One document matched: draft-ietf-mpls-p2mp-te-bypass-02.txt

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Network Working Group                                 J.L. Le Roux (Ed.) 
Internet Draft                                            France Telecom 
Category: Standard Track                 
Expires: August 2008                                         R. Aggarwal  
                                                        Juniper Networks 
                                                                         
                                                            J.P. Vasseur 
                                                     Cisco Systems, Inc. 
                                                                         
                                                            M. Vigoureux 
                                                          Alcatel-Lucent 
                                                                        
                                                                         
                                                              March 2008 
 
 
            P2MP MPLS-TE Fast Reroute with P2MP Bypass Tunnels 
 
                 draft-ietf-mpls-p2mp-te-bypass-02.txt 
 
 
Status of this Memo 
 
   By submitting this Internet-Draft, each author represents that any 
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Abstract 
    
   This document defines procedures for fast reroute protection of  
   Point-To-MultiPoint (P2MP) Traffic Engineering Label Switched Paths  
   (TE-LSP) in  MultiProtocol Label Switching (MPLS) networks, based  
   upon Point-To-MultiPoint Bypass Tunnels. The motivation for using   
   P2MP Bypass Tunnels is to avoid potentially expensive data   
   duplication along the backup path that could occur if Point-To-Point  
   Bypass Tunnels were used, i.e., to optimize the bandwidth usage,  
   during fast reroute protection of a link or a node. During link or  
   node failure the traffic carried onto a protected P2MP TE-LSP is  
   tunnelled within one or several P2MP Bypass Tunnels towards a set of  
   Merge Points. To avoid data duplication, backup labels (i.e., inner  
   labels) are assigned by the Point of Local Repair (PLR) according to      
   the RSVP-TE upstream label assignment procedure. 
 
 
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 RFC-2119. 
 
 
Table of Contents 
    
   1.      Terminology.................................................3 
   2.      Introduction................................................3 
   3.      Solution overview...........................................4 
   4.      PLR procedures..............................................6 
   4.1.    Before failure..............................................6 
   4.1.1.  P2MP Bypass Tunnel(s) Selection.............................6 
   4.1.2.  P2MP Backup LSP Signaling over a P2MP Bypass Tunnel.........7 
   4.2.    During failure..............................................8 
   4.3.    After failure...............................................8 
   5.      MP Procedures...............................................9 
   6.      Combination of P2P and P2MP Bypass tunnels..................9 
   7.      Partial Protection.........................................10 
   8.      Location of the PLR........................................11 
   9.      Security Considerations....................................11 
   10.     IANA Considerations........................................11 
   10.1.   LSP Attributes Flags.......................................11 
   11.     Acknowledgments............................................11 
   12.     References.................................................11 
   12.1.   Normative references.......................................11 
   12.2.   Informational references...................................12 
   13.     Authors' Addresses:........................................12 
   14.     Intellectual Property Statement............................13 
    
    
    
 
 
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1. Terminology 
 
   This document uses terminologies defined in [RFC3031], [RFC3209], 
   [RFC4090] and [RFC4461]. It defines the following new terms: 
 
   P2MP Bypass Tunnel: Point-to-Multipoint Bypass Tunnel. A P2MP TE- 
   LSP that is used to protect a set of P2MP TE-LSPs traversing a    
   common facility (link or node).  
    
   P2MP Facility Backup: A local repair method in which a P2MP Bypass    
   Tunnel is used to protect one or more P2MP TE-LSPs that traverse the 
   Point of Local Repair (P2MP Bypass Ingress) and the resource being 
   protected.  
 
   Backup P2MP LSP: The LSP that is used to backup up one of the    
   many protected P2MP LSPs in P2MP Facility Backup. 
    
   Backup label: Label of a backup P2MP LSP. 
    
   Backup S2L sub-LSP: A S2L sub-LSP of a backup P2MP LSP. 
    
   PLR: Point of Local Repair: Head-end LSR of the bypass tunnel 
    
   MP: Merge Point: LSR where a primary LSP and its backup LSP merge. 
 
                        . 
2. Introduction 
    
   [RFC4090] defines Fast ReRoute (FRR) extensions to RSVP-TE [RFC3209] 
   for local protection of Point-To-Point (P2P) Traffic Engineered Label 
   Switched Paths (TE LSP) in MultiProtocol Label Switching (MPLS) 
   networks. Two techniques are defined: the one-to-one backup method, 
   which creates a detour LSP for each protected LSP at each point of 
   local repair (PLR), and the facility backup method, which creates a 
   bypass tunnel that can be used to protect a set of TE LSPs by taking 
   advantage of MPLS label stacking. 
    
   [RFC4875] defines extensions to RSVP-TE for setting up Point-To- 
   Multipoint (P2MP) TE LSPs. It specifies extensions to one-to-one and  
   facility backup Fast Reroute procedures defined in [RFC4090] so as to  
   support fast reroute protection of P2MP TE LSPs.  
   The facility backup solution defined in [RFC4875] only relies on P2P 
   Bypass Tunnels for link and node protection. This faces the following 
   limitations:  
    
        - The protection of a downstream link of a P2MP TE LSP on a  
        branch LSR may require a P2P Bypass LSP that uses another 
        downstream link of the P2MP LSP, and this leads to twice the 
        traffic on that link during failure, which is inefficient. 
        Finding a bypass path that avoids all downstream links on the 
        P2MP LSP would be a solution but this is often not achievable in 
        lowly meshed topologies. 
 
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        - The protection of a P2MP TE LSP against node failures  
        requires, when the protected node is a Branch LSR, a set of P2P 
        Next-Next-Hop (NNHOP) Bypass Tunnels toward all LSRs downstream 
        to the  protected node. During failure the PLR has to replicate 
        traffic on each P2P NNHOP Bypass Tunnel. If there are K next-
        next-hops, this may lead to K times the traffic on some links,  
        which is not acceptable.  
         
        - Similarly the protection of a P2MP TE LSP against the failure  
        of a LAN interface that connects a branch LSR and a set of K  
        downstream LSRs requires one P2P Bypass Tunnel per downstream  
        LSR, which may lead to K times the traffic on some links during  
        failure. 
         
   To overcome these limitations it is highly desirable to define 
   extensions to the fast reroute facility backup solution, so as to 
   support P2MP Bypass Tunnels. This retains the scalability advantages 
   of MPLS label stacking and avoids sending multiple copies of a packet 
   on some links during failure. 
 
   This draft specifies extensions to the Fast ReRoute (FRR) procedures 
   defined in [RFC4090] and [RFC4875] to support local repair of P2MP TE 
   LSP with P2MP Bypass Tunnels.  
 
   Procedures defined in [RFC3209], [RFC4090] and [RFC4875] MUST be 
   followed unless specified below. 
 
3. Solution overview 
    
   The P2MP Facility Backup method defined in this document relies on 
   the use of P2MP Bypass Tunnels. Similarly to the P2P case, the same 
   P2MP Bypass Tunnel can be used to protect a set of P2MP TE LSPs, by 
   taking advantage of MPLS label stacking.  
 
   A P2MP Bypass Tunnel can be used to protect a P2MP TE-LSP against 
   downstream link or node failures.  
    
   There are various options for the protection of a downstream link or 
   node of a P2MP TE-LSP: 
    
        - Option 1: Rely on a single P2MP Bypass Tunnel whose set of 
           leaf LSRs exactly matches the set of Merge Points (MP). Merge 
           points are transit or egress LSRs on the protected P2MP LSP 
           downstream to the PLR or downstream to the protected element 
           (link or node). 
        - Option 2: Rely on a single P2MP Bypass Tunnel whose set of 
           leaf LSRs is a superset of the set of MPs. Leaf LSRs which 
           are not MP have to drop the traffic. 
        - Option 3: Rely on a combination of P2MP Bypass LSPs whose 
           leaf LSRs include a subset of the set of MPs but their 
 
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           combination encompass all MPs (and this combination may be a 
           superset of the set of MPs).  
         
    
   These three options differ in terms of bandwidth optimization and 
   control plane state minimization. Option 1 increases the number of 
   states compared to option 2, and, in some cases, to option 3(it 
   implies more P2MP Bypass LSPs), but is less expensive in terms of 
   bandwidth (traffic only sent to MPs). With point-to-multipoint 
   hierarchy there is always a tension between minimizing the amount of 
   control plane state and minimizing bandwidth consumption. Choosing 
   one of these options is a decision local to the PLR. The choice 
   depends on the desired trade-off between control plane and data plane 
   optimization, and the operational complexity associated with the 
   different options.  
    
   When the P2MP Facility Backup method is used, during failure the PLR 
   MUST send data for each protected P2MP LSP into the set of one or 
   more P2MP Bypass Tunnels. Label stacking is used: the inner label is 
   the backup label for the backup P2MP LSP, that will be used on the MP 
   to forward traffic to the corresponding protected P2MP LSP, and the 
   outer label is the P2MP Bypass Tunnel label. 
 
   To avoid data replication at the PLR and to avoid traffic mis-routing 
   in Merge Points, the same backup label MUST be used for all S2L sub-
   LSPs of a given backup P2MP LSP, tunneled within the same P2MP Bypass 
   Tunnel. This backup label will indicate to the Merge Points that 
   packets received with that label should be switched along the 
   protected P2MP LSP.   
    
   For that purpose upstream label assignment procedures defined in 
   [MPLS-UPSTREAM] and RSVP-TE extensions for upstream label assignment 
   defined in [RSVP-UP] MUST be used. To signal a backup P2MP LSP, the 
   same backup label, is distributed by the PLR to all MPs belonging to 
   a same P2MP Bypass Tunnel, in the context of this P2MP Bypass Tunnel.  
   This requires the backup P2MP LSP to be signaled prior to the failure  
 
   At the MP, backup S2L sub-LSPs (i.e., S2L sub-LSPs of the Backup P2MP 
   LSP) are merged with protected S2L sub-LSPs. A MP (i.e., the bypass 
   tunnel leaf LSRs), maintains a context specific Incoming Label Map 
   (ILM) for the P2MP Bypass Tunnel. This can be implemented by 
   maintaining a different context specific ILM for each LSR that is the 
   root of a P2MP Bypass Tunnel (per-neighbor), or by maintaining a 
   different context specific ILM for each P2MP Bypass Tunnel (per-
   tunnel). The context of an inner label (i.e., a backup label) is 
   determined by the underlying P2MP Bypass Tunnel on which it is 
   received (as described in section 5). This requires deactivating 
   Penultimate Hop Popping (PHP) on the P2MP Bypass Tunnel. A backup 
   label, in a given P2MP Bypass Tunnel specific ILM, is mapped to the 
   outgoing interface(s) and label(s) of the corresponding protected 
   P2MP LSP. 
    
 
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   The way in which the MP determines whether the PLR assigns upstream-
   assigned labels from a per-tunnel, or per-platform pool (a.k.a label 
   space) is outside the scope of this document. 
 
4. PLR procedures 
 
4.1. Before failure 
    
4.1.1. P2MP Bypass Tunnel(s) Selection 
 
   To protect a P2MP TE LSP against a downstream link or node failure, 
   using P2MP Facility Backup, a PLR has to select a set of one or more 
   P2MP Bypass Tunnel(s), denoted {B1.Bm}, as follows: 
         
        - The P2MP Bypass Tunnel(s) MUST NOT traverse the protected  
        link/node/SRLG. 
    
        - The set of leaf LSRs of P2MP Bypass Tunnels {B1.Bm}, denoted 
        {LSR1.LSRn} must include a set of Merge Points (MP), on the 
        protected P2MP LSP. These Merge Points are transit or egress 
        LSRs on the protected P2MP LSP downstream to the PLR or 
        downstream to the protected element (link or node). We will 
        denote this set of Merge Points as {MP1.MPq}. Note that the case 
        where some MPs are LSRs downstream to the PLR but not downstream 
        to the failed element allows avoiding sending twice the traffic 
        on downstream links during failure. 
         
        -The set of Merge Points {MP1.MPq} is such that in the event of  
        failure of the protected link or node, traffic received on the  
        protected P2MP LSP by the PLR, can be delivered to ALL the  
        leaf LSRs of the protected P2MP LSP downstream to the PLR, if it  
        is tunnelled to {MP1.MPq} over the set of one or more P2MP  
        Bypass Tunnel(s) {B1.Bm}. 
        Note: This condition, which provides full protection, does not 
        apply when partial protection mode is used (as described in 
        Section 7). 
    
    
   The PLR will assign backup labels to Merge Points {MP1.MPq} for the 
   backup P2MP LSP. The same label will be assigned to all Merge Points 
   belonging to the same P2MP Bypass Tunnel, as defined in [MPLS-
   UPSTREAM] and [RSVP-UP]. 
    
   A MP may actually be the leaf LSR of multiple P2MP Bypass Tunnels 
   used by the PLR to protect a given LSP (using Option 3 as described 
   in Section 3), but will be associated to only one P2MP Bypass Tunnel 
   (at a given time for a given protected P2MP LSP). That is, a PLR will 
   signal the P2MP Backup LSP to that MP, for a single P2MP Bypass 
   Tunnel context. When a MP is a leaf LSR of multiple P2MP Bypass 
   Tunnels, and if the PLR assigns the same backup label (i.e., inner 
   upstream-assigned label) for the backup P2MP LSP on several different 

 
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   P2MP Backup Tunnels, the MP MUST maintain a per-tunnel ILM (and not a 
   per-neighbor ILM) to perform contextual lookup of the backup label. 
    
 
   {LSR1.LSRn} may be a superset of {MP1.MPq}, that is some leaf LSRs of 
   a given P2MP Bypass Tunnel, noted {LSRx.LSRy}, may not belong to 
   {MP1.MPq}. The PLR will not distribute the backup label for the 
   backup P2MP LSP to these LSRs {LSRx.LSRy}.  
   However due to the nature of the P2MP Bypass Tunnel, during failure, 
   packets with the backup label will also be delivered onto the P2MP 
   Bypass Tunnel to {LSRx.LSRy}. {LSRx.LSRy} MUST discard these packets 
   based on the absence of an entry for this label in the context 
   specific ILM referred to that P2MP Bypass Tunnel. This requires that 
   {LSRx.LSRy} create a context specific ILM, per-tunnel or per-neighbor
   for that P2MP Bypass Tunnel label.   
 
   PHP MUST be deactivated on the P2MP Bypass Tunnel, in order to allow 
   MPs to determine the context for the backup labels assigned by the 
   PLR. Hence the P2MP Bypass Tunnel will be signaled with the "non PHP 
   behavior desired" bit set in the Attribute Flags TLV as specified in 
   [NO-PHP]. 
 
   Note that P2MP Bypass Tunnels may be signaled in advance, prior to 
   the establishment of any protected P2MP LSP, either automatically or 
   via configuration, or may be dynamically setup upon signaling of a 
   protected P2MP LSP. Such procedures rely on local implementation 
   issues and are beyond the scope of this document. 
 
    
4.1.2. P2MP Backup LSP Signaling over a P2MP Bypass Tunnel 
 
   The same backup label (i.e., the inner label) MUST be used for all 
   backup S2L sub-LSPs which are tunneled within the same P2MP Bypass 
   Tunnel, so as to avoid traffic replication at the PLR, and to avoid 
   traffic misrouting in the MPs. This label MUST be assigned by the PLR 
   using upstream label assignment procedures as specified in [MPLS-
   UPSTREAM] and [RSVP-UP]. 
 
   Backup P2MP LSPs MUST be signaled prior to the failure. To signal the 
   backup P2MP LSP, the PLR will send one or more Path messages, 
   referred to as a backup LSP's Path message, to each MP, as specified 
   in [RFC4875]. A backup LSP's Path message to a given MP comprises one 
   or more backup S2L sub-LSPs that transit through this MP.  
   A backup Path message MUST be sent to the MP using directed 
   signaling, i.e., it is addressed to the MP, without Router Alert 
   option. 
    
   As specified in [RFC4875] it is RECOMMENDED that the PLR use the 
   sender template specific method to identify a backup LSP's Path 
   message, that is, the PLR will set the source address in the sender 
   template to a local PLR address.  
    
 
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   The backup label MUST be assigned by the PLR, in the context of the 
   underlying P2MP Bypass Tunnel, following upstream label assignment 
   [MPLS-UPSTREAM] and P2MP RSVP-TE context identification procedures 
   defined in [RSVP-UP]. Hence, a backup LSP's Path message sent to a 
   given MP MUST include an Upstream Assigned Label object carrying the 
   value of the backup label. It MUST also include an RSVP-TE P2MP LSP 
   TLV within an IF_ID_RSVP_HOP object, that carries the session object 
   of the underlying P2MP Bypass Tunnel. This allows the MP to identify 
   the label space of the backup label assigned by the PLR. The same 
   backup label MUST be sent to all MPs belonging to a given P2MP Bypass 
   Tunnel. 
    
   Note that the PLR MUST continue to refresh Path messages for the 
   protected P2MP TE LSP along the nominal route. 
 
   The processing of backup S2L sub-LSP SEROs/SRROs MUST follow  
   backup LSP ERO/RRO processing described in [RFC4090]. 
    
    
4.2. During failure 
    
   When the PLR detects a link or/and node failure condition, it has to 
   reroute a protected P2MP LSP onto a set of one or more P2MP Bypass 
   Tunnels protecting the failed element, using as inner label(s) the 
   backup label(s) assigned for this P2MP LSP.  
    
   The PLR needs to localize the failed elements in order to activate 
   the P2MP Bypass Tunnel(s) protecting this element. Mechanisms through 
   which this location is retrieved are out of the scope of this 
   document. 
    
   Note that when some MPs are LSRs downstream to the PLR but not 
   downstream to the failed element, the PLR MUST stop sending traffic 
   directly within the protected P2MP TE LSP towards these MPs. This 
   allows avoiding sending twice the traffic on downstream links during 
   failure. 
 
   The processing of backup S2L sub-LSP SEROs/SRROs MUST follow  
   backup tunnel ERO/RRO processing described in [RFC4090].  
 
4.3. After failure  
    
   Reversion procedures for restoring the P2MP TE LSP to a full working 
   path after failure MUST follow procedures defined in section 6.5.2 of 
   [RFC4090], that is there are two basic strategies for restoring the 
   P2MP TE-LSP: The global revertive mode and the local revertive mode. 
    
    
 
 
 
 
 
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5. MP Procedures 
    
   A MP receives one or more Path messages for the protected P2MP TE LSP 
   and one or more Path messages for the backup P2MP LSP. 
    
   Note that, as specified in [RFC4090], the reception of a backup LSP's 
   Path message does not indicate that a failure has occurred or that 
   the incoming protected LSP will no longer be used. 
    
   A S2L sub-LSP is received within a Path message for the protected 
   P2MP LSP and within a Path message for the backup P2MP LSP. These two 
   Path messages are distinguished thanks to the sender-template 
   specific method. As specified in [RFC4090], each of these Path 
   messages will have a different sender address. The protected LSP can 
   be recognized because it will include the FAST_REROUTE object or have 
   the "local protection desired" flag set in the SESSION_ATTRIBUTE 
   object, or both. 
 
   A MP MUST maintain one context specific ILM table per PLR or per P2MP 
   Bypass Tunnel for which it is a leaf LSR.  
    
   A MP MUST install the upstream assigned label received in a backup 
   LSP's Path message (i.e., the backup label), within an ILM either 
   specific to the underlying P2MP Bypass Tunnel or specific to the PLR, 
   which is the ingress node of the underlying P2MP Bypass Tunnel. The 
   underlying P2MP bypass tunnel is identified by its session object, 
   carried within the IF_ID_RSVP_HOP object of the backup LSP's Path 
   message. An upstream assigned label for a backup P2MP LSP MUST be 
   mapped to the outgoing interface(s) and label(s) of the corresponding 
   protected P2MP LSP. 
    
   As specified in [RSVP-UP], the Resv message sent by a MP to the PLR, 
   does not carry any Label Object. 
 
   The processing of backup S2L sub-LSP SEROs/SRROs MUST follow  
   backup tunnel ERO/RRO processing described in [RFC4090]. 
 
6. Combination of P2P and P2MP Bypass tunnels 
    
   The P2MP Facility Backup method defined in this document and the P2P 
   Facility Backup method defined in [RFC4090] may be used in 
   conjunction. That is, a P2MP LSP may be protected on a PLR using a 
   combination of a set of P2P and P2MP Bypass Tunnels. 
    
   In this case S2L sub-LSPs protected by a P2P Bypass Tunnel are  
   signalled using procedures defined in [RFC4875] with the backup label  
   downstream assigned by the MP, while S2L sub-LSPs protected by a  
   P2MP Bypass Tunnel are signaled using procedures defined in this  
   document, with the backup label upstream assigned by the PLR.   
    
   This allows for backward compatibility with LSRs that do not support  
 
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   upstream assigned labels. A P2P Bypass Tunnel MUST be used to tunnel  
   traffic to a MP that do not support upstream assigned labels. 
    
    
7. Partial Protection 
    
   In some cases, in particular in some networks where bandwidth is a 
   scarce resource, the PLR may not be able to find a set of P2P and/or 
   P2MP Bypass Tunnels that cover all merge points. That is, only a 
   subset of merge points are covered, and upon failure, traffic will 
   not be delivered to all leaf LSRs downstream to the failed element. 
   Such a situation is referred to as partial protection as opposed to 
   full protection where all merge points are covered. 
    
   Hence, on a given PLR, a P2MP LSP may be fully, partially or non 
   protected. The default behavior on a PLR is that when a P2MP LSP 
   cannot be fully protected it is not protected at all. But the ingress 
   LSR may request 'P2MP Partial Protection' such that if a P2MP LSP 
   cannot be fully protected it is partially protected. 
    
   In order to request and record "P2MP Partial Protection" behavior, 
   this document defines a new bit in the Attributes Flags TLV of the  
   LSP_ATTRIBUTES object and the RRO Attributes sub-object defined in 
   [RFC4420]:  
        
         Bit Number 8 (TBD): P2MP Partial Protection 
 
 
   This bit SHOULD be set by the Ingress node in the Attributes Flags  
   TLV of the LSP_ATTRIBUTES object in the Path message for the LSP  
   for which P2MP Partial Protection is desired when full protection 
   cannot be provided. This bit MUST NOT be modified by any other nodes 
   along the LSP.  
 
   If a PLR supports the P2MP Partial Protection bit, and the bit is set 
   in a Path message, then it SHOULD setup a partial protection when a 
   full protection cannot be provided. In all other cases, the default 
   procedure applies, that is, the PLR MUST not setup any protection if 
   a full protection cannot be provided.  
    
   A PLR that recognizes the partial protection flag, but does not 
   support it, MUST ignore the request and apply default procedure. 
    
   When this bit is set in an RRO Attributes Subobject, this means that 
   the P2MP LSP is only partially protected on the node. In this case 
   the local protection available bit in the RRO flags MUST also be set. 
   A PLR that supports this flag MUST set it in the RRO Attributes 
   subobject, if it has setup a partial protection for a P2MP LSP. 
    
   The way in which a PLR chooses which set of MPs to target, when it 
   has to setup a partial protection, is out of the scope of this 
   document.  
 
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8. Location of the PLR 
    
   The PLR may be directly upstream to the protected link or node or may 
   also be two or more hops upstream. 
    
   In case the PLR is not directly upstream to the failure, rerouting 
   within the Bypass Tunnel(s) may be triggered by the following events: 
        -Failure of a BFD session between the PLR and the protected  
         Element. 
        -A PathErr message, that indicates the location of the failed  
         Element. 
 
 
9. Security Considerations 
    
   No new security issues are raised in this document. 
    
10. IANA Considerations 
    
10.1. LSP Attributes Flags 
 
   IANA has been asked to manage the space of flags in the Attributes 
   Flags TLV carried in the LSP_ATTRIBUTES object [RFC4420]. 
    
   This document defines a new flag as follows: 
    
      Bit Number:                       8 (suggested value) 
      Meaning:                          P2MP Partial Protection Desired 
      Used in Attributes Flags on Path: Yes 
      Used in Attributes Flags on Resv: No 
      Used in Attributes Flags on RRO:  Yes 
      Referenced Section of this Doc:   7 
    
11. Acknowledgments 
    
   We would like to thank Kireeti Kompella, Venu Hemige, Laurent 
   Ciavaglia, and Yannick Brehon, for the useful comments and 
   discussions. 
    
 
12. References 
    
    
12.1. Normative references 
    
   [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate  
   Requirement Levels", BCP 14, RFC 2119, March 1997.  
 
   [RFC3031] E. Rosen, A. Viswanathan, R. Callon, "MPLS Architecture", 

 
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   RFC 3031. 
      
   [RFC3209] D. Awduche et al., "RSVP-TE: Extensions to RSVP for LSP   
   Tunnels", RFC3209. 
 
   [RFC4461] S. Yasukawa et al., "Signaling Requirements for Point-to-  
   Multipoint Traffic-Engineered MPLS Label Switched Paths (LSPs)", 
   RFC4461. 
 
   [RFC4090] Pan, Swallow, Atlas, et al., "Fast Reroute Extensions to  
   RSVP-TE for LSP Tunnels", RFC4090. 
    
   [RFC4875] Aggarwal, Papadimitriou, Yasukawa et al. "Extensions to 
   RSVP-TE for Point to Multipoint TE LSPs", RFC4875, May 2007. 
    
   [MPLS-UPSTREAM] Aggarwal, Rekhter, Rosen, "MPLS Upstream Label  
   Assignment and Context Specific Label Space", draft-ietf-mpls-
   upstream-label, work in progress. 
 
   [RSVP-UP] Aggarwal, Le Roux, "MPLS Upstream Label Assignment for 
   RSVP-TE", draft-ietf-mpls-rsvp-upstream, work in progress. 
    
   [RFC4420] Farrel, A., Ed., et al."Encoding of Attributes for 
   Multiprotocol Label Switching (MPLS) Label Switched Path (LSP) 
   Establishment Using Resource ReserVation Protocol-Traffic Engineering 
   (RSVP-TE)", RFC 4420, February 2006. 
 
12.2. Informational references 
    
   [NO-PHP] Ali, Swallow, Aggarwal, "Non PHP Behavior and out-of-band 
   mapping for RSVP-TE LSPs", draft-ietf-mpls-rsvp-te-no-php-oob-
   mapping, work in progress 
     
 
 
13. Authors' Addresses:  
     
   Jean-Louis Le Roux  
   France Telecom  
   2, avenue Pierre-Marzin  
   22307 Lannion Cedex  
   FRANCE 
   Email: jeanlouis.leroux@orange-ftgroup.com 
     
   Rahul Aggarwal 
   Juniper Networks 
   1194 North Mathilda Ave. 
   Sunnyvale, CA 94089 
   USA 
   Email: rahul@juniper.net 
    
    
 
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   Jean-Philippe Vasseur  
   Cisco Systems, Inc.  
   1414 Massachusetts avenue  
   Boxborough , MA - 01719  
   USA  
   Email: jpv@cisco.com  
    
   M. Vigoureux 
   Alcatel-Lucent France 
   Route de Villejust 
   91620 Nozay 
   FRANCE 
   Email: martin.vigoureux@alcatel-lucent.fr 
 
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   Copyright (C) The IETF Trust (2008). This document is subject to the 
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