BGP Classful Transport Planes
draft-kaliraj-idr-bgp-classful-transport-planes-00
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| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Authors | Kaliraj Vairavakkalai , Natrajan Venkataraman , Balaji Rajagopalan | ||
| Last updated | 2020-05-08 | ||
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draft-kaliraj-idr-bgp-classful-transport-planes-00
Network Working Group K. Vairavakkalai
Internet-Draft N. Venkataraman
Intended status: Standards Track B. Rajagopalan
Expires: November 8, 2020 Juniper Networks, Inc.
May 07, 2020
BGP Classful Transport Planes
draft-kaliraj-idr-bgp-classful-transport-planes-00
Abstract
This document specifies a mechanism, referred to as "service
mapping", to express association of overlay routes with underlay
routes using BGP. The document describes a framework for classifying
underlay routes into transport planes, and mapping service routes to
specific transport plane. It specifies BGP protocol procedures that
enable dissimination of such service mapping information that may
span across administrative domains. It makes it possible to
advertise multiple tunnels to the same destination.
A new BGP transport address family is defined for this purpose that
uses RFC-4364 technology and follows RFC-8277 NLRI encoding. This
new address family is called "Classful Transport".
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
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on November 8, 2020.
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Copyright Notice
Copyright (c) 2020 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
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described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Transport Class . . . . . . . . . . . . . . . . . . . . . . . 5
4. "Transport Class" Route Target Extended Community . . . . . . 6
5. Transport RIB . . . . . . . . . . . . . . . . . . . . . . . . 7
6. Transport Routing Instance . . . . . . . . . . . . . . . . . 7
7. Nexthop Resolution Scheme . . . . . . . . . . . . . . . . . . 7
8. BGP Classful Transport Family NLRI . . . . . . . . . . . . . 8
9. Comparison with other families using RFC-8277 encoding . . . 8
10. Protocol Procedures . . . . . . . . . . . . . . . . . . . . . 9
11. OAM considerations . . . . . . . . . . . . . . . . . . . . . 11
12. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
12.1. New BGP SAFI . . . . . . . . . . . . . . . . . . . . . . 12
12.2. New Format for BGP Extended Community . . . . . . . . . 12
13. Security Considerations . . . . . . . . . . . . . . . . . . . 12
14. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 12
15. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
15.1. Normative References . . . . . . . . . . . . . . . . . . 13
15.2. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
1. Introduction
To facilitate service mapping, the tunnels in a network can be
grouped by the purpose they serve into a "Transport Class". The
tunnels could be created using any signaling protocol, such as LDP,
RSVP, BGP-LU or SPRING. The tunnels could also use native IP or
IPv6, as long as the tunnels can carry MPLS payload. Tunnels may
exist between different pair of end points. Multiple tunnels may
exist between the same pair of end points.
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Thus, a Transport Class consists of tunnels created by many protocols
terminating in various nodes, each satisfying the properties of the
class. For example, a "Gold" transport class may consist of tunnels
that traverse the shortest path with fast re-route protection, a
"Silver" transport class may hold tunnels that traverse shortest
paths without protection, a "To NbrAS Foo" transport class may hold
tunnels that exit to neighboring AS Foo, and so on.
The extensions specified in this document can be used to create a BGP
transport tunnel that potentially spans domains, while preserving its
Transport Class. Examples of domain are Autonomous System (AS), or
IGP area. Within each domain, there is a second level underlay
tunnel used by BGP to cross the domain. The second level underlay
tunnels could be hetrogeneous: Each domain may use a different type
of tunnel, or use a differnet signaling protocol. A domain boundary
is demarcated by a rewrite of BGP nexthop to 'self' while re-
advertising tunnel routes in BGP. Examples of domain boundary are
inter-AS links and inter-region ABRs. The path uses MPLS label-
switching when crossing domain boundary and uses the native intra-AS
tunnel of the desired transport class when traversing within a
domain.
Overlay routes carry sufficient indication, in form of mapping
community, of the Transport Classes they should be encapsulated over.
A "route resolution" procedure on the ingress node selects from the
Transport Class an appropriate tunnel whose destination matches (LPM)
the nexthop of the overlay route. If the overlay route is carried in
BGP, the protocol nexthop (or, PNH) is generally carried as an
attribute of the route. The PNH of the overlay route is also
referred to as "service endpoint". The service endpoint may exist in
the same domain as the service ingress node or lie in a different
domain, adjacent or non-adjacent.
This document describes mechanisms to:
Model a "Transport Class" as "Transport RIB" on a router,
consisting of tunnel ingress routes of a certain class.
Enable service routes to resolve over an intended Transport Class
by using the corresponding Transport RIB for finding nexthop
reachability.
Advertise tunnel ingress routes in a Transport RIB via BGP without
any path hiding, using BGP VPN technology and Add-path. Such that
overlay routes in the receiving domains can also resolve over
tunnels of associated Transport Class.
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Provide a way for co-operating domains to reconcile between
independently administered extended community namespaces, and
interoperate between different transport signaling protocols in
each domain.
In this document we focus mainly on MPLS LSPs as transport tunnels,
but the mechanisms would work in similar manner for non-MPLS
transport tunnels too, provided the tunnel can carry MPLS payload.
2. Terminology
LSP: Label Switched Path
TE : Traffic Engineering
SN : Service Node
BN : Border Node
TN : Transport Node, P-router
BGP-VPN : VPNs built using RFC4364 mechanisms
RT : Route-Target extended community
RD : Route-Distinguisher
PNH : Protocol-Nexthop
LPM : Longest Prefix Match
Service Family : BGP address family used for advertising routes for
"data traffic", as opposed to tunnels
Transport Family : BGP address family used for advertising tunnels,
which are in turn used by service routes for resolution
Transport Tunnel : A tunnel over which a service may place traffic.
These tunnels can be GRE, UDP, LDP, RSVP, or SR-TE
Tunnel Domain : A domain of the network containing SN and BN, under a
single administrative control that has a tunnel between SN and BN.
An end-to-end tunnel spanning several adjacent tunnel domains can be
created by "stitching" them together using labels.
Transport Class : A group of transport tunnels offering the same type
of service.
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Transport Class RT : A Route-Target extended community used to
identify a specific Transport Class
Transport RIB : At the SN and BN, a Transport Class has an associted
Transport RIB that holds its tunnel routes.
Transport Plane : An end to end plane comprising of transport tunnels
belonging to same transport class. Tunnels of same transport class
are stitched together by BGP route readvertisements with nexthop-
self, to span across domain boundaries using Label-Swap forwarding
mechanism similar to Inter-AS option-b.
Mapping Community : Community on a service route, that maps it to
resolve over a Transport Class
3. Transport Class
A Transport Class is defined as a set of transport tunnels that share
certain characteristics useful for underlay selection.
On the wire, a transport class is represented as the Transport Class
RT, which is a new Route-Target extended community.
A Transport Class is configured at SN and BN, along with attributes
like RD and Route-Target. Creation of a Transport Class instantiates
the associated Transport RIB and a Transport routing instance to
contain them all.
The operator may configure a BN to classify a tunnel into an
appropriate Transport Class, which causes the tunnel's ingress routes
to be installed in the corresponding Transport RIB. These tunnel
routes may then be advertised into BGP.
Alternatively, a router receiving the transport routes in BGP with
appropriate signaling information can associate those ingress routes
to the appropriate Transport Class. E.g. for Classful Transport
family (SAFI TBD) routes, the Transport Class RT indicates the
Transport Class. For BGP-LU family(SAFI 4) routes, import policy
based on Communities or inter-AS source-peer may be used to place the
route in the desired Transport Class.
When the ingress route is received via SRTE [SRTE], which encodes the
Transport Class as an integer "Color" in the NLRI as
"Color:Endpoint", the Color can be mapped to a Transport Class during
import processing. The Color could map to a Transport Class Route-
Target that installs the ingress route for "Endpoint" in the
appropriate Transport RIB. The SRTE route when advertised out to BGP
speakers will then be advertised in Classful Transport family with
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Transport Class RT and a new label. The MPLS swap route thus
installed for the new label will pop the label and deliver
decapsulated-traffic into the path determined by SRTE route.
4. "Transport Class" Route Target Extended Community
This document defines a new type of Route Target, called "Transport
Class" Route Target Extended Community.
"Transport Class" Route Target extended community is a transitive
extended community EXT-COMM [RFC4360] of extended-type, with a new
Format (Type high = TBD) and SubType as 0x2 (Route Target).
This new Route Target Format has the following encoding:
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= TBD | SubType= 0x02 | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Transport Class |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
"Transport Class" Route Target Extended Community
Type: Type field contains value TBD.
SubType: Subtype field contain 0x2. This indicates 'Route Target'.
Transport Class: The least significant 32-bits of the value field
contain the "Transport Class" value, which is a 32-bit integer.
The remaining 2 octets after SubType field are Reserved, they must
be ignored on reception, and set to zero on transmission.
The "Transport class" Route Target Extended community follows the
mechanisms for VPN route leaking and RTC as sspecified in BGP-VPN
[RFC4364] and VPN-RTC [RFC4684]
The Transport Class Route Target Extended community is carried on
Classful Transport family routes, and allows associating them with
appropriate Transport RIBs at receiving BGP speakers.
Use of the Transport Class Route Target Extended community with a new
Type code avoids conflicts with any VPN Route Target assignments
already in use for service families.
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5. Transport RIB
A Transport RIB is a routing-only RIB that is not installed in
forwarding path. However, the routes in this RIB are used to resolve
reachability of overlay routes' PNH. Transport RIB is created when
the Transport Class it represents is configured.
Overlay routes that want to use a specific Transport Class confine
the scope of nexthop resolution to the set of routes contained in the
corresponding Transport RIB. This Transport RIB is the "Routing
Table" referred in Section 9.1.2.1 RFC4271 [1]
Routes in a Transport RIB are exported out in 'Classful Transport'
address family.
6. Transport Routing Instance
A BGP VPN routing instance that is a container for the Transport
RIBs. It imports, and exports routes in this RIB with Transport
Class RT. Tunnel destination addresses in this routing instance's
context come from the "provider namespace". This is different from
user VRFs for e.g., which contain prefixes in "customer namespace"
The Transport Routing instance uses the RD and RT configured for the
Transport Class.
7. Nexthop Resolution Scheme
An implementation may provide an option for the service route to
resolve over less preferred Transport Classes, should the resolution
over preferred, or "primary" Transport Class fail.
To accomplish this, the set of service routes may be associated with
a user-configured "resolution scheme", which consists of the primary
Transport Class, and an ordered list of fallback Transport Classes.
A community called as "Mapping Community" is configured for a
"resolution scheme". A Mapping community maps to exactly one
resolution scheme. A resolution scheme comprises of one primary
transport class and optionally one or more fallback transport
classes.
When a resolution scheme comprises of a primary Transport Class
without any fallback, the Transport Class RT associated with the
primary Transport Class is used as the Mapping Community.
A BGP route is associated with a resolution scheme during import
processing. The first community on the route that matches a mapping
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communiity of a locally configured resolution scheme is considered
the effective mapping community for the route. The resolution scheme
thus found is used when resolving the route's PNH. If a route
contains more than one mapping community, it indicates that the route
considers these multiple mapping communities as equivalent. So the
first community that maps to a resolution scheme is chosen.
A transport route received in BGP Classful Transport family should
use a resolution scheme that contains the primary Transport Class
without any fallback to best effort tunnels. The primary Transport
Class is identified by the Transport Class RT carried on the route.
Thus Transport Class RT serves as the Mapping Community for Classful
Transport routes.
8. BGP Classful Transport Family NLRI
The Classful Transport family will use the existing AFI of IPv4 or
IPv6, and a new SAFI TBD "Classful Transport" that will apply to both
IPv4 and IPv6 AFIs.
The "Classful Transport" SAFI NLRI itself is encoded as specified in
https://tools.ietf.org/html/rfc8277#section-2 [RFC8277].
When AFI is IPv4 the "Prefix" portion of Classful Transport family
NLRI consists of an 8-byte RD followed by an IPv4 prefix. When AFI
is IPv6 the "Prefix" consists of an 8-byte RD followed by an IPv6
prefix.
Attributes on a Classful Transport route include the Transport Class
Route-Target extended community, which is used to leak the route into
the right Transport RIBs on SNs and BNs in the network.
9. Comparison with other families using RFC-8277 encoding
SAFI 128 (Inet-VPN) is a RF8277 encoded family that carries service
prefixes in the NLRI, where the prefixes come from the customer
namespaces, and are contexualized into separate user virtual service
RIBs called VRFs, using RFC4364 procedures.
SAFI 4 (BGP-LU) is a RFC8277 encoded family that carries transport
prefixes in the NLRI, where the prefixes come from the provider
namespace.
SAFI TBD (Classful Transport) is a RFC8277 encoded family that
carries transport prefixes in the NLRI, where the prefixes come from
the provider namespace, but are contexualized into separate Transport
RIBs, using RFC4364 procedures.
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It is worth noting that SAFI 128 has been used to carry transport
prefixes in "L3VPN Inter-AS Carrier's carrier" scenario, where BGP-
LU/LDP prefixes in CsC VRF are advertised in SAFI 128 to the remote-
end baby carrier.
In this document a new AFI/SAFI is used instead of reusing SAFI 128
to carry these transport routes, because it is operationally
advantageous to segregate transport and service prefixes into
separate address families, RIBs. E.g. It allows to safely enable
"per-prefix" label allocation scheme for Classful Transport prefixes
without affecting SAFI 128 service prefixes which may have huge
scale. "per prefix" label allocation scheme keeps the routing churn
local during topology changes. A new family also facilitates having
a different readvertisement path of the transport family routes in a
network than the service route readvertisement path. viz. Service
routes (Inet-VPN) are exchanged over an EBGP multihop sessions
between Autonomous systems with nexthop unchanged; whereas Classful
Transport routes are readvertised over EBGP single hop sessions with
"nexthop-self" rewrite over inter-AS links.
The Classful Transport family is similar in vein to BGP-LU, in that
it carries transport prefixes. The only difference is, it also
carries in Route Target an indication of which Transport Class the
transport prefix belongs to, and uses RD to disambiguate multiple
instances of the same transport prefix in a BGP Update.
10. Protocol Procedures
This section summarizes the procedures followed by various nodes
speaking Classful Transport family
Preparing the network for deploying Classful Transport planes
Operator decides on the Transport Classes that exist in the
network, and allocates a Route-Target to identify each Transport
Class.
Operator configures Transport Classes on the SNs and BNs in the
network with unique Route-Distinguishers and Route-Targets.
Implementations may provide automatic generation and assignment of
RD, RT values for a transport routing instance; they should also
provide a way to manually override the automatic mechanism, in
order to deal with any conflicts that may arise with existing RD,
RT values in the different network domains participating in a
deployment.
Origination of Classful Transport route:
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At the ingress node of the tunnel's home domain, the tunneling
protocols install routes in the Transport RIB associated with the
Transport Class the tunnel belongs to. The ingress node then
advertises this tunnel route into BGP as a Classful Transport
route with NLRI RD:TunnelEndpoint, attaching a Route-Target that
identifies the Transport Class.
Alternatively, the egress node of the tunnel i.e. the tunnel
endpoint can originate the BGP Classful Transport route, with NLRI
RD:TunnelEndpoint and PNH TunnelEndpoint, which will resolve over
the tunnel route at the ingress node. When the tunnel is up, the
Classful Transport BGP route will become usable and get re-
advertised.
Unique RD is used by the originator of a Classful Transport route
to disambiguate the multiple BGP advertisements for a transport
end point.
Ingress node receiving Classful Transport route
On receiving a BGP Classful Transport route with a PNH that is not
directly connected, e.g. an IBGP-route, a mapping community on the
route (the Transport Class RT) indicates which Transport Class
this route maps to. The routes in the associated Transport RIB
are used to resolve the received PNH. If there does not exist a
route in the Transport RIB matching the PNH, the Classful
Transport route is considered unusable, and MUST NOT be re-
advertised further.
Border node readvertising Classful Transport route with nexthop self:
The BN allocates an MPLS label to advertise upstream in Classful
Transport NLRI. The BN also installs an MPLS swap-route for that
label that swaps the incoming label with a label received from the
downstream BGP speaker, or pops the incoming label. And then
pushes received traffic to the transport tunnel or direct
interface that the Classful Transport route's PNH resolved over.
Border node receiving Classful Transport route on EBGP :
If the route is received with PNH that is known to be directly
connected, e.g. EBGP single-hop peering address, the directly
connected interface is checked for MPLS forwarding capability. No
other nexthop resolution process is performed, as the inter-AS
link can be used for any Transport Class.
If the inter-AS links should honor Transport Class, then the BN
should follow procedures of an Ingress node described above, and
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perform nexthop resolution process. The interface routes should
be installed in the Transport RIB belonging to the associated
Transport Class.
Avoiding path-hiding through Route Reflectors
When multiple BNs exist that advertise a RDn:PEn prefix to RRs,
the RRs may hide all but one of the BNs, unless ADDPATH [RFC7911]
is used for the Classful Transport family. This is similar to
L3VPN option-B scenarios. Hence ADDPATH should be used for
Classful Transport family, to avoid path-hiding through RRs.
Ingress node receiving service route with mapping community
Service routes received with mapping community resolve using
Transport RIBs determined by the resolution scheme. If the
resolution process does not find an usable Classful Transport
route or tunnel route in any of the Transport RIBs, the service
route MUST be considered unusable for forwarding purpose.
Coordinating between domains using different community namespaces.
Domains not agreeing on RT, RD, Mapping-community values because
of independently administered community namespaces may deploy
mechanisms to map and rewrite the Route-target values on domain
boundaries, using per ASBR import policies. This is no different
than any other BGP VPN family. Mechanisms employed in inter-AS
VPN deployments may be used with the Classful Transport family
also.
The resolution schemes should allow association with multiple
mapping communities. This also helps with renumbering, network
mergers, or transitions.
Though RD can also be rewritten on domain boundaries, deploying
unique RDs is strongly recommended, because it helps in trouble
shooting by uniquely identifying originator of a route, and avoids
path-hiding.
This document defines a new format of Route-Target extended-
community to carry Transport Class, this avoids collision with
regular Route Target namespace used by service routes.
11. OAM considerations
TBD
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12. IANA Considerations
This document makes following requests of IANA.
12.1. New BGP SAFI
New BGP SAFI code for "Classful Transport". Value TBD.
This will be used to create new AFI,SAFI pairs for IPv4, IPv6
Classful Transport families. viz:
o "Inet, Classful Transport". AFI/SAFI = "1/TBD" for carrying IPv4
Classful Transport prefixes.
o "Inet6, Classful Transport". AFI/SAFI = "2/TBD" for carrying IPv6
Classful Transport prefixes.
12.2. New Format for BGP Extended Community
Please assign a new Format (Type high = TBD) of extended community
EXT-COMM [RFC4360] called "Transport Class".
It is a transitive extended community. This document uses this new
Format with subtype 0x2 (route target) extended community.
The Route Target thus formed is called "Transport Class" route target
extended community.
13. Security Considerations
Mechanisms described in this document carry Transport routes in a new
BGP address family. That minimizes possibility of these routes
leaking outside the expected domain or mixing with service routes.
When redistributing between SAFI 4 and SAFI TBD Classful Transport
routes, there is a possibility of SAFI 4 routes mixing with SAFI 1
service routes. To avoid such scenarios, it is recommended that
implementations support keeping SAFI 4 routes in a separate transport
RIB, distinct from service RIB that contain SAFI 1 service routes.
14. Acknowledgements
The authors thank Jeff Haas, John Scudder, Navaneetha Krishnan, Ravi
M R, Chandrasekar Ramachandran, Shradha Hegde, Richard Roberts,
Krzysztof Szarkowicz, John E Drake, Srihari Sangli, Vijay Kestur,
Santosh Kolenchery for the valuable discussions.
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The decision to not reuse SAFI 128 and create a new address-family to
carry these transport-routes was based on suggestion made by Richard
Roberts and Krzysztof Szarkowicz.
15. References
15.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
Border Gateway Protocol 4 (BGP-4)", RFC 4271,
DOI 10.17487/RFC4271, January 2006,
<https://www.rfc-editor.org/info/rfc4271>.
[RFC4360] Sangli, S., Tappan, D., and Y. Rekhter, "BGP Extended
Communities Attribute", RFC 4360, DOI 10.17487/RFC4360,
February 2006, <https://www.rfc-editor.org/info/rfc4360>.
[RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private
Networks (VPNs)", RFC 4364, DOI 10.17487/RFC4364, February
2006, <https://www.rfc-editor.org/info/rfc4364>.
[RFC4684] Marques, P., Bonica, R., Fang, L., Martini, L., Raszuk,
R., Patel, K., and J. Guichard, "Constrained Route
Distribution for Border Gateway Protocol/MultiProtocol
Label Switching (BGP/MPLS) Internet Protocol (IP) Virtual
Private Networks (VPNs)", RFC 4684, DOI 10.17487/RFC4684,
November 2006, <https://www.rfc-editor.org/info/rfc4684>.
[RFC7911] Walton, D., Retana, A., Chen, E., and J. Scudder,
"Advertisement of Multiple Paths in BGP", RFC 7911,
DOI 10.17487/RFC7911, July 2016,
<https://www.rfc-editor.org/info/rfc7911>.
[RFC8277] Rosen, E., "Using BGP to Bind MPLS Labels to Address
Prefixes", RFC 8277, DOI 10.17487/RFC8277, October 2017,
<https://www.rfc-editor.org/info/rfc8277>.
[SRTE] Previdi, S., Ed., "Advertising Segment Routing Policies in
BGP", 11 2019, <https://tools.ietf.org/html/draft-ietf-
idr-segment-routing-te-policy-08>.
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15.2. URIs
[1] https://www.rfc-editor.org/rfc/rfc4271#section-9.1.2.1
Authors' Addresses
Kaliraj Vairavakkalai
Juniper Networks, Inc.
1133 Innovation Way,
Sunnyvale, CA 94089
US
Email: kaliraj@juniper.net
Natarajan Venkataraman
Juniper Networks, Inc.
1133 Innovation Way,
Sunnyvale, CA 94089
US
Email: natv@juniper.net
Balaji Rajagopalan
Juniper Networks, Inc.
Electra, Exora Business Park~Marathahalli - Sarjapur Outer
Ring Road,
Bangalore, KA 560103
India
Email: balajir@juniper.net
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