draft-ietf-bess-mvpn-fast-failover-02.txt   draft-ietf-bess-mvpn-fast-failover-03.txt 
Network Working Group T. Morin, Ed. Network Working Group T. Morin, Ed.
Internet-Draft Orange Internet-Draft Orange
Intended status: Standards Track R. Kebler, Ed. Intended status: Standards Track R. Kebler, Ed.
Expires: September 14, 2017 Juniper Networks Expires: November 5, 2018 Juniper Networks
March 13, 2017 G. Mirsky, Ed.
ZTE Corp.
May 4, 2018
Multicast VPN fast upstream failover Multicast VPN fast upstream failover
draft-ietf-bess-mvpn-fast-failover-02 draft-ietf-bess-mvpn-fast-failover-03
Abstract Abstract
This document defines multicast VPN extensions and procedures that This document defines multicast VPN extensions and procedures that
allow fast failover for upstream failures, by allowing downstream PEs allow fast failover for upstream failures, by allowing downstream PEs
to take into account the status of Provider-Tunnels (P-tunnels) when to take into account the status of Provider-Tunnels (P-tunnels) when
selecting the upstream PE for a VPN multicast flow, and extending BGP selecting the upstream PE for a VPN multicast flow, and extending BGP
MVPN routing so that a C-multicast route can be advertized toward a MVPN routing so that a C-multicast route can be advertised toward a
standby upstream PE. standby upstream PE.
Requirements Language Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
document are to be interpreted as described in RFC 2119 [RFC2119]. "OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 14, 2017. This Internet-Draft will expire on November 5, 2018.
Copyright Notice Copyright Notice
Copyright (c) 2017 IETF Trust and the persons identified as the Copyright (c) 2018 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. UMH Selection based on tunnel status . . . . . . . . . . . . 3 3. UMH Selection based on tunnel status . . . . . . . . . . . . 3
3.1. Determining the status of a tunnel . . . . . . . . . . . 4 3.1. Determining the status of a tunnel . . . . . . . . . . . 4
3.1.1. mVPN tunnel root tracking . . . . . . . . . . . . . . 5 3.1.1. mVPN tunnel root tracking . . . . . . . . . . . . . . 5
3.1.2. PE-P Upstream link status . . . . . . . . . . . . . . 5 3.1.2. PE-P Upstream link status . . . . . . . . . . . . . . 5
3.1.3. P2MP RSVP-TE tunnels . . . . . . . . . . . . . . . . 5 3.1.3. P2MP RSVP-TE tunnels . . . . . . . . . . . . . . . . 5
3.1.4. Leaf-initiated P-tunnels . . . . . . . . . . . . . . 6 3.1.4. Leaf-initiated P-tunnels . . . . . . . . . . . . . . 6
3.1.5. (S,G) counter information . . . . . . . . . . . . . . 6 3.1.5. ((S, G)) counter information . . . . . . . . . . . . 6
3.1.6. BFD Discriminator . . . . . . . . . . . . . . . . . . 6 3.1.6. BFD Discriminator . . . . . . . . . . . . . . . . . . 6
3.1.7. Per PE-CE link BFD Discriminator . . . . . . . . . . 8 3.1.7. Per PE-CE link BFD Discriminator . . . . . . . . . . 9
4. Standby C-multicast route . . . . . . . . . . . . . . . . . . 9 4. Standby C-multicast route . . . . . . . . . . . . . . . . . . 10
4.1. Downstream PE behavior . . . . . . . . . . . . . . . . . 10 4.1. Downstream PE behavior . . . . . . . . . . . . . . . . . 11
4.2. Upstream PE behavior . . . . . . . . . . . . . . . . . . 11 4.2. Upstream PE behavior . . . . . . . . . . . . . . . . . . 12
4.3. Reachability determination . . . . . . . . . . . . . . . 12 4.3. Reachability determination . . . . . . . . . . . . . . . 13
4.4. Inter-AS . . . . . . . . . . . . . . . . . . . . . . . . 12 4.4. Inter-AS . . . . . . . . . . . . . . . . . . . . . . . . 13
4.4.1. Inter-AS procedures for downstream PEs, ASBR fast 4.4.1. Inter-AS procedures for downstream PEs, ASBR fast
failover . . . . . . . . . . . . . . . . . . . . . . 13 failover . . . . . . . . . . . . . . . . . . . . . . 14
4.4.2. Inter-AS procedures for ASBRs . . . . . . . . . . . . 13 4.4.2. Inter-AS procedures for ASBRs . . . . . . . . . . . . 14
5. Hot leaf standby . . . . . . . . . . . . . . . . . . . . . . 13 5. Hot leaf standby . . . . . . . . . . . . . . . . . . . . . . 14
6. Duplicate packets . . . . . . . . . . . . . . . . . . . . . . 14 6. Duplicate packets . . . . . . . . . . . . . . . . . . . . . . 15
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
8. Security Considerations . . . . . . . . . . . . . . . . . . . 15 8. Security Considerations . . . . . . . . . . . . . . . . . . . 15
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 15 9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 16
10. Contributor Addresses . . . . . . . . . . . . . . . . . . . . 15 10. Contributor Addresses . . . . . . . . . . . . . . . . . . . . 16
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 17 11. References . . . . . . . . . . . . . . . . . . . . . . . . . 18
11.1. Normative References . . . . . . . . . . . . . . . . . . 17 11.1. Normative References . . . . . . . . . . . . . . . . . . 18
11.2. Informative References . . . . . . . . . . . . . . . . . 17 11.2. Informative References . . . . . . . . . . . . . . . . . 18
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 19
1. Introduction 1. Introduction
In the context of multicast in BGP/MPLS VPNs, it is desirable to In the context of multicast in BGP/MPLS VPNs, it is desirable to
provide mechanisms allowing fast recovery of connectivity on provide mechanisms allowing fast recovery of connectivity on
different types of failures. This document addresses failures of different types of failures. This document addresses failures of
elements in the provider network that are upstream of PEs connected elements in the provider network that are upstream of PEs connected
to VPN sites with receivers. to VPN sites with receivers.
Section 3 describes local procedures allowing an egress PE (a PE Section 3 describes local procedures allowing an egress PE (a PE
connected to a receiver site) to take into account the status of connected to a receiver site) to take into account the status of
P-Tunnels to determine the Upstream Multicast Hop (UMH) for a given P-tunnels to determine the Upstream Multicast Hop (UMH) for a given
(C-S, C-G). This method does not provide a "fast failover" solution (C-S, C-G). This method does not provide a "fast failover" solution
when used alone, but can be used with the following sections for a when used alone, but can be used with the following sections for a
"fast failover" solution. "fast failover" solution.
Section 4 describes protocol extensions that can speed up failover by Section 4 describes protocol extensions that can speed up failover by
not requiring any multicast VPN routing message exchange at recovery not requiring any multicast VPN routing message exchange at recovery
time. time.
Moreover, section 5 describes a "hot leaf standby" mechanism, that Moreover, section 5 describes a "hot leaf standby" mechanism, that
uses a combination of these two mechanisms. This approach has uses a combination of these two mechanisms. This approach has
skipping to change at page 3, line 42 skipping to change at page 3, line 48
Current multicast VPN specifications [RFC6513], section 5.1, describe Current multicast VPN specifications [RFC6513], section 5.1, describe
the procedures used by a multicast VPN downstream PE to determine the procedures used by a multicast VPN downstream PE to determine
what the upstream multicast hop (UMH) is for a given (C-S,C-G). what the upstream multicast hop (UMH) is for a given (C-S,C-G).
The procedure described here is an OPTIONAL procedure that consists The procedure described here is an OPTIONAL procedure that consists
of having a downstream PE take into account the status of P-tunnels of having a downstream PE take into account the status of P-tunnels
rooted at each possible upstream PEs, for including or not including rooted at each possible upstream PEs, for including or not including
each given PE in the list of candidate UMHs for a given (C-S,C-G) each given PE in the list of candidate UMHs for a given (C-S,C-G)
state. The result is that, if a P-tunnel is "down" (see state. The result is that, if a P-tunnel is "down" (see
Section 3.1), the PE that is the root of the P-Tunnel will not be Section 3.1), the PE that is the root of the P-tunnel will not be
considered for UMH selection, which will result in the downstream PE considered for UMH selection, which will result in the downstream PE
to failover to the upstream PE which is next in the list of to failover to the upstream PE which is next in the list of
candidates. candidates.
A downstream PE monitors the status of the tunnels of UMHs that are A downstream PE monitors the status of the tunnels of UMHs that are
ahead of the current one. Whenever the downstream PE determines that ahead of the current one. Whenever the downstream PE determines that
one of these tunnels is no longer "known to down", the PE selects the one of these tunnels is no longer "known to down", the PE selects the
UMH corresponding to that as the new UMH. UMH corresponding to that as the new UMH.
More precisely, UMH determination for a given (C-S,C-G) will consider More precisely, UMH determination for a given (C-S,C-G) will consider
the UMH candidates in the following order: the UMH candidates in the following order:
o first, the UMH candidates that either (a) advertise a PMSI bound o first, the UMH candidates that either (a) advertise a PMSI bound
to a tunnel, where the specified tunnel is not known to be down or to a tunnel, where the specified tunnel is not known to be down or
(b) do not advertise any x-PMSI applicable to the given (C-S,C-G) (b) do not advertise any x-PMSI applicable to the given (C-S,C-G)
but have associated a VRF Route Import BGP attribute to the but have associated a VRF Route Import BGP attribute to the
unicast VPN route for S (this is necessary to avoid incorrectly unicast VPN route for S (this is necessary to avoid incorrectly
invalidating an UMH PE that would use a policy where no I-PMSI is invalidating an UMH PE that would use a policy where no I-PMSI is
advertized for a given VRF and where only S-PMSI are used, the advertised for a given VRF and where only S-PMSI are used, the
S-PMSI advertisement being possibly done only after the upstream S-PMSI advertisement being possibly done only after the upstream
PE receives a C-multicast route for (C-S, C-G)/(C-*, C-G) to be PE receives a C-multicast route for (C-S, C-G)/(C-*, C-G) to be
carried over the advertized S-PMSI) carried over the advertised S-PMSI)
o second, the UMH candidates that advertise a PMSI bound to a tunnel o second, the UMH candidates that advertise a PMSI bound to a tunnel
that is "down" -- these will thus be used as a last resort to that is "down" -- these will thus be used as a last resort to
ensure a graceful fallback to the basic MVPN UMH selection ensure a graceful fallback to the basic MVPN UMH selection
procedures in the hypothetical case where a false negative would procedures in the hypothetical case where a false negative would
occur when determining the status of all tunnels occur when determining the status of all tunnels
For a given downstream PE and a given VRF, the P-tunnel corresponding For a given downstream PE and a given VRF, the P-tunnel corresponding
to a given upstream PE for a given (C-S,C-G) state is the S-PMSI to a given upstream PE for a given (C-S,C-G) state is the S-PMSI
tunnel advertized by that upstream PE for this (C-S,C-G) and imported tunnel advertised by that upstream PE for this (C-S,C-G) and imported
into that VRF, or if there isn't any such S-PMSI, the I-PMSI tunnel into that VRF, or if there isn't any such S-PMSI, the I-PMSI tunnel
advertized by that PE and imported into that VRF. advertised by that PE and imported into that VRF.
Note that this documents assumes that if a site of a given MVPN that Note that this document assumes that if a site of a given MVPN that
contains C-S is dual-homed to two PEs, then all the other sites of contains C-S is dual-homed to two PEs, then all the other sites of
that MVPN would have two unicast VPN routes (VPN-IPv4 or VPN-IPv6) that MVPN would have two unicast VPN routes (VPN-IPv4 or VPN-IPv6)
routes to C-S, each with its own RD. routes to C-S, each with its own RD.
3.1. Determining the status of a tunnel 3.1. Determining the status of a tunnel
Different factors can be considered to determine the "status" of a Different factors can be considered to determine the "status" of a
P-tunnel and are described in the following sub-sections. The P-tunnel and are described in the following sub-sections. The
procedure proposed here also allows that all downstream PEs don't procedure proposed here also allows that all downstream PEs don't
apply the same rules to define what the status of a P-tunnel is apply the same rules to define what the status of a P-tunnel is
skipping to change at page 5, line 15 skipping to change at page 5, line 19
Depending on the criteria used to determine the status of a P-tunnel, Depending on the criteria used to determine the status of a P-tunnel,
there may be an interaction with another resiliency mechanism used there may be an interaction with another resiliency mechanism used
for the P-tunnel itself, and the UMH update may happen immediately or for the P-tunnel itself, and the UMH update may happen immediately or
may need to be delayed. Each particular case is covered in each may need to be delayed. Each particular case is covered in each
separate sub-section below. separate sub-section below.
3.1.1. mVPN tunnel root tracking 3.1.1. mVPN tunnel root tracking
A condition to consider that the status of a P-tunnel is up is that A condition to consider that the status of a P-tunnel is up is that
the root of the tunnel, as determined in the PMSI tunnel attribute, the root of the tunnel, as determined in the PMSI tunnel attribute,
is reachable through unicast routing tables. In this case the is reachable through unicast routing tables. In this case, the
downstream PE can immediately update its UMH when the reachability downstream PE can immediately update its UMH when the reachability
condition changes. condition changes.
This is similar to BGP next-hop tracking for VPN routes, except that This is similar to BGP next-hop tracking for VPN routes, except that
the address considered is not the BGP next-hop address, but the root the address considered is not the BGP next-hop address, but the root
address in the PMSI tunnel attribute. address in the PMSI tunnel attribute.
If BGP next-hop tracking is done for VPN routes, and the root address If BGP next-hop tracking is done for VPN routes and the root address
of a given tunnel happens to be the same as the next-hop address in of a given tunnel happens to be the same as the next-hop address in
the BGP autodiscovery route advertising the tunnel, then this the BGP auto-discovery route advertising the tunnel, then this
mechanisms may be omitted for this tunnel, as it will not bring any mechanisms may be omitted for this tunnel, as it will not bring any
specific benefit. specific benefit.
3.1.2. PE-P Upstream link status 3.1.2. PE-P Upstream link status
A condition to consider a tunnel status as up can be that the last- A condition to consider a tunnel status as Up can be that the last-
hop link of the P-tunnel is up. hop link of the P-tunnel is up.
This method should not be used when there is a fast restoration This method should not be used when there is a fast restoration
mechanism (such as MPLS FRR [RFC4090]) in place for the link. mechanism (such as MPLS FRR [RFC4090]) in place for the link.
3.1.3. P2MP RSVP-TE tunnels 3.1.3. P2MP RSVP-TE tunnels
For P-Tunnels of type P2MP MPLS-TE, the status of the P-Tunnel is For P-tunnels of type P2MP MPLS-TE, the status of the P-tunnel is
considered up if one or more of the P2MP RSVP-TE LSPs, identified by considered up if one or more of the P2MP RSVP-TE LSPs, identified by
the P-Tunnel Attribute, are in up state. The determination of the P-tunnel Attribute, are in Up state. The determination of
whether a P2MP RSVP-TE LSP is in up state requires Path and Resv whether a P2MP RSVP-TE LSP is in Up state requires Path and Resv
state for the LSP and is based on procedures in [RFC4875]. In this state for the LSP and is based on procedures in [RFC4875]. In this
case the downstream PE can immediately update its UMH when the case, the downstream PE can immediately update its UMH when the
reachability condition changes. reachability condition changes.
When signaling state for a P2MP TE LSP is removed (e.g. if the When signaling state for a P2MP TE LSP is removed (e.g. if the
ingress of the P2MP TE LSP sends a PathTear message) or the P2MP TE ingress of the P2MP TE LSP sends a PathTear message) or the P2MP TE
LSP changes state from up to down as determined by procedures in LSP changes state from Up to Down as determined by procedures in
[RFC4875], the status of the corresponding P-Tunnel SHOULD be re- [RFC4875], the status of the corresponding P-tunnel SHOULD be re-
evaluated. If the P-Tunnel transitions from up to down state, the evaluated. If the P-tunnel transitions from up to Down state, the
upstream PE, that is the ingress of the P-Tunnel, SHOULD not be upstream PE, that is the ingress of the P-tunnel, SHOULD NOT be
considered a valid UMH. considered a valid UMH.
3.1.4. Leaf-initiated P-tunnels 3.1.4. Leaf-initiated P-tunnels
A PE can be removed from the UMH candidate list for a given (S,G) if A PE can be removed from the UMH candidate list for a given ((S, G))
the P-tunnel for this S,G (I or S , depending) is leaf triggered if the P-tunnel for this (S, G) (I or S , depending) is leaf
(PIM, mLDP), but for some reason internal to the protocol the triggered (PIM, mLDP), but for some reason internal to the protocol
upstream one-hop branch of the tunnel from P to PE cannot be built. the upstream one-hop branch of the tunnel from P to PE cannot be
In this case the downstream PE can immediately update its UMH when built. In this case, the downstream PE can immediately update its
the reachability condition changes. UMH when the reachability condition changes.
3.1.5. (S,G) counter information 3.1.5. ((S, G)) counter information
In cases, where the downstream node can be configured so that the In cases, where the downstream node can be configured so that the
maximum inter-packet time is known for all the multicast flows mapped maximum inter-packet time is known for all the multicast flows mapped
on a P-tunnel, the local per-(C-S,C-G) traffic counter information on a P-tunnel, the local per-(C-S,C-G) traffic counter information
for traffic received on this P-tunnel can be used to determine the for traffic received on this P-tunnel can be used to determine the
status of the P-tunnel. status of the P-tunnel.
When such a procedure is used, in context where fast restoration When such a procedure is used, in the context where fast restoration
mechanisms are used for the P-tunnels, downstream PEs should be mechanisms are used for the P-tunnels, downstream PEs should be
configured to wait before updating the UMH, to let the P-tunnel configured to wait before updating the UMH, to let the P-tunnel
restoration mechanism happen. A configurable timer MUST be provided restoration mechanism happen. A configurable timer MUST be provided
for this purpose, and it is recommended to provide a reasonable for this purpose, and it is recommended to provide a reasonable
default value for this timer. default value for this timer.
This method can be applicable for instance when a (S,G) flow is This method can be applicable, for instance, when a ((S, G)) flow is
mapped on an S-PMSI. mapped on an S-PMSI.
In cases where this mechanism is used in conjunction with In cases where this mechanism is used in conjunction with
Hot leaf standby, then no prior knowledge of the rate of the Hot leaf standby, then no prior knowledge of the rate of the
multicast streams is required ; downstream PEs can compare reception multicast streams is required; downstream PEs can compare reception
on the two P-tunnels to determine when one of them is down. on the two P-tunnels to determine when one of them is down.
3.1.6. BFD Discriminator 3.1.6. BFD Discriminator
P-tunnel status can be derived from the status of a multipoint BFD P-tunnel status can be derived from the status of a multipoint BFD
session [I-D.ietf-bfd-multipoint] whose discriminator is advertized session [I-D.ietf-bfd-multipoint] whose discriminator is advertised
along with an x-PMSI A-D route. along with an x-PMSI A-D route.
This document defines the format and ways of usingr a new BGP
attribute called the "BGP- BFD attribute". This is an optional
transitive BGP attribute. The format of this attribute is defined as
follows:
+-------------------------------+
| Flags (1 octet) |
+-------------------------------+
| BFD Discriminator (4 octets) |
+-------------------------------+
The Flags field has the following format:
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
| reserved |
+-+-+-+-+-+-+-+-+
3.1.6.1. Upstream PE Procedures 3.1.6.1. Upstream PE Procedures
When it is desired to track the P-Tunnel status using BFD, the When it is desired to track the P-tunnel status using p2mp BFD
Upstream PE MUST include the BGP-BFD Attribute in the x-PMSI A-D session, the Upstream PE:
Route.
If a P-Tunnel is already signaled, and then it is desired to track o MUST initiate BFD session and set bfd.SessionType = MultipointHead
the P-Tunnel status using BFD, x-PMSI A-D Route must be re-sent with as described in [I-D.ietf-bfd-multipoint];
the same attributes as before, but the BGP-BFD Attribute MUST be
included.
If P-Tunnel is already signaled, and P-Tunnel status tracked using o MUST use [Ed.note] address as destination IP address when
BFD and it is desired to stop tracking P-Tunnel status using BFD, transmitting BFD control packets;
then x-PMSI A-D Route MUST be re-sent with the same attributes as
before, but the BGP-BFD Attribute MUST be excluded. o MUST use the IP address of the Upstream PE as source IP address
when transmitting BFD control packets;
o MUST include the BGP-BFD Attribute in the x-PMSI A-D Route with
BFD Discriminator value set to My Discriminator value.
If tracking of the P-tunnel by using a p2mp BFD session is to be
enabled after the P-tunnel has been already signaled, the the
procedure described above MUST be followed. Note that x-PMSI A-D
Route MUST be re-sent with exactly the same attributes as before and
the BGP-BFD Attribute included.
If P-tunnel is already signaled, and P-tunnel status tracked using
the p2mp BFD session and it is desired to stop tracking P-tunnel
status using BFD, then:
o x-PMSI A-D Route MUST be re-sent with exactly the same attributes
as before, but the BGP-BFD Attribute MUST be excluded;
o the p2mp BFD session SHOULD be deleted.
3.1.6.2. Downstream PE Procedures 3.1.6.2. Downstream PE Procedures
On receiving the BFD attribute in the x-PMSI A-D Route, the On receiving the BGP-BFD Attribute in the x-PMSI A-D Route, the
Downstream PE MUST associate the received discriminator with the Downstream PE:
P-Tunnel originating from the Root PE. Once the Downstream PE start
getting the BFD probes from the Upstream PE with the given
discriminator, the BFD session will be declared up and will then be
used to track the health of the P-Tunnel.
If the Downstream PE does not receive BFD probes for a P-Tunnel from o MUST associate the received BFD discriminator value with the
the Upstream PE for Detection Time, the BFD session would be brought P-tunnel originating from the Root PE;
down. And, it would declare the P-tunnel associated with the
discriminator as down.
Downstream PE then can then initiate a switchover of the traffic from o MUST create p2mp BFD session and set bfd.SessionType =
the Primary Tunnel, to the Standby Tunnel. MultipointTail as described in [I-D.ietf-bfd-multipoint];
When Downstream PE's P-Tunnel is already up, it receives new x-PMSI o MUST use the source IP address of a BFD control packet, the value
A-D Route with BGP-BFD attribute, it must accept the x-PMSI A-D Route of BFD Discriminator from the BGP-BFD Attribute to properly
and associate the discriminator with the P-tunnel. When the BFD demultiplex BFD sessions;
probes are received with the given discriminator, the BFD session is
declared up.
When Downstream PE's P-Tunnel is already up, and is tracked with BFD, After the state of the p2mp BFD session is up, i.e. bfd.SessionState
and it receives new x-PMSI A-D Route without BGP-BFD attribute, it = Up, the session state will then be used to track the health of the
must accept the x-PMSI A-D Route the BFD session should be declared P-tunnel.
admin down. Receiver node SHOULD not switch the traffic to the
Standby P-tunnel.
When such a procedure is used, in context where fast restoration According to [I-D.ietf-bfd-multipoint], if the Downstream PE receives
mechanisms are used for the P-tunnels, leaf PEs should be configured Down or AdminDown in the State field of the BFD control packet or
to wait before updating the UMH, to let the P-tunnel restoration associated with the BFD session Detection Timer expires, the BFD
mechanism happen. A configurable timer MUST be provided for this session state is down, i.e. bfd.SessionState = Down. When the BFD
purpose, and it is recommended to provide a reasonable default value session state is Down, then the P-tunnel associated with the BFD
for this timer. session as down MUST be declared down. Then The Downstream PE MAY
initiate a switchover of the traffic from the Primary Upstream PE to
the Standby Upstream PE.
3.1.6.3. BGP-BFD Attribute If the Downstream PE's P-tunnel is already up when the Downstream PE
receives the new x-PMSI A-D Route with BGP-BFD Attribute, the
Downstream PE MUST accept the x-PMSI A-D Route and associate the
value of BFD Discriminator field with the P-tunnel. The Upstream PE
MUST follow procedures listed above in this section to bring the p2mp
BFD session up and use it to monitor the state of the associated
P-tunnel.
This document defines and uses a new BGP attribute called the "BGP- If the Downstream PE's P-tunnel is already up, its state being
BFD attribute". This is an optional transitive BGP attribute. The monitored by the p2mp BFD session, and the Downstream PE receives the
format of this attribute is defined as follows: new x-PMSI A-D Route without the BGP-BFD Attribute, the Downstream
PE:
+-------------------------------+ o MUST accept the x-PMSI A-D Route;
| Flags (1 octet) |
+-------------------------------+
| BFD Discriminator (4 octets) |
+-------------------------------+
The Flags field has the following format: o MUST stop receiving BFD control packets for this p2mp BFD session;
0 1 2 3 4 5 6 7 o SHOULD delete the p2mp BFD session associated with the P-tunnel;
+-+-+-+-+-+-+-+-+
| reserved | o SHOULD NOT switch the traffic to the Standby Upstream PE.
+-+-+-+-+-+-+-+-+
When such a procedure is used, in the context where fast restoration
mechanisms are used for the P-tunnels, leaf PEs should be configured
to wait before updating the UMH, to let the P-tunnel restoration
mechanism happen. A configurable timer MUST be provided for this
purpose, and it is recommended to provide a reasonable default value
for this timer.
3.1.7. Per PE-CE link BFD Discriminator 3.1.7. Per PE-CE link BFD Discriminator
The following approach is proposed for fast failover on PE-CE link The following approach is defined for the fast failover in response
failures, in which UMH selection for a given C-multicast route takes to the detection of PE-CE link failures, in which UMH selection for a
into account the state of a BFD session dedicated to the state of the given C-multicast route takes into account the state of the BFD
upstream PE-CE link. session associated with the state of the upstream PE-CE link.
3.1.7.1. Upstream PE Procedures 3.1.7.1. Upstream PE Procedures
For each protected PE-CE link, the upstream PE initiates a multipoint For each protected PE-CE link, the upstream PE initiates a multipoint
BFD session [I-D.ietf-bfd-multipoint] toward downstream PEs, with a BFD session [I-D.ietf-bfd-multipoint] as MultipointHead toward
trigger causing such a session to be torn down if the associated PE- downstream PEs. A downstream PE monitors the state of the p2mp
CE link is detected as down. session as MultipointTail and MAY interpret transition of the BFD
session into Down state as the indication of the associated PE-CE
link being down.
For SSM groups, the upstream PE advertises a (S,G) S-PMSI A-D route For SSM groups, the upstream PE advertises an ((S, G)) S-PMSI A-D
or wildcard (S,*) S-PMSI A-D route for each received SSM (S,G) route or wildcard (S,*) S-PMSI A-D route for each received SSM ((S,
C-multicast route for which protection is desired. For each ASM G)) C-multicast route for which protection is desired. For each ASM
(S,G) C-multicast route for which protection is desired, the upstream ((S, G)) C-multicast route for which protection is desired, the
PE advertises a (S,G) S-PMSI A-D route. For each ASM (*,G) upstream PE advertises a ((S, G)) S-PMSI A-D route. For each ASM
C-Multicast route for which protection is desired, the upstream PE (*,G) C-Multicast route for which protection is desired, the upstream
advertises a wildcard (*,G) S-PMSI A-D route. Note that all S-PMSI PE advertises a wildcard (*,G) S-PMSI A-D route. Note that all
A-D routes can signal the same P-Tunnel, so there is no need for a S-PMSI A-D routes can signal the same P-tunnel, so there is no need
new P-Tunnel for each S-PMSI A-D route. Multicast flows for which for a new P-tunnel for each S-PMSI A-D route. Multicast flows for
protection is desired is controlled by configuration/policy on the which protection is desired is controlled by configuration/policy on
upstream PE. The protected link is the RPF PE-CE interface towards the upstream PE. The protected link is the RPF PE-CE interface
the src/RP. The upstream PE advertises the BFD discriminator of the towards the src/RP. The upstream PE advertises the BFD discriminator
protected link in the S-PMSI A-D route. If the route to the src/RP of the protected link in the S-PMSI A-D route. If the route to the
changes such that the RPF interface is changed to be a new PE-CE src/RP changes such that the RPF interface is changed to be a new PE-
interface, then the upstream PE will update the S-PMSI A-D route with CE interface, then the upstream PE will update the S-PMSI A-D route
the BFD discriminator associated with the new RPF link. with included BGP-BFD Attribute so that value of the BFD
Discriminator is associated with the new RPF link.
3.1.7.2. Downstream PE Procedures 3.1.7.2. Downstream PE Procedures
If an S-PMSI A-D route bound to a given C-multicast is signaled with If an S-PMSI A-D route bound to a given C-multicast is signaled with
a multipoint BFD session, then the upstream PE is considered during a multipoint BFD session, then the upstream PE is considered during
UMH selection for the C-multicast if and only if the corresponding UMH selection for the C-multicast if and only if the corresponding
BFD session is not known to be down. Whenever the BFD session goes BFD session is not in state Down, i.e bfd.SessionState != Down.
down the Provider Tunnel will be considered down, and the downstream Whenever the state of the BFD session changes to Down the Provider
PE will switch to the backup Provider Tunnel. Note that the Provider Tunnel will be considered down, and the downstream PE will switch to
Tunnel is considered down only for the C-multicast states that match the backup Provider Tunnel. Note that the Provider Tunnel is
to an S-PMSI A-D route which signaled the BFD discriminator of a BFD considered down only for the C-multicast states that match to an
session which is down. S-PMSI A-D route which included BGP-BFD Attribute with the BFD
Discriminator of the p2mp BFD session which is down.
4. Standby C-multicast route 4. Standby C-multicast route
The procedures described below are limited to the case where the site The procedures described below are limited to the case where the site
that contains C-S is connected to exactly two PEs. The procedures that contains C-S is connected to exactly two PEs. The procedures
require all the PEs of that MVPN to follow the single forwarder PE require all the PEs of that MVPN to follow the single forwarder PE
selection, as specified in [RFC6513]. The procedures assume that if selection, as specified in [RFC6513]. The procedures assume that if
a site of a given MVPN that contains C-S is dual-homed to two PEs, a site of a given MVPN that contains C-S is dual-homed to two PEs,
then all the other sites of that MVPN would have two unicast VPN then all the other sites of that MVPN would have two unicast VPN
routes (VPN-IPv4 or VPN-IPv6) routes to C-S, each with its own RD. routes (VPN-IPv4 or VPN-IPv6) routes to C-S, each with its own RD.
As long as C-S is reachable via both PEs, a given downstream PE will As long as C-S is reachable via both PEs, a given downstream PE will
select one of the PEs connected to C-S as its Upstream PE with select one of the PEs connected to C-S as its Upstream PE with
respect to C-S. We will refer to the other PE connected to C-S as respect to C-S. We will refer to the other PE connected to C-S as
the "Standby Upstream PE". Note that if the connectivity to C-S the "Standby Upstream PE". Note that if the connectivity to C-S
through the Primary Upstream PE becomes unavailable, then the PE will through the Primary Upstream PE becomes unavailable, then the PE will
select the Standby Upstream PE as its Upstream PE with respect to select the Standby Upstream PE as its Upstream PE with respect to
C-S. When the Primary PE later becomes available, then the PE will C-S. When the Primary PE later becomes available, then the PE will
select the Primary Upstream PE again as its Upstream PE. This is select the Primary Upstream PE again as its Upstream PE. This is
referred to as "revertive" behavior, and MUST be supported. Non- referred to as "revertive" behavior and MUST be supported. Non-
revertive behavior would refer to the behavior of continuing to revertive behavior would refer to the behavior of continuing to
select the backup PE as the UMH even after the Primary has come up. select the backup PE as the UMH even after the Primary has come up.
This non-revertive behavior can also be optionally supported by an This non-revertive behavior can also be optionally supported by an
implementation and would be enabled through some configuration. implementation and would be enabled through some configuration.
For readability, in the following sub-sections, the procedures are For readability, in the following sub-sections, the procedures are
described for BGP C-multicast Source Tree Join routes, but they apply described for BGP C-multicast Source Tree Join routes, but they apply
equally to BGP C-multicast Shared Tree Join routes failover for the equally to BGP C-multicast Shared Tree Join routes failover for the
case where the customer RP is dual-homed (substitute "C-RP" to case where the customer RP is dual-homed (substitute "C-RP" to
"C-S"). "C-S").
skipping to change at page 10, line 22 skipping to change at page 11, line 20
[RFC6514] the PE sends the C-multicast route with RT that identifies [RFC6514] the PE sends the C-multicast route with RT that identifies
the Upstream PE selected by the PE originating the route. As long as the Upstream PE selected by the PE originating the route. As long as
C-S is reachable via the Primary Upstream PE, the Upstream PE is the C-S is reachable via the Primary Upstream PE, the Upstream PE is the
Primary Upstream PE. If C-S is reachable only via the Standby Primary Upstream PE. If C-S is reachable only via the Standby
Upstream PE, then the Upstream PE is the Standby Upstream PE. Upstream PE, then the Upstream PE is the Standby Upstream PE.
If C-S is reachable via both the Primary and the Standby Upstream PE, If C-S is reachable via both the Primary and the Standby Upstream PE,
then in addition to sending the C-multicast route with an RT that then in addition to sending the C-multicast route with an RT that
identifies the Primary Upstream PE, the PE also originates and sends identifies the Primary Upstream PE, the PE also originates and sends
a C-multicast route with an RT that identifies the Standby Upstream a C-multicast route with an RT that identifies the Standby Upstream
PE. This route, that has the semantic of being a 'standby' PE. This route, that has the semantics of being a 'standby'
C-multicast route, is further called a "Standby BGP C-multicast C-multicast route, is further called a "Standby BGP C-multicast
route", and is constructed as follows: route", and is constructed as follows:
o the NLRI is constructed as the original C-multicast route, except o the NLRI is constructed as the original C-multicast route, except
that the RD is the same as if the C-multicast route was built that the RD is the same as if the C-multicast route was built
using the standby PE as the UMH (it will carry the RD associated using the standby PE as the UMH (it will carry the RD associated
to the unicast VPN route advertized by the standby PE for S) to the unicast VPN route advertised by the standby PE for S)
o SHOULD carry the "Standby PE" BGP Community (this is a new BGP o SHOULD carry the "Standby PE" BGP Community (this is a new BGP
Community, see Section 7) Community, see Section 7)
The normal and the standby C-multicast routes must have their Local The normal and the standby C-multicast routes must have their Local
Preference attribute adjusted so that, if two C-multicast routes with Preference attribute adjusted so that, if two C-multicast routes with
same NLRI are received by a BGP peer, one carrying the "Standby PE" same NLRI are received by a BGP peer, one carrying the "Standby PE"
attribute and the other one *not* carrying the "Standby PE" attribute and the other one *not* carrying the "Standby PE"
community, then preference is given to the one *not* carrying the community, then preference is given to the one *not* carrying the
"Standby PE" attribute. Such a situation can happen when, for "Standby PE" attribute. Such a situation can happen when, for
instance due to transient unicast routing inconsistencies, two instance, due to transient unicast routing inconsistencies, two
different downstream PEs consider different upstream PEs to be the different downstream PEs consider different upstream PEs to be the
primary one ; in that case, without any precaution taken, both primary one; in that case, without any precaution taken, both
upstream PEs would process a standby C-multicast route and possibly upstream PEs would process a standby C-multicast route and possibly
stop forwarding at the same time. For this purpose, routes that stop forwarding at the same time. For this purpose, routes that
carry the "Standby PE" BGP Community MUST have the LOCAL_PREF carry the "Standby PE" BGP Community MUST have the LOCAL_PREF
attribute set to zero. attribute set to zero.
Note that, when a PE advertizes such a Standby C-multicast join for Note that, when a PE advertises such a Standby C-multicast join for
an (S,G) it must join the corresponding P-tunnel. an ((S, G)) it must join the corresponding P-tunnel.
If at some later point the local PE determines that C-S is no longer If at some later point the local PE determines that C-S is no longer
reachable through the Primary Upstream PE, the Standby Upstream PE reachable through the Primary Upstream PE, the Standby Upstream PE
becomes the Upstream PE, and the local PE re-sends the C-multicast becomes the Upstream PE, and the local PE re-sends the C-multicast
route with RT that identifies the Standby Upstream PE, except that route with RT that identifies the Standby Upstream PE, except that
now the route does not carry the Standby PE BGP Community (which now the route does not carry the Standby PE BGP Community (which
results in replacing the old route with a new route, with the only results in replacing the old route with a new route, with the only
difference between these routes being the presence/absence of the difference between these routes being the presence/absence of the
Standby PE BGP Community). Standby PE BGP Community).
skipping to change at page 11, line 43 skipping to change at page 12, line 38
C-multicast route, the PE MAY install VRF PIM state corresponding C-multicast route, the PE MAY install VRF PIM state corresponding
to this BGP Source Tree Join route (the result will be that Join to this BGP Source Tree Join route (the result will be that Join
messages will be sent to the CE toward C-S, and that the PE will messages will be sent to the CE toward C-S, and that the PE will
receive (C-S,C-G) traffic) receive (C-S,C-G) traffic)
b) based on local policy, as soon as the PE receives this Standby BGP b) based on local policy, as soon as the PE receives this Standby BGP
C-multicast route, the PE MAY forward (C-S, C-G) traffic to other C-multicast route, the PE MAY forward (C-S, C-G) traffic to other
PEs through a P-tunnel independently of the reachability of C-S PEs through a P-tunnel independently of the reachability of C-S
through some other PE. [note that this implies also doing (a)] through some other PE. [note that this implies also doing (a)]
Doing neither (a), nor (b) for a given (C-S,C-G) is called "cold root Doing neither (a) or (b) for a given (C-S,C-G) is called "cold root
standby". standby".
Doing (a) but not (b) for a given (C-S,C-G) is called "warm root Doing (a) but not (b) for a given (C-S,C-G) is called "warm root
standby". standby".
Doing (b) (which implies also doing (a)) for a given (C-S,C-G) is Doing (b) (which implies also doing (a)) for a given (C-S,C-G) is
called "hot root standby". called "hot root standby".
Note that, if an upstream PE uses an S-PMSI only policy, it shall Note that, if an upstream PE uses an S-PMSI only policy, it shall
advertise an S-PMSI for an (S,G) as soon as it receives a C-multicast advertise an S-PMSI for an ((S, G)) as soon as it receives a
route for (S,G), normal or Standby ; i.e. it shall not wait for C-multicast route for ((S, G)), normal or Standby; i.e. it shall not
receiving a non-Standby C-multicast route before advertising the wait for receiving a non-Standby C-multicast route before advertising
corresponding S-PMSI. the corresponding S-PMSI.
Section 9.3.2 of [RFC6514], describes the procedures of sending a Section 9.3.2 of [RFC6514], describes the procedures of sending a
Source-Active A-D result as a result of receiving the C-multicast Source-Active A-D result as a result of receiving the C-multicast
route. These procedures should be followed for both the normal and route. These procedures should be followed for both the normal and
Standby C-multicast routes. Standby C-multicast routes.
4.3. Reachability determination 4.3. Reachability determination
The standby PE can use the following information to determine that The standby PE can use the following information to determine that
C-S can or cannot be reached through the primary PE: C-S can or cannot be reached through the primary PE:
skipping to change at page 12, line 37 skipping to change at page 13, line 31
Section 3.1 (without using the UMH selection procedures of Section 3.1 (without using the UMH selection procedures of
Section 3) Section 3)
o other mechanisms MAY be used o other mechanisms MAY be used
4.4. Inter-AS 4.4. Inter-AS
If the non-segmented inter-AS approach is used, the procedures in If the non-segmented inter-AS approach is used, the procedures in
section 4 can be applied. section 4 can be applied.
When multicast VPNs are used in a inter-AS context with the segmented When multicast VPNs are used in an inter-AS context with the
inter-AS approach described in section 8.2 of [RFC6514], the segmented inter-AS approach described in section 8.2 of [RFC6514],
procedures in this section can be applied. the procedures in this section can be applied.
A pre-requisite for the procedures described below to be applied for A pre-requisite for the procedures described below to be applied for
a source of a given MVPN is: a source of a given MVPN is:
o that any PE of this MVPN receives two Inter-AS I-PMSI auto- o that any PE of this MVPN receives two Inter-AS I-PMSI auto-
discovery routes advertized by the AS of the source (or more) discovery routes advertised by the AS of the source (or more)
o that these Inter-AS I-PMSI autodiscovery routes have distinct o that these Inter-AS I-PMSI auto-discovery routes have distinct
Route Distinguishers (as described in item "(2)" of section 9.2 of Route Distinguishers (as described in item "(2)" of section 9.2 of
[RFC6514]). [RFC6514]).
As an example, these conditions will be satisfied when the source is As an example, these conditions will be satisfied when the source is
dual homed to an AS that connects to the receiver AS through two ASBR dual-homed to an AS that connects to the receiver AS through two ASBR
using auto-configured RDs. using auto-configured RDs.
4.4.1. Inter-AS procedures for downstream PEs, ASBR fast failover 4.4.1. Inter-AS procedures for downstream PEs, ASBR fast failover
The following procedure is applied by downstream PEs of an AS, for a The following procedure is applied by downstream PEs of an AS, for a
source S in a remote AS. source S in a remote AS.
Additionally to choosing an Inter-AS I-PMSI autodiscovery route Additionally, to choosing an Inter-AS I-PMSI auto-discovery route
advertized from the AS of the source to construct a C-multicast advertised from the AS of the source to construct a C-multicast
route, as described in section 11.1.3 [RFC6514] a downstream PE will route, as described in section 11.1.3 [RFC6514] a downstream PE will
choose a second Inter-AS I-PMSI autodiscovery route advertized from choose a second Inter-AS I-PMSI auto-discovery route advertised from
the AS of the source and use this route to construct and advertise a the AS of the source and use this route to construct and advertise a
Standby C-multicast route (C-multicast route carrying the Standby Standby C-multicast route (C-multicast route carrying the Standby
extended community) as described in Section 4.1. extended community) as described in Section 4.1.
4.4.2. Inter-AS procedures for ASBRs 4.4.2. Inter-AS procedures for ASBRs
When an upstream ASBR receives a C-multicast route, and at least one When an upstream ASBR receives a C-multicast route, and at least one
of the RTs of the route matches one of the ASBR Import RT, the ASBR of the RTs of the route matches one of the ASBR Import RT, the ASBR
locates an Inter-AS I-PMSI A-D route whose RD and Source AS matches locates an Inter-AS I-PMSI A-D route whose RD and Source AS matches
the RD and Source AS carried in the C-multicast route. If the match the RD and Source AS carried in the C-multicast route. If the match
is found, and C-multicast route carries the Standby PE BGP Community, is found, and C-multicast route carries the Standby PE BGP Community,
then the ASBR performs as follows: then the ASBR performs as follows:
o if the route was received over iBGP ; the route is expected to o if the route was received over iBGP; the route is expected to have
have a LOCAL_PREF attribute set to zero and it should be re- a LOCAL_PREF attribute set to zero and it should be re-advertised
advertized in eBGP with a MED attribute (MULTI_EXIT_DISC) set to in eBGP with a MED attribute (MULTI_EXIT_DISC) set to the highest
the highest possible value (0xffff) possible value (0xffff)
o if the route was received over eBGP ; the route is expected to o if the route was received over eBGP; the route is expected to have
have a MED attribute set of 0xffff and should be re-advertized in a MED attribute set of 0xffff and should be re-advertised in iBGP
iBGP with a LOCAL_PREF attribute set to zero with a LOCAL_PREF attribute set to zero
Other ASBR procedures are applied without modification. Other ASBR procedures are applied without modification.
5. Hot leaf standby 5. Hot leaf standby
The mechanisms defined in sections Section 4 and Section 3 can be The mechanisms defined in sections Section 4 and Section 3 can be
used together as follows. used together as follows.
The principle is that, for a given VRF (or possibly only for a given The principle is that, for a given VRF (or possibly only for a given
C-S,C-G): C-S,C-G):
skipping to change at page 14, line 17 skipping to change at page 15, line 12
whether a (primary) BGP C-multicast route or a Standby BGP whether a (primary) BGP C-multicast route or a Standby BGP
C-multicast route for that state (or both) C-multicast route for that state (or both)
o downstream PEs accept traffic from the primary or standby tunnel, o downstream PEs accept traffic from the primary or standby tunnel,
based on the status of the tunnel (based on Section 3) based on the status of the tunnel (based on Section 3)
Other combinations of the mechanisms proposed in Section 4) and Other combinations of the mechanisms proposed in Section 4) and
Section 3 are for further study. Section 3 are for further study.
Note that the same level of protection would be achievable with a Note that the same level of protection would be achievable with a
simple C-multicast Source Tree Join route advertized to both the simple C-multicast Source Tree Join route advertised to both the
primary and secondary upstream PEs (carrying as Route Target extended primary and secondary upstream PEs (carrying as Route Target extended
communities, the values of the VRF Route Import attribute of each VPN communities, the values of the VRF Route Import attribute of each VPN
route from each upstream PEs). The advantage of using the Standby route from each upstream PEs). The advantage of using the Standby
semantic for is that, supposing that downstream PEs always advertise semantic for is that, supposing that downstream PEs always advertise
a Standby C-multicast route to the secondary upstream PE, it allows a Standby C-multicast route to the secondary upstream PE, it allows
to choose the protection level through a change of configuration on to choose the protection level through a change of configuration on
the secondary upstream PE, without requiring any reconfiguration of the secondary upstream PE, without requiring any reconfiguration of
all the downstream PEs. all the downstream PEs.
6. Duplicate packets 6. Duplicate packets
Multicast VPN specifications [RFC6513] impose that a PE only forwards Multicast VPN specifications [RFC6513] impose that a PE only forwards
to CEs the packets coming from the expected usptream PE to CEs the packets coming from the expected upstream PE
(Section 9.1). (Section 9.1).
We highlight the reader's attention to the fact that the respect of We highlight the reader's attention to the fact that the respect of
this part of multicast VPN specifications is especially important this part of multicast VPN specifications is especially important
when two distinct upstream PEs are susceptible to forward the same when two distinct upstream PEs are susceptible to forward the same
traffic on P-tunnels at the same time in steady state. This will be traffic on P-tunnels at the same time in the steady state. This will
the case when "hot root standby" mode is used (Section 4), and which be the case when "hot root standby" mode is used (Section 4), and
can also be the case if procedures of Section 3 are used and (a) the which can also be the case if procedures of Section 3 are used and
rules determining the status of a tree are not the same on two (a) the rules determining the status of a tree are not the same on
distinct downstream PEs or (b) the rule determining the status of a two distinct downstream PEs or (b) the rule determining the status of
tree depend on conditions local to a PE (e.g. the PE-P upstream link a tree depend on conditions local to a PE (e.g. the PE-P upstream
being up). link being up).
7. IANA Considerations 7. IANA Considerations
Allocation is expected from IANA for the BGP "Standby PE" community. Allocation is expected from IANA for the BGP "Standby PE" community.
(TBC) (TBC)
[Note to RFC Editor: this section may be removed on publication as an [Note to RFC Editor: this section may be removed on publication as an
RFC.] RFC.]
8. Security Considerations 8. Security Considerations
9. Acknowledgments
9. Acknowledgements
The authors want to thank Greg Reaume, Eric Rosen, and Jeffrey Zhang The authors want to thank Greg Reaume, Eric Rosen, and Jeffrey Zhang
for their review and useful feedback. for their review and useful feedback.
10. Contributor Addresses 10. Contributor Addresses
Below is a list of other contributing authors in alphabetical order: Below is a list of other contributing authors in alphabetical order:
Rahul Aggarwal Rahul Aggarwal
Arktan Arktan
skipping to change at page 17, line 17 skipping to change at page 18, line 16
Mountain View, CA 94043 Mountain View, CA 94043
USA USA
Email: kanwar.singh@alcatel-lucent.com Email: kanwar.singh@alcatel-lucent.com
11. References 11. References
11.1. Normative References 11.1. Normative References
[I-D.ietf-bfd-multipoint] [I-D.ietf-bfd-multipoint]
Katz, D., Ward, D., and S. Pallagatti, "BFD for Multipoint Katz, D., Ward, D., Networks, J., and G. Mirsky, "BFD for
Networks", draft-ietf-bfd-multipoint-09 (work in Multipoint Networks", draft-ietf-bfd-multipoint-16 (work
progress), April 2017. in progress), April 2018.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC4875] Aggarwal, R., Papadimitriou, D., and S. Yasukawa, [RFC4875] Aggarwal, R., Ed., Papadimitriou, D., Ed., and S.
"Extensions to Resource Reservation Protocol - Traffic Yasukawa, Ed., "Extensions to Resource Reservation
Engineering (RSVP-TE) for Point-to-Multipoint TE Label Protocol - Traffic Engineering (RSVP-TE) for Point-to-
Switched Paths (LSPs)", RFC 4875, May 2007. Multipoint TE Label Switched Paths (LSPs)", RFC 4875,
DOI 10.17487/RFC4875, May 2007,
<https://www.rfc-editor.org/info/rfc4875>.
[RFC6513] Aggarwal, R., Bandi, S., Cai, Y., Morin, T., Rekhter, Y., [RFC6513] Rosen, E., Ed. and R. Aggarwal, Ed., "Multicast in MPLS/
Rosen, E., Wijnands, I., and S. Yasukawa, "Multicast in BGP IP VPNs", RFC 6513, DOI 10.17487/RFC6513, February
MPLS/BGP IP VPNs", RFC 6513, February 2012. 2012, <https://www.rfc-editor.org/info/rfc6513>.
[RFC6514] Aggarwal, R., Rosen, E., Morin, T., and Y. Rekhter, "BGP [RFC6514] Aggarwal, R., Rosen, E., Morin, T., and Y. Rekhter, "BGP
Encodings and Procedures for Multicast in MPLS/BGP IP Encodings and Procedures for Multicast in MPLS/BGP IP
VPNs", RFC 6514, February 2012. VPNs", RFC 6514, DOI 10.17487/RFC6514, February 2012,
<https://www.rfc-editor.org/info/rfc6514>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
11.2. Informative References 11.2. Informative References
[RFC4090] Pan, P., Swallow, G., and A. Atlas, "Fast Reroute [RFC4090] Pan, P., Ed., Swallow, G., Ed., and A. Atlas, Ed., "Fast
Extensions to RSVP-TE for LSP Tunnels", RFC 4090, May Reroute Extensions to RSVP-TE for LSP Tunnels", RFC 4090,
2005. DOI 10.17487/RFC4090, May 2005,
<https://www.rfc-editor.org/info/rfc4090>.
[RFC7431] Karan, A., Filsfils, C., Wijnands, IJ., and B. Decraene, [RFC7431] Karan, A., Filsfils, C., Wijnands, IJ., Ed., and B.
"Multicast-only Fast Re-Route", RFC 7431, August 2015. Decraene, "Multicast-Only Fast Reroute", RFC 7431,
DOI 10.17487/RFC7431, August 2015,
<https://www.rfc-editor.org/info/rfc7431>.
Authors' Addresses Authors' Addresses
Thomas Morin (editor) Thomas Morin (editor)
Orange Orange
2, avenue Pierre Marzin 2, avenue Pierre Marzin
Lannion 22307 Lannion 22307
France France
Email: thomas.morin@orange-ftgroup.com Email: thomas.morin@orange-ftgroup.com
Robert Kebler (editor) Robert Kebler (editor)
Juniper Networks Juniper Networks
1194 North Mathilda Ave. 1194 North Mathilda Ave.
Sunnyvale, CA 94089 Sunnyvale, CA 94089
U.S.A. U.S.A.
Email: rkebler@juniper.net Email: rkebler@juniper.net
Greg Mirsky (editor)
ZTE Corp.
Email: gregimirsky@gmail.com
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