traffic") as well as the LSP ID of the associated protecting LSP. This LSP Protection Type value is applicable to both uni- and bi-directional LSPs. Primary working LSPs are signaled by setting the both S bit and the P bit of the PROTECTION object to 0. 10.3 Signaling Secondary LSPs The new PROTECTION object carried in the Path message includes the desired end-to-end LSP Protection Type (in this case, "1:1 Re- routing without Extra-Traffic") as well as the LSP ID of the associated primary protected LSP, which MUST be known before signaling of the secondary LSP. This LSP Protection Type value is applicable to both uni- and bi-directional LSPs. Secondary LSPs are signaled by setting in this object the S bit to 1 and the P bit to 1. Moreover, the Path message used to instantiate the secondary LSP MUST include at least one PRIMARY PATH ROUTE object (see Section 15) that enables distinguishing shared mesh restoration at each intermediate node along the secondary path. Secondary LSPs are signaled using the S bit of the new PROTECTION object that is carried in the Path message. If set, the resources for the secondary LSP SHOULD be (pre-)reserved, but not committed at J.P.Lang et al. - Internet Draft û Expires November 2003 16 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 the data plane level meaning that the internals of the switch need not be established until explicit action is taken to activate this secondary LSP. Activation of a secondary LSP is done using a Path refresh message with the S bit set to 0 in the PROTECTION object. At this point, the link and node resources must to be allocated for the LSP that becomes a primary working LSP (ready to carry normal traffic). Two cases have to be covered here (see also [GMPLS-ARCH]) since the secondary LSP can be setup with resource reservation but with or without label pre-selection (both allowing sharing of the recovery resources). In the former case (defined as the default), secondary LSP signaling does not necessitate any specific procedure compared to the one defined in [RFC-3473]. However, in the latter case, label (and thus resource) re-allocation MAY occur during the secondary LSP activation. This means that during the LSP activation phase, labels MAY be re-assigned (with higher precedence over label assignment, see also [RFC-3471]). 11. (Full) LSP Re-routing LSP re-routing, on the other hand, switches normal traffic to an alternate LSP that is fully established after failure occurrence. The new (alternate) route is selected at the LSP head-end and may reuse intermediate nodes included in the original route; it may also include additional intermediate nodes. For strict-hop routing, TE requirements can be directly applied to the route computation, and the filed node or link can be avoided. However, if the failure occurred within a loose-routed hop, the head-end node may not have enough information to reroute the LSP around the failure. The alternate route may be either computed on demand (that is, when the failure occurs; this is referred to as full LSP re-routing) or pre-computed and stored for use when the failure is reported. The latter offers faster restoration time. There is, however, a risk that the alternate route will become out of date through other changes in the network - this can be mitigated to some extent by periodic recalculation of idle alternate routes. (Full) LSP re-routing will be initiated by the head-end node that has either detected the failure or received either a Notify message and/or a PathErr message indicating that a failure has occurred. The new LSP resources can be established using the make-before-break mechanism, where the new LSP is setup before the old LSP is torn down. This is done by using the mechanisms of the SESSION object and the Shared-Explicit (SE) reservation style (see [RFC-3209]). Both the new and old LSPs can share resources at common nodes. Note that the make-before-break mechanism is not used to avoid disruption to the normal traffic flow (the latter has already been broken by the failure that is being repaired). However, it is J.P.Lang et al. - Internet Draft û Expires November 2003 17 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 valuable to retain the resources allocated on the original LSP that will be re-used by the new alternate LSP. 11.1 Identifiers The Tunnel End Point Address, Tunnel Id, Extended Tunnel Id, Tunnel Sender Address and LSP Id are all used to uniquely identify both the old and new LSPs. The new (alternate) LSP is setup before the old LSP is torn down using Shared-Explicit (SE) reservation style. This ensures that the new LSP is established without double counting resource requirements along common segments. 11.2 Signalling Re-routable LSPs A new PROTECTION object is included in the Path message during signaling of dynamically re-routable LSPs, with the end-to-end LSP Protection Type value set to "Full Re-routing". These LSPs that can be either uni- or bi-directional are signaled by setting in this object the S bit to 0, the P bit to 0 and the Associated LSP ID to 0. Any specific action to be taken during the provisioning phase is up the end-node local policy. Note: when the end-to-end LSP Protection Type is set to "Unprotected", both S and P bit MUST be set to 0 and the LSP MUST NOT be re-routed at the head-end node after failure occurrence. The Associated LSP_ID value MUST be set to 0. 12. Reversion Reversion refers to a recovery switching operation, where the normal traffic returns to (or remains on) the working LSP when it has recovered from the failure. Reversion implies that resources remains allocated to the LSP that was originally routed over it even after a failure. It is important to have mechanisms that allow reversion to be performed with minimal service disruption and reconfiguration. For "1+1 bi-directional" and "1:1 with Extra-traffic" protection, reversion to the recovered LSP simply occurs by clearing its A bit in the ADMIN_STATUS object and applying the reverse 1-phase APS switchover request/response (or 2-phase APS) described in Section 6.2 (or Section 7.2, respectively). For "Re-routing without Extra-traffic" reversion implies that the formerly working LSP has not been torn down by the head-end upon PathErr message reception (i.e. the head-end node kept refreshing the working LSP under failure condition by setting A bit in the ADMIN STATUS object). This ensures that the same resources are retrieved after reversion switching. Re-activation is performed by clearing the A bit for the recovered working primary LSP and then set the S bit to 1 in the PROTECTION object sent over the protecting path. J.P.Lang et al. - Internet Draft û Expires November 2003 18 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 13. External Commands This section specifies the control plane behavior when using several external commands (see [TERM]), typically issued by an operator through the Network Management System (NMS)/Element Management System (EMS), which can be used to influence or command the recovery operations. Other specific commands may complete the below list. A. Lockout of recovery LSP: The Administratively Down bit (A bit) of the ADMIN_STATUS object is used following the rules defined in Section 8 of [RFC-3471] and Section 7 of [RFC-3473]. The A bit must be set together with the Reflect (R) bit set in the ADMIN_STATUS object. Its usage forces the recovery LSP to be temporarily unavailable to transport traffic (either normal or extra traffic). Unlock is performed by clearing the A bit. B. Lockout of normal traffic: The A bit usage forces the recovery LSP to be temporarily unavailable to transport normal traffic. The A bit must be set together with the Reflect (R) bit set in the ADMIN_STATUS object. Unlock is performed by clearing the A bit. C. Forced switch for normal traffic: Recovery signaling is initiated externally that switches normal traffic to the recovery LSP following the procedure defined in Section 7. D. Manual switch for normal traffic: Recovery signaling operation is initiated externally that switches normal traffic to the recovery LSP following the procedure defined in Section 7. This, unless a fault condition exists on other LSPs/spans (including the recovery LSP) or an equal or higher priority switch command is in effect. E. Manual switch for recovery LSP: Recovery signaling operation is initiated externally that switches normal traffic to the working LSP following the procedure defined in Section 12. This, unless a fault condition exists on the working LSP or an equal or higher priority switch command is in effect. 14. PROTECTION Object In this section, we describe the extensions to the PROTECTION object to broaden its applicability to end-to-end LSP recovery. In addition to modifications to the format of the PROTECTION object, we extend J.P.Lang et al. - Internet Draft û Expires November 2003 19 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 its use so that the object can be included in the Notify message to act a switchover request for 1+1 bi-directional and 1:1 protection. The format of the PROTECTION Object (Class-Num = 37, C-Type = TBA by IANA) is as follows: 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(37) | C-Type (TBA) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |S|P|N| Reserved | LSP Flags | Reserved | Link Flags| +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Associated LSP ID | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Secondary (S): 1 bit When set to 1, this bit indicates that the requested LSP is a secondary LSP. When set to 0 (default), it indicates that the requested LSP is a primary LSP. Protecting (P): 1 bit When set to 1, this bit indicates that the requested LSP is a protecting LSP. When set to 0 (default), it indicates that the requested LSP is a working LSP. The combination, S set to 1 with P set to 0 is not valid. Notification (N): 1 bit When set to 1, this bit indicates that the control plane message exchange is only used for notification during protection switching. When set to 0 (default), it indicates that the control plane message exchanges are used for protection switching purposes. The N bit is only applicable when the LSP Flag is set 0x10, 0x08 or 0x04 and MUST be set to 0 in any other case. Reserved: 7 bits This field is reserved. It MUST be set to zero on transmission and MUST be ignored on receipt. These bits SHOULD be pass through unmodified by transit nodes. LSP (Protection Type) Flags: 6 bits Indicates the desired end-to-end LSP recovery type. A value of 0 implies that the LSP is "Unprotected". Only one value SHOULD be set at a time. The following values are defined. All other values are reserved. J.P.Lang et al. - Internet Draft û Expires November 2003 20 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 0x00 Unprotected 0x01 (Full) Re-routing 0x02 1:1 Re-routing without Extra-Traffic 0x04 1:1 Protection with Extra-Traffic 0x08 1+1 Unidirectional Protection 0x10 1+1 Bi-directional Protection Reserved: 10 bits This field is reserved. It MUST be set to zero on transmission and MUST be ignored on receipt. These bits SHOULD be pass through unmodified by transit nodes. Link Flags: 6 bits Indicates the desired link protection type (see [RFC-3471]). Associated LSP ID: 16 bits Identifies the LSP protected by this LSP or the LSP protecting this LSP. If unknown, this value is set to 0 (default). Also, the value of the Associated LSP ID MAY change during the lifetime of the LSP. Reserved: 16 bits This field is reserved. It MUST be set to zero on transmission and MUST be ignored on receipt. These bits SHOULD be pass through unmodified by transit nodes. Intermediate nodes processing a Path message containing a PRIMARY PATH ROUTE object (see Section 15) and a PROTECTION object with the LSP Protection Type "0x02" value set MUST verify that the requested LSP Protection Type can be satisfied by the outgoing interface. If it cannot, the node MUST generate a PathErr message, with a "Routing problem/Unsupported LSP Protection" indication. If due to a resource unavailability on the outgoing interface, an intermediate node MUST return a PathErr with the "Routing Problem/LSP Admission Failure" error code. Intermediate and Egress nodes processing a Path message containing the PROTECTION object MUST verify that the requested LSP Protection Type can be satisfied by the incoming interface. If it cannot, the node MUST generate a PathErr message, with the "Routing problem/ Unsupported LSP Protection" error code. 15. PRIMARY PATH ROUTE Object The PRIMARY PATH ROUTE object (PPRO) is defined to inform nodes along the path of a secondary protecting LSP about which resources (link/nodes) are being used by the associated primary protected LSP J.P.Lang et al. - Internet Draft û Expires November 2003 21 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 (as specified by the Associated LSP ID field). This object MUST be if and only if the LSP Protection Type value is set to "0x02". This memo does not assume any other usage for this object. PRIMARY PATH ROUTE objects carry information extracted from the EXPLICIT ROUTE object and/or the RECORD ROUTE object of the primary working LSPs they protect. Selection of the PPRO content is up to local policy of the head-end LSR that initiates the request. Therefore, the information included in these objects MAY be used as policy-based admission control to ensure that secondary protecting LSPs that are sharing resources have (link/node/SRLG) disjoint paths for their associated primary LSPs. 15.1. Definition The primary path route is specified via the PRIMARY_PATH_ROUTE object (PPRO). The Primary Path Route Class Number is TBA by IANA. Currently one C-Type (Class-Type) is defined, Type 1 Primary Path Route. The PRIMARY_PATH_ROUTE object has the following format: Class-Num = TBA by IANA, C-Type = 1 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | // (Subobjects) // | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ The contents of a PRIMARY_PATH_ROUTE object are a series of variable-length data items called subobjects. The subobjects are identical to those that can constitute an EXPLICIT ROUTE object as defined in [RFC-3209], [RFC-3473] and [RFC-3477]. To signal a secondary protecting LSP, the Path message MUST include at least one or MAY include multiple PRIMARY_PATH_ROUTE objects, where each object is meaningful. The latter is useful when a given secondary protecting LSP must be link/node/SRLG disjoint from more than one primary LSP (i.e. is protecting more than one primary LSP). 15.2 Applicability The PRIMARY_PATH_ROUTE object MUST only be used when all GMPLS nodes along the path support the PRIMARY_PATH_ROUTE object and secondary protecting LSPs are requested. The PRIMARY_PATH_ROUTE object is assigned a class value of the form 0bbbbbbb. Receiving GMPLS nodes along the path that do not support this object MUST return a PathErr message with the "Unknown Object Class" error code. J.P.Lang et al. - Internet Draft û Expires November 2003 22 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 Also, the following restrictions MUST be applied with respect to the PPRO usage: - PPROs MUST only be sent over secondary protecting LSPs (S bit = 1 and P bit = 1) and when the LSP Protection Type value is set to "0x02" in the PROTECTION object (see Section 15.) - Crossed exchanges of PPROs over primary LSPs are forbidden (i.e. their usage is restricted to a single set of protected LSPs). If a PPRO is received with the S bit set to 0 in the PROTECTION object, the receiving node MUST return a PathErr with the "Routing Problem/PRIMARY PATH_ROUTE object not applicable" error code. - PPRO's content MUST NOT include subobjects coming from other PPROs. In particular, received PPROs MUST NOT be re-used to establish other working or protecting LSPs. 15.3 Subobjects The PRIMAY_PATH_ROUTE object is defined as a list of variable-length data items called subobjects. PPR subobjects are derived from the subobjects of the EXPLICIT ROUTE and/or RECORD ROUTE object of the primary working LSP(s). Each PPR subobject has its own length field. The length contains the total length of the subobject in bytes, including the Type and Length fields. The length MUST always be a multiple of 4, and at least 4. The following subobjects are currently defined for the PRIMARY PATH ROUTE object: - Sub-Type 1: IPv4 Address (see [RFC 3209]) - Sub-Type 2: IPv6 Address (see [RFC 3209]) - Sub-Type 3: Label (see [RFC-3473]) - Sub-Type 4: Unnumbered Interface (see [RFC-3477]) An empty PPRO with no subobjects is considered as illegal. If there is no first subobject, the corresponding Path message is also in error and the receiving node SHOULD return a PathErr with the "Routing Problem/Bad PRIMARY PATH_ROUTE object" error code. Note: SRLG identifier values can be derived from the local IGP-TE database using the Type 1, 2 or 4 subobjects listed here above as pointers to the corresponding TE Link Id. 16. Application Examples This section illustrates the use of the above-defined objects with respect to each of the recovery mechanisms considered in this memo. 16.1 1+1 Bi-directional Protection J.P.Lang et al. - Internet Draft û Expires November 2003 23 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 The protected LSP is signaled with both S bit and P bit set to 0. The protecting LSP is signaled with the S bit to 0 and P bit set to 1. LSP Flag is set to 0x10 (for both LSP setup). Associated LSP_IDs point the one to each other. 16.2 1+1 Unidirectional Protection The protected LSP is signaled with both S bit and P bit set to 0. The protecting LSP is signaled with S bit set to 0 and P bit set to 1. LSP Flag is set to 0x08 (for both LSP setup). Associated LSP_IDs point the one to each other. 16.3 1:1 Protection with Extra-Traffic (Path and bandwidth protection) The protected LSP is signaled with both S bit and P bit set to 0. LSP Flag is set to 0x04 (during LSP setup). Associated LSP ID points to the protecting LSP ID. The protecting LSP (carrying extra-traffic) is signaled with S bit set to 0 and P bits set to 1. LSP Flag is set to 0x04 (during LSP setup). Associated LSP ID points to the protected LSP ID. 16.4 1:1 Re-Routing without Extra-Traffic (Path protection only) The protected LSP is signaled with both S bit and P bit set to 0. LSP Flag is set to 0x02 (during LSP setup). Associated LSP ID points to the protecting LSP ID. The protecting LSP is signaled with both S bit and P bit set to 1. LSP Flag is set to 0x02 (during LSP setup). Associated LSP ID points to the protected LSP ID. 16.5 Shared Mesh Each protected LSP is setup with both S and P bits set to 0. LSP Flag is set to 0x02 (during LSP setup). Each Associated LSP ID points to the single protecting LSP ID. The single protecting LSP is setup with S bit set to 1 and P bits set to 1. LSP Flag is set to 0x02 (during LSP setup). Associated LSP ID MUST be set either to the protected LSP (single protected LSP) or to 0 (multiple Protected LSPs). In addition, the protecting LSP path message MUST carry at least PPRO object, typically one for each protected LSP. 16.6 Full Re-routing Each re-routable LSP is setup with both S and P bits set to 0. LSP Flag is set to 0x01 (during LSP setup). Associated LSP ID MUST be set to 0. J.P.Lang et al. - Internet Draft û Expires November 2003 24 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 17. Security Considerations This document does not introduce or imply any specific security consideration. 18. Acknowledgments The authors would like to thank John Drake for his active collaboration and Adrian Farrel for his contribution to this document (in particular to the Section 11). Many thanks also to Bart Rousseau (for its editorial revision) and Stefaan De_Cnodder. 19. IANA Considerations IANA assigns values to RSVP protocol parameters. Within the current document a PROTECTION object (new C-Type) and a PRIMARY PATH ROUTE object are defined. One RSVP Class Number (Class-Num) and two Class Types (C-Types) values have to be defined by IANA in registry: http://www.iana.org/assignments/rsvp-parameters - PROTECTION object: Class-Num = 37, C-Type = 2 (suggested) - PRIMARY PATH ROUTE object: Class-Num = 23 (suggested), C-Type = 1 (suggested) - Error codes: o "Routing Problem/Unsupported LSP Protection" (value = TBA) o "Routing Problem/LSP Admission Failure" (value = TBA) o "Routing Problem/Bad PRIMARY PATH_ROUTE object" (value = TBA) o "Routing Problem/PRIMARY PATH_ROUTE object not applicable" 20. Intellectual Property Considerations This section is taken from Section 10.4 of [RFC2026]. The IETF takes no position regarding the validity or scope of any intellectual property or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; neither does it represent that it has made any effort to identify any such rights. Information on the IETF's procedures with respect to rights in standards-track and standards-related documentation can be found in BCP-11. Copies of claims of rights made available for publication and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementors or users of this specification can be obtained from the IETF Secretariat. J.P.Lang et al. - Internet Draft û Expires November 2003 25 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights, which may cover technology that may be required to practice this standard. Please address the information to the IETF Executive Director. 21. References 21.1 Normative References [FUNCT] J.P.Lang and B.Rajagopalan (Editors), "Generalized MPLS Recovery Functional Specification," Internet Draft, Work in Progress, draft-ietf-ccamp-gmpls-recovery- functional-00.txt, January 2002. [GMPLS-ARCH] E.Mannie (Editor), "Generalized MPLS Architecture", Internet Draft, Work in progress, draft-ietf-ccamp- gmpls-architecture-06.txt, April 2003. [GMPLS-RTG] K.Kompella (Editor), "Routing Extensions in Support of Generalized MPLS," Internet Draft, Work in Progress, draft-ietf-ccamp-gmpls-routing-05.txt, August 2002. [LMP] J.Lang (Editor), "Link Management Protocol (LMP) v1.0," Internet Draft, Work in progress, draft-ietf-ccamp-lmp- 08, March 2003. [RFC-2026] S.Bradner, "The Internet Standards Process -- Revision 3," BCP 9, RFC 2026, October 1996. [RFC-2119] S.Bradner, "Key words for use in RFCs to Indicate Requirement Levels," BCP 14, RFC 2119, March 1997. [RFC-2961] L.Berger et al., "RSVP Refresh Overhead Reduction Extensions," RFC 2961, April 2001. [RFC-3209] D.Awduche et al., "RSVP-TE: Extensions to RSVP for LSP Tunnels," RFC 3209, December 2001. [RFC-3471] L.Berger, (Editor) et al., "Generalized MPLS û Signaling Functional Description," RFC 3471, February 2003. [RFC-3473] L.Berger (Editor) et al., "Generalized MPLS Signaling û RSVP-TE Extensions," RFC 3473, February 2003. [RFC-3477] K.Kompella, and Y.Rekhter, "Signalling Unnumbered Links in Resource Reservation Protocol - Traffic Engineering (RSVP-TE)," RFC 3477, January 2003. J.P.Lang et al. - Internet Draft û Expires November 2003 26 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 [TERM] E.Mannie and D.Papadimitriou (Editors), "Recovery (Protection and Restoration) Terminology for GMPLS," Internet Draft, Work in progress, draft-ietf-ccamp- gmpls-recovery-terminology-02.txt, May 2003. 21.2 Informative References [CCAMP-LI] G.Li et al. "RSVP-TE Extensions for Shared-Mesh Restoration in Transport Networks," Internet Draft, Work in progress, draft-li-shared-mesh-restoration- 01.txt, November 2001. 22. Author's Addresses Jonathan Lang (Rincon Networks) E-mail: jplang@ieee.org Yakov Rekhter (Juniper) 1194 N. Mathilda Avenue Sunnyvale, CA 94089, USA E-mail: yakov@juniper.net J.P.Lang et al. - Internet Draft û Expires November 2003 27 draft-lang-ccamp-gmpls-recovery-e2e-signaling-01.txt May 2003 Full Copyright Statement "Copyright (C) The Internet Society (date). All Rights Reserved. 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