Internet DRAFT - draft-morin-bess-mvpn-fast-failover
draft-morin-bess-mvpn-fast-failover
Network Working Group T. Morin, Ed.
Internet-Draft Orange
Intended status: Standards Track R. Kebler, Ed.
Expires: January 3, 2016 Juniper Networks
July 6, 2015
Multicast VPN fast upstream failover
draft-morin-bess-mvpn-fast-failover-02
Abstract
This document defines multicast VPN extensions and procedures that
allow fast failover for upstream failures, by allowing downstream PEs
to take into account the status of Provider-Tunnels (P-tunnels) when
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
standby upstream PE.
Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
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This Internet-Draft will expire on January 3, 2016.
Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Provisions Relating to IETF Documents
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. UMH Selection based on tunnel status . . . . . . . . . . . . 3
3.1. Determining the status of a tunnel . . . . . . . . . . . 4
3.1.1. mVPN tunnel root tracking . . . . . . . . . . . . . . 5
3.1.2. PE-P Upstream link status . . . . . . . . . . . . . . 5
3.1.3. P2MP RSVP-TE tunnels . . . . . . . . . . . . . . . . 5
3.1.4. Leaf-initiated P-tunnels . . . . . . . . . . . . . . 6
3.1.5. (S,G) counter information . . . . . . . . . . . . . . 6
3.1.6. BFD Discriminator . . . . . . . . . . . . . . . . . . 6
3.1.7. Per PE-CE link BFD Discriminator . . . . . . . . . . 8
4. Standby C-multicast route . . . . . . . . . . . . . . . . . . 9
4.1. Downstream PE behavior . . . . . . . . . . . . . . . . . 9
4.2. Upstream PE behavior . . . . . . . . . . . . . . . . . . 10
4.3. Reachability determination . . . . . . . . . . . . . . . 11
4.4. Inter-AS . . . . . . . . . . . . . . . . . . . . . . . . 12
4.4.1. Inter-AS procedures for downstream PEs, ASBR fast
failover . . . . . . . . . . . . . . . . . . . . . . 12
4.4.2. Inter-AS procedures for ASBRs . . . . . . . . . . . . 12
5. Hot leaf standby . . . . . . . . . . . . . . . . . . . . . . 13
6. Duplicate packets . . . . . . . . . . . . . . . . . . . . . . 14
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
8. Security Considerations . . . . . . . . . . . . . . . . . . . 14
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
10. Contributor Addresses . . . . . . . . . . . . . . . . . . . . 14
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
11.1. Normative References . . . . . . . . . . . . . . . . . . 16
11.2. Informative References . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
In the context of multicast in BGP/MPLS VPNs, it is desirable to
provide mechanisms allowing fast recovery of connectivity on
different types of failures. This document addresses failures of
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elements in the provider network that are upstream of PEs connected
to VPN sites with receivers.
The sections 3 and 4 describe two independent mechanisms, allowing
different levels of resiliency, and providing different failure
coverage:
o Section 3 describes local procedures allowing an egress PE (a PE
connected to a receiver site) to take into account the status of
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 when used alone, but can be used with the following
sections for a "fast failover" solution.
o Section 4 describes protocol extensions that can speed up failover
by not requiring any multicast VPN routing message exchange at
recovery time.
Moreover, section 5 describes a "hot leaf standby" mechanism, that
uses a combination of these two mechanisms. This approach has
similarities with the solution described in [I-D.mofrr] to improve
failover times when PIM routing is used in a network given some
topology and metric constraints.
2. Terminology
The terminology used in this document is the terminology defined in
[RFC6513] and [RFC6514].
3. UMH Selection based on tunnel status
Current multicast VPN specifications [RFC6513], section 5.1, describe
the procedures used by a multicast VPN downstream PE to determine
what the upstream multicast hop (UMH) is for a said (C-S,C-G).
The procedure described here is an OPTIONAL procedure that consists
of having a downstream PE take into account the status of P-tunnels
rooted at each possible upstream PEs, for including or not including
each said PE in the list of candidate UMHs for a said (C-S,C-G)
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
considered for UMH selection, which will result in the downstream PE
to failover to the upstream PE which is next in the list of
candidates.
A downstream PE monitors the status of the tunnels of UMHs that are
ahead of the current one. Whenever the downstream PE determines that
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one of these tunnels is no longer "known to down", the PE selects the
UMH corresponding to that as the new UMH.
More precisely, UMH determination for a said (C-S,C-G) will consider
the UMH candidates in the following order:
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
(b) do not advertise any I- or S- PMSI applicable to the said
(C-S,C-G) but have associated a VRF Route Import BGP attribute to
the unicast VPN route for S (this is necessary to avoid
considering some invalid UMH PEs that use a policy where no I-PMSI
is advertized for a said VRF and where only S-PMSI are used, the
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
carried over the advertized S-PMSI)
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
ensure a graceful fallback to the basic MVPN UMH selection
procedures in the hypothetical case where a false negative would
occur when determining the status of all tunnels
For a said downstream PE and a said VRF, the P-tunnel corresponding
to a said upstream PE for a said (C-S,C-G) state is the S-PMSI tunnel
advertized 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
advertized by that PE and imported into that VRF.
Note that this documents 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
that MVPN would have two unicast VPN routes (VPN-IPv4 or VPN-IPv6)
routes to C-S, each with its own RD.
3.1. Determining the status of a tunnel
Different factors can be considered to determine the "status" of a
P-tunnel and are described in the following sub-sections. The
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
(please see Section 6), and some of them will produce a result that
may be different for different downstream PEs. Thus what is called
the "status" of a P-tunnel in this section, is not a characteristic
of the tunnel in itself, but is the status of the tunnel, *as seen
from a particular downstream PE*. Additionally, some of the
following methods determine the ability of downstream PE to receive
traffic on the P-tunnel and not specifically on the status of the
P-tunnel itself. This could be referred to as "P-tunnel reception
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status", but for simplicity, we will use the terminology of P-tunnel
"status" for all of these methods.
Depending on the criteria used to determine the status of a P-tunnel,
there may be an interaction with another resiliency mechanism used
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
separate sub-section below.
3.1.1. mVPN tunnel root tracking
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,
is reachable through unicast routing tables. In this case the
downstream PE can immediately update its UMH when the reachability
condition changes.
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
address in the PMSI tunnel attribute.
If BGP next-hop tracking is done for VPN routes, and the root address
of a said tunnel happens to be the same as the next-hop address in
the BGP autodiscovery route advertising the tunnel, then this
mechanisms may be omitted for this tunnel, as it will not bring any
specific benefit.
3.1.2. PE-P Upstream link status
A condition to consider a tunnel status as up can be that the last-
hop link of the P-tunnel is up.
This method should not be used when there is a fast restoration
mechanism (such as MPLS FRR [RFC4090]) in place for the link.
3.1.3. P2MP RSVP-TE tunnels
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
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
state for the LSP and is based on procedures in [RFC4875]. In this
case the downstream PE can immediately update its UMH when the
reachability condition changes.
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
LSP changes state from up to down as determined by procedures in
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[RFC4875], the status of the corresponding P-Tunnel SHOULD be re-
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
considered a valid UMH.
3.1.4. Leaf-initiated P-tunnels
A PE can be removed from the UMH candidate list for a said (S,G) if
the P-tunnel for this S,G (I or S , depending) is leaf triggered
(PIM, mLDP), but for some reason internal to the protocol the
upstream one-hop branch of the tunnel from P to PE cannot be built.
In this case the downstream PE can immediately update its UMH when
the reachability condition changes.
3.1.5. (S,G) counter information
In cases, where the downstream node can be configured so that the
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
for traffic received on this P-tunnel can be used to determine the
status of the P-tunnel.
When such a procedure is used, in context where fast restoration
mechanisms are used for the P-tunnels, downstream 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.
This method can be applicable for instance when a (S,G) flow is
mapped on an S-PMSI.
In cases where this mechanism is used in conjunction with
Hot leaf standby, then no prior knowledge of the rate of the
multicast streams is required ; downstream PEs can compare reception
on the two P-tunnels to determine when one of them is down.
3.1.6. BFD Discriminator
P-tunnel status can be derived from the status of a BFD session whose
discriminator is advertized along with an x-PMSI A-D route.
3.1.6.1. Root PE Procedures
When it is desired to track the P-Tunnel status using BFD, the Root
PE MUST include the BGP-BFD Attribute in the x-PMSI A-D Route.
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If a P-Tunnel is already signaled, and then it is desired to track
the P-Tunnel status using BFD, x-PMSI A-D Route must be re-sent with
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
BFD and it is desired to stop tracking P-Tunnel status using BFD,
then x-PMSI A-D Route MUST be re-sent with the same attributes as
before, but the BGP-BFD Attribute MUST be excluded.
3.1.6.2. Leaf PE Procedures
On receiving the BFD attribute in the x-PMSI A-D Route, the Leaf PE
MUST associate the received discriminator with the P-Tunnel
originating from the Root PE. Once the Leaf PE start getting the BFD
probes from the Root PE with the said discriminator, the BFD session
will be declared up and will then be used to track the health of the
P-Tunnel.
If the Leaf PE does not receive BFD probes for a P-Tunnel from the
Root PE for Detection Time, the BFD session would be brought down.
And, it would declare the P-tunnel associated with the discriminator
as down.
Leaf PE then can then initiate a switchover of the traffic from the
Primary Tunnel, to the Standby Tunnel.
When Leaf PE's P-Tunnel is already up, it receives new x-PMSI A-D
Route with BGP-BFD attribute, it must accept the x-PMSI A-D Route and
associate the discriminator with the P-tunnel. When the BFD probes
are received with the said discriminator, the BFD session is declared
up.
When Leaf PE's P-Tunnel is already up, and is tracked with BFD, and
it receives new x-PMSI A-D Route without BGP-BFD attribute, it must
accept the x-PMSI A-D Route the BFD session should be declared 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
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.
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3.1.6.3. BGP-BFD Attribute
This document defines and uses 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 |
+-+-+-+-+-+-+-+-+
3.1.7. Per PE-CE link BFD Discriminator
The following approach is proposed for fast failover on PE-CE link
failures, in which UMH selection for a said (S,G) takes into account
the state of a BFD session dedicated to the state of the upstream PE-
CE link.
If this approach is enabled:
o each upstream PE: for each PE-CE link for which this protection is
wanted, initiates a multipoint BFD session toward downstream PEs,
with a trigger causing such a session to be torn down if the
associated PE-CE link is detected as down.
o each upstream PE: for each prefix of a PE-CE link for which
protection is wanted, advertizes a wildcard S-PMSI covering the
sources inside this prefix, and signals along with this S-PMSI the
multipoint BFD session discriminator associated with the PE-CE
link. (note that all these S-PMSIs can perfectly use the same
P-tunnel)
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o each downstream PE: if an S-PMSI bound to a said (S,G) is signaled
with a multipoint BFD session, then the upstream PE is considered
during UMH selection for (S,G) if and only if the corresponding
BFD session is up. Whenever the BFD session goes down the S-PMSI
P-tunnel will be considered down and the downstream PE will switch
to the backup P-tunnel. Note that the P-tunnel is considered down
only for the (S,G) states that match to an S-PMSI signaling the
BFD discriminator of a BFD session which is down
4. Standby C-multicast route
The procedures described below are limited to the case where the site
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
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,
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.
As long as C-S is reachable via both PEs, a said downstream PE will
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
the "Standby Upstream PE". Note that if the connectivity to C-S
through the Primary Upstream PE becomes unavailable, then the PE will
select the Standby Upstream PE as its Upstream PE with respect to
C-S.
For readability, in the following sub-sections, the procedures are
described for BGP C-multicast Source Tree Join routes, but they apply
equally to BGP C-multicast Shared Tree Join routes failover for the
case where the customer RP is dual-homed (substitute "C-RP" to
"C-S").
4.1. Downstream PE behavior
When a (downstream) PE connected to some site of an MVPN needs to
send a C-multicast route (C-S, C-G), then following the procedures
specified in Section "Originating C-multicast routes by a PE" of
[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
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
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,
then in addition to sending the C-multicast route with an RT that
identifies the Primary Upstream PE, the PE also originates and sends
a C-multicast route with an RT that identifies the Standby Upstream
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PE. This route, that has the semantic of being a 'standby'
C-multicast route, is further called a "Standby BGP C-multicast
route", and is constructed as follows:
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
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)
o SHOULD carry the "Standby PE" BGP Community (this is a new BGP
Community, see Section 7)
The normal and the standby C-multicast routes must have their Local
Preference attribute adjusted so that, if two C-multicast routes with
same NLRI are received by a BGP peer, one 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
"Standby PE" attribute. Such a situation can happen when, for
instance due to transient unicast routing inconsistencies, two
different downstream PEs consider different upstream PEs to be the
primary one ; in that case, without any precaution taken, both
upstream PEs would process a standby C-multicast route and possibly
stop forwarding at the same time. For this purpose a Standby BGP
C-multicast route MUST have the LOCAL_PREF attribute set to zero.
Note that, when a PE advertizes such a Standby C-multicast join for
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
reachable through the Primary Upstream PE, the Standby Upstream PE
becomes the Upstream PE, and the local PE re-sends the C-multicast
route with RT that identifies the Standby Upstream PE, except that
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
difference between these routes being the presence/absence of the
Standby PE BGP Community).
4.2. Upstream PE behavior
When a PE receives a C-multicast route for a particular (C-S, C-G),
and the RT carried in the route results in importing the route into a
particular VRF on the PE, if the route carries the Standby PE BGP
Community, then the PE performs as follows:
when the PE determines that C-S is not reachable through some
other PE, the PE SHOULD install VRF PIM state corresponding to
this Standby BGP C-multicast route (the result will be that a PIM
Join message will be sent to the CE towards C-S, and that the PE
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will receive (C-S,C-G) traffic), and the PE SHOULD forward (C-S,
C-G) traffic received by the PE to other PEs through a P-tunnel
rooted at the PE.
Furthermore, irrespective of whether C-S carried in that route is
reachable through some other PE:
a) based on local policy, as soon as the PE receives this Standby BGP
C-multicast route, the PE MAY install VRF PIM state corresponding
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
receive (C-S,C-G) traffic)
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
PEs through a P-tunnel independently of the reachability of C-S
through some other PE. [note that this implies also doing (a)]
Doing neither (a), nor (b) for a said (C-S,C-G) is called "cold root
standby".
Doing (a) but not (b) for a said (C-S,C-G) is called "warm root
standby".
Doing (b) (which implies also doing (a)) for a said (C-S,C-G) is
called "hot root standby".
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
route for (S,G), normal or Standby ; i.e. it shall not wait for
receiving a non-Standby C-multicast route before advertising the
corresponding S-PMSI.
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
route. These procedures should be followed for both the normal and
Standby C-multicast routes.
4.3. Reachability determination
The standby PE can use the following information to determine that
C-S can or cannot be reached through the primary PE:
o presence/absence of a unicast VPN route toward C-S
o supposing that the standby PE is an egress of the tunnel rooted at
the Primary PE, the standby PE can determine the reachability of
C-S through the Primary PE based on the status of this tunnel,
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determined thanks to the same criteria as the ones described in
Section 3.1 (without using the UMH selection procedures of
Section 3)
o other mechanisms MAY be used
4.4. Inter-AS
If the non-segmented inter-AS approach is used, the procedures in
section 4 can be applied.
When multicast VPNs are used in a inter-AS context with the segmented
inter-AS approach described in section 8.2 of [RFC6514], the
procedures in this section can be applied.
A pre-requisite for the procedures described below to be applied for
a source of a said MVPN is:
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)
o that these Inter-AS I-PMSI autodiscovery routes have distinct
Route Distinguishers (as described in item "(2)" of section 9.2 of
[RFC6514]).
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
using auto-configured RDs.
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
source S in a remote AS.
Additionally to choosing an Inter-AS I-PMSI autodiscovery route
advertized from the AS of the source to construct a C-multicast
route, as described in section 11.1.3 [RFC6514] a downstream PE will
choose a second Inter-AS I-PMSI autodiscovery route advertized from
the AS of the source and use this route to construct and advertise a
Standby C-multicast route (C-multicast route carrying the Standby
extended community) as described in Section 4.1.
4.4.2. Inter-AS procedures for ASBRs
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
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
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is found, and C-multicast route carries the Standby PE BGP Community,
then the ASBR performs as follows:
o if the route was received over iBGP ; the route is expected to
have a LOCAL_PREF attribute set to zero and it should be re-
advertized in eBGP with a MED attribute (MULTI_EXIT_DISC) set to
the highest possible value (0xffff)
o if the route was received over eBGP ; the route is expected to
have a MED attribute set of 0xffff and should be re-advertized in
iBGP with a LOCAL_PREF attribute set to zero
Other ASBR procedures are applied without modification.
5. Hot leaf standby
The mechanisms defined in sections Section 4 and Section 3 can be
used together as follows.
The principle is that, for a said VRF (or possibly only for a said
C-S,C-G):
o downstream PEs advertise a Standby BGP C-multicast route (based on
Section 4)
o upstream PEs use the "hot standby" optional behavior and thus will
forward traffic for a said multicast state as soon as they have
whether a (primary) BGP C-multicast route or a Standby BGP
C-multicast route for that state (or both)
o downstream PEs accept traffic from the primary or standby tunnel,
based on the status of the tunnel (based on Section 3)
Other combinations of the mechanisms proposed in Section 4) and
Section 3 are for further study.
Note that the same level of protection would be achievable with a
simple C-multicast Source Tree Join route advertized to both the
primary and secondary upstream PEs (carrying as Route Target extended
communities, the values of the VRF Route Import attribute of each VPN
route from each upstream PEs). The advantage of using the Standby
semantic for is that, supposing that downstream PEs always advertise
a Standby C-multicast route to the secondary upstream PE, it allows
to choose the protection level through a change of configuration on
the secondary upstream PE, without requiring any reconfiguration of
all the downstream PEs.
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6. Duplicate packets
Multicast VPN specifications [RFC6513] impose that a PE only forwards
to CEs the packets coming from the expected usptream PE
(Section 9.1).
We highlight the reader's attention to the fact that the respect of
this part of multicast VPN specifications is especially important
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
the case when "hot root standby" mode is used (Section 4), and which
can also be the case if procedures of Section 3 are used and (a) the
rules determining the status of a tree are not the same on two
distinct downstream PEs or (b) the rule determining the status of a
tree depend on conditions local to a PE (e.g. the PE-P upstream link
being up).
7. IANA Considerations
Allocation is expected from IANA for the BGP "Standby PE" community.
(TBC)
[Note to RFC Editor: this section may be removed on publication as an
RFC.]
8. Security Considerations
9. Acknowledgements
The authors want to thank Greg Reaume and Eric Rosen for their review
and useful feedback.
10. Contributor Addresses
Below is a list of other contributing authors in alphabetical order:
Rahul Aggarwal
Arktan
Email: raggarwa_1@yahoo.com
Nehal Bhau
Alcatel-Lucent, Inc.
701 E Middlefield Rd
Mountain View, CA 94043
USA
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Email: Nehal.Bhau@alcatel-lucent.com
Clayton Hassen
Bell Canada
2955 Virtual Way
Vancouver
CANADA
Email: Clayton.Hassen@bell.ca
Wim Henderickx
Alcatel-Lucent
Copernicuslaan 50
Antwerp 2018
Belgium
Email: wim.henderickx@alcatel-lucent.com
Pradeep Jain
Alcatel-Lucent, Inc.
701 E Middlefield Rd
Mountain View, CA 94043
USA
Email: pradeep.jain@alcatel-lucent.com
Jayant Kotalwar
Alcatel-Lucent, Inc.
701 E Middlefield Rd
Mountain View, CA 94043
USA
Email: Jayant.Kotalwar@alcatel-lucent.com
Praveen Muley
Alcatel-Lucent
701 East Middlefield Rd
Mountain View, CA 94043
U.S.A.
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Email: praveen.muley@alcatel-lucent.com
Ray (Lei) Qiu
Juniper Networks
1194 North Mathilda Ave.
Sunnyvale, CA 94089
U.S.A.
Email: rqiu@juniper.net
Yakov Rekhter
Juniper Networks
1194 North Mathilda Ave.
Sunnyvale, CA 94089
U.S.A.
Email: yakov@juniper.net
Kanwar Singh
Alcatel-Lucent, Inc.
701 E Middlefield Rd
Mountain View, CA 94043
USA
Email: kanwar.singh@alcatel-lucent.com
11. References
11.1. Normative References
[I-D.ietf-bfd-multipoint]
Katz, D., Ward, D., and S. Pallagatti, "BFD for Multipoint
Networks", draft-ietf-bfd-multipoint-06 (work in
progress), January 2015.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
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[RFC4875] Aggarwal, R., Papadimitriou, D., and S. Yasukawa,
"Extensions to Resource Reservation Protocol - Traffic
Engineering (RSVP-TE) for Point-to-Multipoint TE Label
Switched Paths (LSPs)", RFC 4875, May 2007.
[RFC6513] Aggarwal, R., Bandi, S., Cai, Y., Morin, T., Rekhter, Y.,
Rosen, E., Wijnands, I., and S. Yasukawa, "Multicast in
MPLS/BGP IP VPNs", RFC 6513, February 2012.
[RFC6514] Aggarwal, R., Rosen, E., Morin, T., and Y. Rekhter, "BGP
Encodings and Procedures for Multicast in MPLS/BGP IP
VPNs", RFC 6514, February 2012.
11.2. Informative References
[I-D.mofrr]
Karan, A., Filsfils, C., Farinacci, D., Decraene, B.,
Leymann, N., and T. Telkamp, "Multicast only Fast Re-
Route", draft-ietf-rtgwg-mofrr-08 (work in progress),
February 2015.
[RFC4090] Pan, P., Swallow, G., and A. Atlas, "Fast Reroute
Extensions to RSVP-TE for LSP Tunnels", RFC 4090, May
2005.
Authors' Addresses
Thomas Morin (editor)
Orange
2, avenue Pierre Marzin
Lannion 22307
France
Email: thomas.morin@orange-ftgroup.com
Robert Kebler (editor)
Juniper Networks
1194 North Mathilda Ave.
Sunnyvale, CA 94089
U.S.A.
Email: rkebler@juniper.net
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