< draft-ietf-lsr-isis-flood-reflection-03.txt   draft-ietf-lsr-isis-flood-reflection-04.txt >
Network Working Group A. Przygienda Network Working Group A. Przygienda
Internet-Draft C. Bowers Internet-Draft C. Bowers
Intended status: Standards Track Juniper Intended status: Standards Track Juniper
Expires: January 12, 2022 Y. Lee Expires: 24 April 2022 Y. Lee
A. Sharma A. Sharma
Comcast Comcast
R. White R. White
Juniper Juniper
July 11, 2021 21 October 2021
IS-IS Flood Reflection IS-IS Flood Reflection
draft-ietf-lsr-isis-flood-reflection-03 draft-ietf-lsr-isis-flood-reflection-04
Abstract Abstract
This document describes an optional ISIS extension that allows the This document describes a backwards compatible, optional ISIS
creation of IS-IS flood reflection topologies. Flood reflection extension that allows the creation of IS-IS flood reflection
allows the creation of topologies where L1 areas provide transit topologies. Flood reflection allows topologies in which L1 areas
forwarding for L2 destinations within an L2 topology. It provide transit forwarding for L2 using all available L1 nodes
accomplishes this by creating L2 flood reflection adjacencies within internally. It accomplishes this by creating L2 flood reflection
each L1 area. The L2 flood reflection adjacencies are used to flood adjacencies within each L1 area. Those adjacencies are used to flood
L2 LSPDUs, and they are used in the L2 SPF computation. However, L2 LSPDUs, and they are used in the L2 SPF computation. However,
they are not used for forwarding. This arrangement gives the L2 they are not used for forwarding within the flood reflection cluster.
topology better scaling properties. In addition, only those routers This arrangement gives the L2 topology significantly better scaling
directly participating in flood reflection have to support the properties. As additional benefit, only those routers directly
feature. This allows for the incremental deployment of scalable L1 participating in flood reflection have to support the feature. This
transit areas in an existing network, without the necessity of allows for the incremental deployment of scalable L1 transit areas in
upgrading other routers in the network. an existing network, without the necessity of upgrading other routers
in the network.
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", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119]. document are to be interpreted as described in RFC 2119 [RFC2119].
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
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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-
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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 January 12, 2022. This Internet-Draft will expire on 24 April 2022.
Copyright Notice Copyright Notice
Copyright (c) 2021 IETF Trust and the persons identified as the Copyright (c) 2021 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.
Table of Contents Table of Contents
1. Description . . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Further Details . . . . . . . . . . . . . . . . . . . . . . . 8 2. Description . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Flood Reflection TLV . . . . . . . . . . . . . . . . . . . . 9 3. Further Details . . . . . . . . . . . . . . . . . . . . . . . 8
4. Flood Reflection Discovery Sub-TLV . . . . . . . . . . . . . 10 4. Flood Reflection TLV . . . . . . . . . . . . . . . . . . . . 9
5. Flood Reflection Adjacency Sub-TLV . . . . . . . . . . . . . 11 5. Flood Reflection Discovery Sub-TLV . . . . . . . . . . . . . 10
6. Flood Reflection Discovery . . . . . . . . . . . . . . . . . 11 6. Flood Reflection Discovery Tunnel Type Sub-Sub-TLV . . . . . 11
7. Flood Reflection Adjacency Formation . . . . . . . . . . . . 12 7. Flood Reflection Adjacency Sub-TLV . . . . . . . . . . . . . 12
8. Redistribution of Prefixes . . . . . . . . . . . . . . . . . 13 8. Flood Reflection Discovery . . . . . . . . . . . . . . . . . 13
9. Route Computation . . . . . . . . . . . . . . . . . . . . . . 13 9. Flood Reflection Adjacency Formation . . . . . . . . . . . . 14
10. Special Considerations . . . . . . . . . . . . . . . . . . . 14 10. Route Computation . . . . . . . . . . . . . . . . . . . . . . 14
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14 10.1. Tunnel Based Deployment . . . . . . . . . . . . . . . . 15
11.1. New IS-IS TLV Codepoint . . . . . . . . . . . . . . . . 14 10.2. No Tunnel Deployment . . . . . . . . . . . . . . . . . . 15
11.2. Sub TLVs for TLV 242 . . . . . . . . . . . . . . . . . . 15 11. Redistribution of Prefixes . . . . . . . . . . . . . . . . . 15
11.3. Sub TLVs for TLV 22, 23, 25, 141, 222, and 223 . . . . . 15 12. Special Considerations . . . . . . . . . . . . . . . . . . . 16
12. Security Considerations . . . . . . . . . . . . . . . . . . . 15 13. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16
13. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 15 13.1. New IS-IS TLV Codepoint . . . . . . . . . . . . . . . . 16
14. References . . . . . . . . . . . . . . . . . . . . . . . . . 15 13.2. Sub TLVs for TLV 242 . . . . . . . . . . . . . . . . . . 17
14.1. Informative References . . . . . . . . . . . . . . . . . 15 13.3. Sub-sub TLVs for Flood Reflection Discovery sub-TLV . . 17
14.2. Normative References . . . . . . . . . . . . . . . . . . 16 13.4. Sub TLVs for TLV 22, 23, 25, 141, 222, and 223 . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16 14. Security Considerations . . . . . . . . . . . . . . . . . . . 17
15. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 18
16. References . . . . . . . . . . . . . . . . . . . . . . . . . 18
16.1. Informative References . . . . . . . . . . . . . . . . . 18
16.2. Normative References . . . . . . . . . . . . . . . . . . 18
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 19
1. Description 1. Glossary
This section is introduced first with the intention of allowing quick
reference later in the document to terms introduced
Flood Reflector:
Node configured to connect L2 only to flood reflector clients and
reflect (reflood) ISIS L2 LSPs amongst them.
Flood Reflector Client:
Node configured to build flood reflector adjacencies and normal L2
nodes.
Flood Reflector Adjacency:
ISIS L2 adjacency limited by one end being client and the other
reflector and agreeing on the same Flood Reflector Cluster ID.
Flood Reflector Cluster:
Collection of clients and flood reflectors configured with the
same cluster identifier.
Tunnel Deployment:
Deployment where flood reflector clients build a full mesh of
tunnels in L1 to "shortcut" forwarding of L2 traffic through the
cluster.
No Tunnel Deployment:
Deployment where flood reflector clients redistribute L2
reachability into L1 to allow forwarding through the cluster
without underlying tunnels.
2. Description
Due to the inherent properties of link-state protocols the number of Due to the inherent properties of link-state protocols the number of
IS-IS routers within a flooding domain is limited by processing and IS-IS routers within a flooding domain is limited by processing and
flooding overhead on each node. While that number can be maximized flooding overhead on each node. While that number can be maximized
by well written implementations and techniques such as exponential by well written implementations and techniques such as exponential
back-offs, IS-IS will still reach a saturation point where no further back-offs, IS-IS will still reach a saturation point where no further
routers can be added to a single flooding domain. In some L2 routers can be added to a single flooding domain. In some L2
backbone deployment scenarios, this limit presents a significant backbone deployment scenarios, this limit presents a significant
challenge. challenge.
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| | | | | | | | | | | | | | | |
| | | | +----------+ | | | | | +----------+ |
| | | | | | | | | | | | | | | |
| | | | +-----+ | | | | | | +-----+ | |
| | | | | | | | | | | | | | | |
+----+ ++----+-+-+ | +-+-+--+-++ +----+ +----+ ++----+-+-+ | +-+-+--+-++ +----+
| R3 | | R12 | | L2 adjacency | R32 | | R6 | | R3 | | R12 | | L2 adjacency | R32 | | R6 |
| L2 +--+ L1/L2 +------------------------------------+ L1/L2 +--+ L2 | | L2 +--+ L1/L2 +------------------------------------+ L1/L2 +--+ L2 |
| | | | | | | | | | | | | | | | | |
+----+ +-------+----+ +-------+ +----+ +----+ +-------+----+ +-------+ +----+
Figure 2: Example topology represented in L2 with a full mesh of
Figure 2: Example topology represented in L2 with a full mesh of L2 L2 adjacencies between L1/L2 nodes
adjacencies between L1/L2 nodes
BGP, as specified in [RFC4271], faced a similar scaling problem, BGP, as specified in [RFC4271], faced a similar scaling problem,
which has been solved in many networks by deploying BGP route which has been solved in many networks by deploying BGP route
reflectors [RFC4456]. We note that BGP route reflectors do not reflectors [RFC4456]. We note that BGP route reflectors do not
necessarily have to be in the forwarding path of the traffic. This necessarily have to be in the forwarding path of the traffic. This
incongruity of forwarding and control path for BGP route reflectors incongruity of forwarding and control path for BGP route reflectors
allows the control plane to scale independently of the forwarding allows the control plane to scale independently of the forwarding
plane. plane.
We propose here a similar solution for IS-IS. A simple example of We propose here a similar solution for IS-IS. A simple example of
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| L2 +--+ L1/L2 +-----------+ L1/L2 +--------------+ L1/L2 +--+ L2 | | L2 +--+ L1/L2 +-----------+ L1/L2 +--------------+ L1/L2 +--+ L2 |
| | | | L2 adj | flood | L2 adj | | | | | | | | L2 adj | flood | L2 adj | | | |
+----+ +-------+ over |reflector| over +-------+ +----+ +----+ +-------+ over |reflector| over +-------+ +----+
tunnel +--+---+--+ tunnel tunnel +--+---+--+ tunnel
+----+ +-------+ | | +-------+ +----+ +----+ +-------+ | | +-------+ +----+
| R3 | | R12 +--------------+ +-----------------+ R32 | | R6 | | R3 | | R12 +--------------+ +-----------------+ R32 | | R6 |
| L2 +--+ L1/L2 | L2 adj L2 adj | L1/L2 +--+ L2 | | L2 +--+ L1/L2 | L2 adj L2 adj | L1/L2 +--+ L2 |
| | | | over over | | | | | | | | over over | | | |
+----+ +-------+ tunnel tunnel +-------+ +----+ +----+ +-------+ tunnel tunnel +-------+ +----+
Figure 3: Example topology represented in L2 with L2 adjacencies from Figure 3: Example topology represented in L2 with L2 adjacencies
each L1/L2 node to a single flood reflector from each L1/ L2 node to a single flood reflector
As illustrated in Figure 3, when R21 plays the role of flood As illustrated in Figure 3, when R21 plays the role of flood
reflector, it provides L2 connectivity among all of the previously reflector, it provides L2 connectivity among all of the previously
disconnected L2 islands by reflooding all L2 LSPDUs. At the same disconnected L2 islands by reflooding all L2 LSPDUs. At the same
time, R20 and R22 remain L1-only routers. L1-only routers and time, R20 and R22 remain L1-only routers. L1-only routers and
L1-only links are not visible in L2. In this manner, the flood L1-only links are not visible in L2. In this manner, the flood
reflector allows us provide L2 control plane connectivity in a reflector allows us provide L2 control plane connectivity in a
scalable manner. scalable manner.
As described so far, the solution illustrated in Figure 3 relies only As described so far, the solution illustrated in Figure 3 relies only
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the L2 adjacency to R21 over L1 links instead. This would allow the the L2 adjacency to R21 over L1 links instead. This would allow the
forwarding within the L1 area to use the L1-only nodes and links forwarding within the L1 area to use the L1-only nodes and links
shown in Figure 1 as well. It allows networks to be built that use shown in Figure 1 as well. It allows networks to be built that use
the entire forwarding capacity of the L1 areas, while at the same the entire forwarding capacity of the L1 areas, while at the same
time introducing control plane scaling benefits provided by L2 flood time introducing control plane scaling benefits provided by L2 flood
reflectors. reflectors.
This document defines all extensions necessary to support flood This document defines all extensions necessary to support flood
reflector deployment: reflector deployment:
o A 'flood reflector adjacency' for all the adjacencies built for * A 'flood reflector adjacency' for all the adjacencies built for
the purpose of reflecting flooding information. This allows these the purpose of reflecting flooding information. This allows these
'flood reflectors' to participate in the IS-IS control plane 'flood reflectors' to participate in the IS-IS control plane
without being used in the forwarding plane. This is a purely without being used in the forwarding plane. This is a purely
local operation on the L1/L2 ingress; it does not require local operation on the L1/L2 ingress; it does not require
replacing or modifying any routers not involved in the reflection replacing or modifying any routers not involved in the reflection
process. Deployment-wise, it is far less tricky to just upgrade process. Deployment-wise, it is far less tricky to just upgrade
the routers involved in flood reflection rather than have a flag the routers involved in flood reflection rather than have a flag
day on the whole ISIS domain. day on the whole ISIS domain.
o A full mesh of L1 tunnels between the L1/L2 routers, ideally load- * An (optional) full mesh of tunnels between the L1/L2 routers,
balancing across all available L1 links. This harnesses all ideally load-balancing across all available L1 links. This
forwarding paths between the L1/L2 edge nodes without injecting harnesses all forwarding paths between the L1/L2 edge nodes
unneeded state into the L2 flooding domain or creating 'choke without injecting unneeded state into the L2 flooding domain or
points' at the 'flood reflectors' themselves. A solution without creating 'choke points' at the 'flood reflectors' themselves. The
tunnels is also possible by judicious scoping of reachability draft is agnostic as to the tunneling technology used but provides
information between the levels. enough information for automatic establishment of such tunnels.
The discussion of ISIS adjacency formation and/or liveness
discovery on such tunnels is outside the scope of this draft and
is largely choice of the underlying implementation. A solution
without tunnels is also possible by applying judicious scoping of
reachability information between the levels as described in more
details later.
o Some way to support reflector redundancy, and potentially some way * Some way to support reflector redundancy, and potentially some way
to auto-discover and advertise such adjacencies as flood reflector to auto-discover and advertise such adjacencies as flood reflector
adjacencies. Such advertisements may allow L2 nodes outside the adjacencies. Such advertisements may allow L2 nodes outside the
L1 to perform optimizations in the future based on this L1 to perform optimizations in the future based on this
information. information.
2. Further Details 3. Further Details
Several considerations should be noted in relation to such a flood Several considerations should be noted in relation to such a flood
reflection mechanism. reflection mechanism.
First, this allows multi-area IS-IS deployments to scale without any First, this allows multi-area IS-IS deployments to scale without any
major modifications in the IS-IS implementation on most of the nodes major modifications in the IS-IS implementation on most of the nodes
deployed in the network. Unmodified (traditional) L2 routers will deployed in the network. Unmodified (traditional) L2 routers will
compute reachability across the transit L1 area using the flood compute reachability across the transit L1 area using the flood
reflector adjacencies. reflector adjacencies.
Second, the flood reflectors are not required to participate in Second, the flood reflectors are not required to participate in
forwarding traffic through the L1 transit area. These flood forwarding traffic through the L1 transit area. These flood
reflectors can be hosted on virtual devices outside the forwarding reflectors can be hosted on virtual devices outside the forwarding
topology. topology.
Third, astute readers will realize that flooding reflection may cause Third, astute readers will realize that flooding reflection may cause
the use of suboptimal paths. This is similar to the BGP route the use of suboptimal paths. This is similar to the BGP route
reflection suboptimal routing problem described in reflection suboptimal routing problem described in
[ID.draft-ietf-idr-bgp-optimal-route-reflection-19]. The L2 [ID.draft-ietf-idr-bgp-optimal-route-reflection-28]. The L2
computation determines the egress L1/L2 and with that can create computation determines the egress L1/L2 and with that can create
illusions of ECMP where there is none. And in certain scenarios lead illusions of ECMP where there is none. And in certain scenarios lead
to an L1/L2 egress which is not globally optimal. This represents a to an L1/L2 egress which is not globally optimal. This represents a
straightforward instance of the trade-off between the amount of straightforward instance of the trade-off between the amount of
control plane state and the optimal use of paths through the network control plane state and the optimal use of paths through the network
often encountered when aggregating routing information. often encountered when aggregating routing information.
One possible solution to this problem is to expose additional One possible solution to this problem is to expose additional
topology information into the L2 flooding domains. In the example topology information into the L2 flooding domains. In the example
network given, links from router 01 to router 02 can be exposed into network given, links from router 01 to router 02 can be exposed into
L2 even when 01 and 02 are participating in flood reflection. This L2 even when 01 and 02 are participating in flood reflection. This
information would allow the L2 nodes to build 'shortcuts' when the L2 information would allow the L2 nodes to build 'shortcuts' when the L2
flood reflected part of the topology looks more expensive to cross flood reflected part of the topology looks more expensive to cross
distance wise. distance wise.
Another possible variation is for an implementation to approximate Another possible variation is for an implementation to approximate
with the L1 tunnel cost the cost of the underlying topology. with the tunnel cost the cost of the underlying topology.
Redundancy can be achieved by building multiple flood reflectors in
the L1 area. Multiple flood reflectors do not need any
synchronization mechanisms amongst themselves, except standard ISIS
flooding and database maintenance procedures.
On change in either flood reflection role or cluster ID on IIH the Redundancy can be achieved by building multiple flood reflectors in a
adjacency has to be reset. L1 area. Multiple flood reflectors do not need any synchronization
mechanisms amongst themselves, except standard ISIS flooding and
database maintenance procedures.
3. Flood Reflection TLV 4. Flood Reflection TLV
The Flood Reflection TLV is a new top-level TLV that MAY appear in The Flood Reflection TLV is a new top-level TLV that MAY appear in L2
IIHs. The Flood Reflection TLV indicates the flood reflector cluster IIHs. The Flood Reflection TLV indicates the flood reflector cluster
(based on Flood Reflection Cluster ID) that a given router is (based on Flood Reflection Cluster ID) that a given router is
configured to participate in. It also indicates whether the router configured to participate in. It also indicates whether the router
is configured to play the role of either flood reflector or flood is configured to play the role of either flood reflector or flood
reflector client. The Flood Reflection Cluster ID and flood reflector client. The Flood Reflection Cluster ID and flood
reflector roles advertised in the IIHs are used to ensure that flood reflector roles advertised in the IIHs are used to ensure that flood
reflector adjacencies are only formed between a flood reflector and reflector adjacencies are only formed between a flood reflector and
flood reflector client, and that the Flood Reflection Cluster IDs flood reflector client, and that the Flood Reflection Cluster IDs
match. The Flood Reflection TLV has the following format: match. The Flood Reflection TLV has the following format:
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flood reflector client. When this bit is NOT set, the router acts flood reflector client. When this bit is NOT set, the router acts
as a flood reflector. On a given router, the same value of the as a flood reflector. On a given router, the same value of the
C-bit MUST be advertised across all interfaces advertising the C-bit MUST be advertised across all interfaces advertising the
Flood Reflection TLV in IIHs. Flood Reflection TLV in IIHs.
RESERVED: This field is reserved for future use. It MUST be set to RESERVED: This field is reserved for future use. It MUST be set to
0 when sent and MUST be ignored when received. 0 when sent and MUST be ignored when received.
Flood Reflection Cluster ID: Flood Reflection Cluster Identifier. Flood Reflection Cluster ID: Flood Reflection Cluster Identifier.
These same 32-bit value MUST be assigned to all of the flood These same 32-bit value MUST be assigned to all of the flood
reflectors and flood reflector clients in the L1 area. The value reflectors and flood reflector clients in the same L1 area. The
MUST be unique across different L1 areas within the IGP domain. value MUST be unique across different L1 areas within the IGP
On a given router, the same value of the Flood Reflection Cluster domain. On a given router, the same value of the Flood Reflection
ID MUST be advertised across all interfaces advertising the Flood Cluster ID MUST be advertised across all interfaces advertising
Reflection TLV in IIHs. This implies that a flood reflector can the Flood Reflection TLV in IIHs. This implies that a flood
participate in a single L1 area only. reflector can participate in a single L1 area only.
Sub-TLVs: Optional sub-TLVs. For future extensibility, the format Sub-TLVs: Optional sub-TLVs. For future extensibility, the format
of the Flood Reflection TLV allows for the possibility of of the Flood Reflection TLV allows for the possibility of
including optional sub-TLVs. No sub-TLVs of the Flood Reflection including optional sub-TLVs. No sub-TLVs of the Flood Reflection
TLV are defined in this document. TLV are defined in this document.
The Flood Reflection TLV MUST NOT appear more than once in an IIH. A The Flood Reflection TLV SHOULD NOT appear more than once in an IIH.
router receiving multiple Flood Reflection TLVs in the same IIH A router receiving multiple Flood Reflection TLVs in the same IIH
SHOULD use the values in the first TLV. MUST use the values in the first TLV and it SHOULD adequately log
such violations subject to rate limiting.
4. Flood Reflection Discovery Sub-TLV 5. Flood Reflection Discovery Sub-TLV
Flood Reflection Discovery sub-TLV is advertised as a sub-TLV of the Flood Reflection Discovery sub-TLV is advertised as a sub-TLV of the
IS-IS Router Capability TLV-242, defined in [RFC7981]. The Flood IS-IS Router Capability TLV-242, defined in [RFC7981]. The Flood
Reflection Discovery sub-TLV is advertised in L1 LSPs with area Reflection Discovery sub-TLV is advertised in L1 and L2 LSPs with
flooding scope in order to enable the auto-discovery of flood area flooding scope in order to enable the auto-discovery of flood
reflection capabilities and the automatic creation of L2 tunnels to reflection capabilities. The Flood Reflection Discovery sub-TLV has
be used as flood reflector adjacencies. The Flood Reflection the following format:
Discovery sub-TLV has the following format:
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length |C| Reserved | | Type | Length |C| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Flood Reflection Cluster ID | | Flood Reflection Cluster ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: TBD Type: TBD
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C (Client): This bit is set to indicate that the router acts as a C (Client): This bit is set to indicate that the router acts as a
flood reflector client. When this bit is NOT set, the router acts flood reflector client. When this bit is NOT set, the router acts
as a flood reflector. as a flood reflector.
RESERVED: This field is reserved for future use. It MUST be set to RESERVED: This field is reserved for future use. It MUST be set to
0 when sent and MUST be ignored when received. 0 when sent and MUST be ignored when received.
Flood Reflection Cluster ID: The Flood Reflection Cluster Identifier Flood Reflection Cluster ID: The Flood Reflection Cluster Identifier
is the same as that defined in the Flood Reflection TLV. is the same as that defined in the Flood Reflection TLV.
The Flood Reflection Discovery sub-TLV MUST NOT appear more than once The Flood Reflection Discovery sub-TLV SHOULD NOT appear more than
in TLV 242. A router receiving multiple Flood Reflection Discovery once in TLV 242. A router receiving multiple Flood Reflection
sub-TLVs in TLV 242 SHOULD use the values in the first sub-TLV. Discovery sub-TLVs in TLV 242 MUST use the values in the first sub-
TLV and it SHOULD adequately log such violations subject to rate
limiting.
5. Flood Reflection Adjacency Sub-TLV 6. Flood Reflection Discovery Tunnel Type Sub-Sub-TLV
Flood Reflection Discovery Tunnel Type sub-sub-TLV is advertised
optionally as a sub-sub-TLV of the Flood Reflection Discovery Sub-
TLV, defined in Section 5. It allows the automatic creation of L2
tunnels to be used as flood reflector adjacencies and L1 shortcut
tunnels. The Flood Reflection Tunnel Type sub-sub-TLV has the
following format:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+---------------+
| Type | Length | Reserved |F|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Tunnel Encapsulation Attribute |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Type: TBD
Length: The length, in octets, of zero or more of the following
fields.
Reserved: SHOULD be 0 on transmission and ignored on reception.
F Flag: When set indicates flood reflection tunnel endpoint, when
clear, indicates possible L1 shortcut tunnel endpoint.
Tunnel Encapsulation Attribute: Carries encapsulation type and
further attributes necessary for tunnel establishment as defined
in [RFC9012]. Protocol type sub-TLV as defined in [RFC9012] MAY
be included but MUST when F flag is set include according type
that allows carrying of encapsulated ISIS frames. Such tunnel
type MUST provide according mechanisms to carry up to
`originatingL2LSPBufferSize` sized ISIS frames across.
A flood reflector receiving multiple Flood Reflection Discovery
Tunnel Type sub-sub-TLVs in Flood Reflection Discovery sub-TLV with F
flag set SHOULD use one or more of the specified tunnel endpoints to
automatically establish one or more tunnels that will serve as flood
reflection adjacency(-ies).
A flood reflection client receiving multiple Flood Reflection
Discovery Tunnel Type sub-sub-TLVs in Flood Reflection Discovery sub-
TLV with F flag clear from other leaves MAY use one or more of the
specified tunnel endpoints to automatically establish one or more
tunnels that will serve as L1 tunnel shortcuts.
Optional address validation procedures as defined in [RFC9012] MUST
be disregarded.
7. Flood Reflection Adjacency Sub-TLV
The Flood Reflection Adjacency sub-TLV is advertised as a sub-TLV of The Flood Reflection Adjacency sub-TLV is advertised as a sub-TLV of
TLVs 22, 23, 25, 141, 222, and 223. Its presence indicates that a TLVs 22, 23, 25, 141, 222, and 223. Its presence indicates that a
given adjacency is a flood reflector adjacency. It is included in L2 given adjacency is a flood reflector adjacency. It is included in L2
area scope flooded LSPs. Flood Reflection Adjacency sub-TLV has the area scope flooded LSPs. Flood Reflection Adjacency sub-TLV has the
following format: following format:
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
skipping to change at page 11, line 35 skipping to change at page 12, line 44
C (Client): This bit is set to indicate that the router advertising C (Client): This bit is set to indicate that the router advertising
this adjacency is a flood reflector client. When this bit is NOT this adjacency is a flood reflector client. When this bit is NOT
set, the router advertising this adjacency is a flood reflector. set, the router advertising this adjacency is a flood reflector.
RESERVED: This field is reserved for future use. It MUST be set to RESERVED: This field is reserved for future use. It MUST be set to
0 when sent and MUST be ignored when received. 0 when sent and MUST be ignored when received.
Flood Reflection Cluster ID: The Flood Reflection Cluster Identifier Flood Reflection Cluster ID: The Flood Reflection Cluster Identifier
is the same as that defined in the Flood Reflection TLV. is the same as that defined in the Flood Reflection TLV.
The Flood Reflection Adjacency sub-TLV MUST NOT appear more than once The Flood Reflection Adjacency sub-TLV SHOULD NOT appear more than
in a given TLV. A router receiving multiple Flood Reflection once in a given TLV. A router receiving multiple Flood Reflection
Adjacency sub-TLVs in a TLV SHOULD use the values in the first sub- Adjacency sub-TLVs in a TLV MUST use the values in the first sub-TLV
TLV. and it SHOULD adequately log such violations subject to rate
limiting.
6. Flood Reflection Discovery 8. Flood Reflection Discovery
A router participating in flood reflection MUST be configured as an A router participating in flood reflection MUST be configured as an
L1/L2 router. It originates the Flood Reflection Discovery sub-TLV L1/L2 router. It SHOULD originate the Flood Reflection Discovery
with area flooding scope in L1 only. Normally, all routers on the sub-TLV with area flooding scope in L1 and L2. Normally, all routers
edge of the L1 area (those having traditional L2 adjacencies) will on the edge of the L1 area (those having traditional L2 adjacencies)
advertise themselves as route reflector clients. Therefore, a flood will advertise themselves as route reflector clients. Therefore, a
reflector client will have both traditional L2 adjacencies and flood flood reflector client will have both traditional L2 adjacencies and
reflector L2 adjacencies. flood reflector L2 adjacencies.
A router acting as a flood reflector MUST NOT have any traditional L2 A router acting as a flood reflector MUST NOT have any traditional L2
adjacencies. It will be an L1/L2 router only by virtue of having adjacencies. It will be an L1/L2 router only by virtue of having
flood reflector L2 adjacencies. A router desiring to act as a flood flood reflector L2 adjacencies. A router desiring to act as a flood
reflector will advertise itself as such using the Flood Reflection reflector will advertise itself as such using the Flood Reflection
Discovery sub-TLV in L1. Discovery sub-TLV in L1 and L2.
A given flood reflector or flood reflector client can only A given flood reflector or flood reflector client can only
participate in a single cluster, as determined by the value of its participate in a single cluster, as determined by the value of its
Flood Reflection Cluster ID. Flood Reflection Cluster ID and should disregard other routers' TLVs
for flood reflection purposes if the cluster ID is not matching.
Upon reception of Flood Reflection Discovery sub-TLVs, a router Upon reception of Flood Reflection Discovery sub-TLVs, a router
acting as flood reflector client MUST initiate a tunnel towards each acting as flood reflector client SHOULD initiate a tunnel towards
flood reflector with which it shares an Flood Reflection Cluster ID. each flood reflector with which it shares an Flood Reflection Cluster
The L2 adjacencies formed over such tunnels MUST be marked as flood ID using one or more of the tunnel encapsulations provided with F
reflector adjacencies. If the client has a direct L2 adjacency with flag being set. The L2 adjacencies formed over such tunnels MUST be
the flood reflector it SHOULD use it instead of instantiating a new marked as flood reflector adjacencies. If the client or reflector
tunnel. has a direct L2 adjacency with the according remote side it SHOULD
use it instead of instantiating a new tunnel.
In absence of auto-discovery an implementation MAY use statically
configured tunnels to create flood reflection adjacencies.
The ISIS metrics for all flood reflection adjacencies in a cluster
SHOULD be uniform.
Upon reception of Flood Reflection Discover TLVs, a router acting as Upon reception of Flood Reflection Discover TLVs, a router acting as
a flood reflector client MAY initiate tunnels with L1-only a flood reflector client MAY initiate tunnels with L1-only
adjacencies towards all the other flood reflector clients in its adjacencies towards any of the other flood reflector clients with
cluster. These tunnels MAY be used for forwarding to improve the lower router IDs in its cluster using encapsulations with F flag
load-balancing characteristics of the L1 area. clear. These tunnels MAY be used for forwarding to improve the load-
balancing characteristics of the L1 area. If the clients have a
direct L2 adjacency they SHOULD use it instead of instantiating a new
tunnel.
7. Flood Reflection Adjacency Formation 9. Flood Reflection Adjacency Formation
In order to simplify both implementations and network deployments, we In order to simplify both implementations and network deployments,
do not allow the formation of complex hierarchies of flood reflectors this draft does not allow the formation of complex hierarchies of
and clients. All flood reflectors and flood reflector clients in the flood reflectors and clients or allow multiple clusters in a single
same L1 area MUST share the same Flood Reflector Cluster ID. A flood L1 area. Consequently, all flood reflectors and flood reflector
reflector MUST only form flood reflection adjacencies with flood clients in the same L1 area MUST share the same Flood Reflector
reflector clients. A flood reflector MUST NOT form any traditional Cluster ID.
L2 adjacencies. Flood reflector clients MUST only form flood
reflection adjacencies with flood reflectors. Flood reflector A flood reflector MUST only form flood reflection adjacencies with
clients MAY form traditional L2 adjacencies with flood reflector flood reflector clients with matching Cluster ID. A flood reflector
clients or nodes not participating in flood reflection. MUST NOT form any traditional L2 adjacencies.
Flood reflector clients MUST only form flood reflection adjacencies
with flood reflectors with matching Cluster ID.
Flood reflector clients MAY form traditional L2 adjacencies with
flood reflector clients or nodes not participating in flood
reflection. When two clients form traditional L2 adjacency Cluster
ID is disregarded.
The Flood Reflector Cluster ID and flood reflector roles advertised The Flood Reflector Cluster ID and flood reflector roles advertised
in the Flood Reflection TLVs in IIHs are used to ensure that flood in the Flood Reflection TLVs in IIHs are used to ensure that flood
reflection adjacencies that are established meet the above criteria. reflection adjacencies that are established meet the above criteria.
On change in either flood reflection role or cluster ID on IIH on the
local or remote side the adjacency has to be reset and re-established
if possible.
Once a flood reflection adjacency is established, the flood reflector Once a flood reflection adjacency is established, the flood reflector
and the flood reflector client MUST advertise the adjacency by and the flood reflector client MUST advertise the adjacency by
including the Flood Reflection Adjacency Sub-TLV in the Extended IS including the Flood Reflection Adjacency Sub-TLV in the Extended IS
reachability TLV or MT-ISN TLV. reachability TLV or MT-ISN TLV.
8. Redistribution of Prefixes 10. Route Computation
In some scenarios, L2 prefixes need to be redistributed into L1 by
the route reflector clients. However, if a L1 area edge router
doesn't have any L2 flood reflector adjacencies, then it cannot be
the shortest path egress in the L2 topology. Therefore, flood
reflector client SHOULD only redistribute L2 prefixes into L1 if it
has an L2 flood reflector adjacency. The L2 prefixes advertisements
redistributed into L1 SHOULD be normally limited to L2 intra-area
routes (as defined in [RFC7775]), if the information exists to
distinguish them from other L2 prefix advertisements.
On the other hand, in topologies that make use of flood reflection to
hide the structure of L1 areas while still providing transit
forwarding across them, we generally do not need to redistribute L1
prefixes advertisements into L2.
In deployment scenarios where L1 tunnels are not used, all L1/L2 edge
nodes MUST be flood reflector clients.
9. Route Computation
To ensure loop-free routing, the route reflection client MUST follow To ensure loop-free routing, the route reflection client MUST follow
the normal L2 computation to determine L2 routes. This is because the normal L2 computation to determine L2 routes. This is because
nodes outside the L1 area will generally not be aware that flood nodes outside the L1 area will generally not be aware that flood
reflection is being performed. The flood reflection clients need to reflection is being performed. The flood reflection clients need to
produce the same result for the L2 route computation as a router not produce the same result for the L2 route computation as a router not
participating in flood reflection. However, a flood reflector client participating in flood reflection.
will not necessarily use a given L2 route for forwarding. For an L2
route that uses a flood reflection adjacency as a next-hop, the flood
reflection client may use the next-hop from an L1 route instead.
On the reflection client, after L2 and L1 computation, all flood 10.1. Tunnel Based Deployment
reflector adjacencies used as next-hops for L2 routes MUST be
examined and replaced with the correct L1 tunnel next-hop to the
egress. Alternatively, if the ingress has adequate reachability
information to ensure forwarding towards destination via L1 routes,
L2 routes using flood reflector adjacencies as next-hops can be
omitted entirely. Due to the rules in Section 7 the computation in
the resulting topology is relatively simple, the L2 SPF from a flood
reflector client is guaranteed to reach within a hop the Flood
Reflector and in the following hop the L2 egress to which it has a L1
forwarding tunnel. However, if the topology has L2 paths which are
not route reflected and look "shorter" than the path through the
Flood Reflector then the computation will have to track the egress
out of the L1 domain by a more advanced algorithm.
10. Special Considerations In tunnel based option the reflection client, after L2 and L1
computation, MUST examine all L2 routes and replace all flood
reflector adjacencies with the correct underlying tunnel next-hop to
the egress.
10.2. No Tunnel Deployment
In case of deployment without underlying tunnels, the necessary L2
routes are distributed into the area, normally as L2->L1 routes. Due
to the rules in Section 9 the computation in the resulting topology
is relatively simple, the L2 SPF from a flood reflector client is
guaranteed to reach within a hop the Flood Reflector and in the
following hop the L2 egress to which it has a forwarding tunnel
again. All the flood reflector tunnel nexthops in the according L2
route can hence be removed and if the L2 route has no other ECMP L2
nexthops, the L2 route MUST be suppressed in the RIB by some means to
allow the less preferred L2->L1 route to be used to forward traffic
towards the advertising egress.
In the particular case the client has L2 routes which are not route
reflected, those will be naturally preferred (such routes normally
"hot-potato" route of the L1 area). However in the case the L2 route
through the flood reflector egress is "shorter" than such present non
flood reflected L2 routes, the node SHOULD ensure that such routes
are suppressed so the L2->L1 towards the egress still takes
preference. Observe that operationally this can be resolved in a
relatively simple way by configuring flood reflector adjacencies to
have a high metric, i.e. the flood reflector topology becomes "last
resort" and the leaves will try to "hot-potato" out the area as fast
as possible which is normally the desirable behavior.
In deployment scenarios where tunnels are not used, all L1/L2 edge
nodes MUST be ultimately flood reflector clients except during during
transition phase.
11. Redistribution of Prefixes
When L2 prefixes need to be redistributed into L1 by the route
reflector clients a client that does not have any L2 flood reflector
adjacencies MUST NOT redistribute those routes into the area in case
of application of Section 10.2. The L2 prefixes advertisements
redistributed into L1 with flood reflectors SHOULD be normally
limited to L2 intra-area routes (as defined in [RFC7775]), if the
information exists to distinguish them from other other L2 prefix
advertisements.
On the other hand, in topologies that make use of flood reflection to
hide the structure of L1 areas while still providing transit
forwarding across them using tunnels, we generally do not need to
redistribute L1 prefixes advertisements into L2.
12. Special Considerations
In pathological cases setting the overload bit in L1 (but not in L2) In pathological cases setting the overload bit in L1 (but not in L2)
can partition L1 forwarding, while allowing L2 reachability through can partition L1 forwarding, while allowing L2 reachability through
flood reflector adjacencies to exist. In such a case a node cannot flood reflector adjacencies to exist. In such a case a node cannot
replace a route through a flood reflector adjacency with a L1 replace a route through a flood reflector adjacency with a L1
shortcut and the client can use the L2 tunnel to the flood reflector shortcut and the client can use the L2 tunnel to the flood reflector
for forwarding while it MUST initiate an alarm and declare for forwarding while it MUST initiate an alarm and declare
misconfiguration. misconfiguration.
A flood reflector with directly L2 attached prefixes should advertise A flood reflector with directly L2 attached prefixes should advertise
skipping to change at page 14, line 38 skipping to change at page 16, line 43
the L2 prefixes with a 'third-party' next-hop but that would have the L2 prefixes with a 'third-party' next-hop but that would have
less desirable convergence properties than the solution proposed and less desirable convergence properties than the solution proposed and
force a fork-lift of all L2 routers to make sure they disregard such force a fork-lift of all L2 routers to make sure they disregard such
prefixes unless in the same L1 domain as the Flood Reflector. prefixes unless in the same L1 domain as the Flood Reflector.
Depending on pseudo-node choice in case of a broadcast domain with Depending on pseudo-node choice in case of a broadcast domain with
multiple flood reflectors attached this can lead to a partitioned LAN multiple flood reflectors attached this can lead to a partitioned LAN
and hence a router discovering such a condition MUST initiate an and hence a router discovering such a condition MUST initiate an
alarm and declare misconfiguration. alarm and declare misconfiguration.
11. IANA Considerations 13. IANA Considerations
This document requests allocation for the following IS-IS TLVs and This document requests allocation for the following IS-IS TLVs and
Sub-TLVs. Sub-TLVs.
11.1. New IS-IS TLV Codepoint 13.1. New IS-IS TLV Codepoint
This document requests the following IS-IS TLV: This document requests the following IS-IS TLV:
Value Name IIH LSP SNP Purge Value Name IIH LSP SNP Purge
----- --------------------------------- --- --- --- ----- ----- --------------------------------- --- --- --- -----
TBD1 Flood Reflection y n n n TBD1 Flood Reflection y n n n
Suggested value for TBD1 is 161. Suggested value for TBD1 is 161.
11.2. Sub TLVs for TLV 242 13.2. Sub TLVs for TLV 242
This document request the following registration in the "sub-TLVs for This document request the following registration in the "sub-TLVs for
TLV 242" registry. TLV 242" registry.
Type Description Type Description
---- ----------- ---- -----------
TBD2 Flood Reflection Discovery TBD2 Flood Reflection Discovery
Suggested value for TBD2 is 161. Suggested value for TBD2 is 161.
11.3. Sub TLVs for TLV 22, 23, 25, 141, 222, and 223 13.3. Sub-sub TLVs for Flood Reflection Discovery sub-TLV
This document request the following registration in the "sub-sub-TLVs
for Flood Reflection Discovery sub-TLV" registry.
Type Description
---- -----------
TBD3 Flood Reflection Discovery Tunnel Encapsulation Attribute
Suggested value for TBD3 is 161.
13.4. Sub TLVs for TLV 22, 23, 25, 141, 222, and 223
This document requests the following registration in the "sub-TLVs This document requests the following registration in the "sub-TLVs
for TLV 22, 23, 25, 141, 222, and 223" registry. for TLV 22, 23, 25, 141, 222, and 223" registry.
Type Description 22 23 25 141 222 223 Type Description 22 23 25 141 222 223
---- -------------------------------- --- --- --- --- --- --- ---- -------------------------------- --- --- --- --- --- ---
TBD3 Flood Reflector Adjacency y y n y y y TBD4 Flood Reflector Adjacency y y n y y y
Suggested value for TBD3 is 161. Suggested value for TBD4 is 161.
12. Security Considerations 14. Security Considerations
This document introduces no new security concerns to ISIS or other This document introduces no new security concerns to ISIS or other
specifications referenced in this document. specifications referenced in this document.
13. Acknowledgements 15. Acknowledgements
The authors thank Shraddha Hegde, Peter Psenak, and Les Ginsberg for The authors thank Shraddha Hegde, Peter Psenak, Acee Lindem and Les
their thorough review and detailed discussions. Ginsberg for their thorough review and detailed discussions.
14. References 16. References
14.1. Informative References 16.1. Informative References
[ID.draft-ietf-idr-bgp-optimal-route-reflection-19] [ID.draft-ietf-idr-bgp-optimal-route-reflection-28]
Raszuk et al., R., "BGP Optimal Route Reflection", July Raszuk et al., R., "BGP Optimal Route Reflection", July
2019. 2019, <https://www.ietf.org/id/draft-ietf-idr-bgp-optimal-
route-reflection-28.txt>.
[RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
Border Gateway Protocol 4 (BGP-4)", RFC 4271, Border Gateway Protocol 4 (BGP-4)", RFC 4271,
DOI 10.17487/RFC4271, January 2006, DOI 10.17487/RFC4271, January 2006,
<https://www.rfc-editor.org/info/rfc4271>. <https://www.rfc-editor.org/info/rfc4271>.
[RFC4456] Bates, T., Chen, E., and R. Chandra, "BGP Route [RFC4456] Bates, T., Chen, E., and R. Chandra, "BGP Route
Reflection: An Alternative to Full Mesh Internal BGP Reflection: An Alternative to Full Mesh Internal BGP
(IBGP)", RFC 4456, DOI 10.17487/RFC4456, April 2006, (IBGP)", RFC 4456, DOI 10.17487/RFC4456, April 2006,
<https://www.rfc-editor.org/info/rfc4456>. <https://www.rfc-editor.org/info/rfc4456>.
[RFC8099] Chen, H., Li, R., Retana, A., Yang, Y., and Z. Liu, "OSPF [RFC8099] Chen, H., Li, R., Retana, A., Yang, Y., and Z. Liu, "OSPF
Topology-Transparent Zone", RFC 8099, Topology-Transparent Zone", RFC 8099,
DOI 10.17487/RFC8099, February 2017, DOI 10.17487/RFC8099, February 2017,
<https://www.rfc-editor.org/info/rfc8099>. <https://www.rfc-editor.org/info/rfc8099>.
14.2. Normative References 16.2. Normative References
[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, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[RFC7775] Ginsberg, L., Litkowski, S., and S. Previdi, "IS-IS Route [RFC7775] Ginsberg, L., Litkowski, S., and S. Previdi, "IS-IS Route
Preference for Extended IP and IPv6 Reachability", Preference for Extended IP and IPv6 Reachability",
RFC 7775, DOI 10.17487/RFC7775, February 2016, RFC 7775, DOI 10.17487/RFC7775, February 2016,
<https://www.rfc-editor.org/info/rfc7775>. <https://www.rfc-editor.org/info/rfc7775>.
[RFC7981] Ginsberg, L., Previdi, S., and M. Chen, "IS-IS Extensions [RFC7981] Ginsberg, L., Previdi, S., and M. Chen, "IS-IS Extensions
for Advertising Router Information", RFC 7981, for Advertising Router Information", RFC 7981,
DOI 10.17487/RFC7981, October 2016, DOI 10.17487/RFC7981, October 2016,
<https://www.rfc-editor.org/info/rfc7981>. <https://www.rfc-editor.org/info/rfc7981>.
[RFC9012] Patel, K., Van de Velde, G., Sangli, S., and J. Scudder,
"The BGP Tunnel Encapsulation Attribute", RFC 9012,
DOI 10.17487/RFC9012, April 2021,
<https://www.rfc-editor.org/info/rfc9012>.
Authors' Addresses Authors' Addresses
Tony Przygienda Tony Przygienda
Juniper Juniper
1137 Innovation Way 1137 Innovation Way
Sunnyvale, CA Sunnyvale, CA
United States of America
USA
Email: prz@juniper.net Email: prz@juniper.net
Chris Bowers Chris Bowers
Juniper Juniper
1137 Innovation Way 1137 Innovation Way
Sunnyvale, CA Sunnyvale, CA
United States of America
USA
Email: cbowers@juniper.net Email: cbowers@juniper.net
Yiu Lee Yiu Lee
Comcast Comcast
1800 Bishops Gate Blvd 1800 Bishops Gate Blvd
Mount Laurel, NJ 08054 Mount Laurel, NJ 08054
US United States of America
Email: Yiu_Lee@comcast.com Email: Yiu_Lee@comcast.com
Alankar Sharma Alankar Sharma
Comcast Comcast
1800 Bishops Gate Blvd 1800 Bishops Gate Blvd
Mount Laurel, NJ 08054 Mount Laurel, NJ 08054
US United States of America
Email: Alankar_Sharma@comcast.com Email: Alankar_Sharma@comcast.com
Russ White Russ White
Juniper Juniper
1137 Innovation Way 1137 Innovation Way
Sunnyvale, CA Sunnyvale, CA
United States of America
USA
Email: russw@juniper.net Email: russw@juniper.net
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