Internet DRAFT - draft-ssangli-bess-bgp-vpn-srm6
draft-ssangli-bess-bgp-vpn-srm6
IDR S. Sangli
Internet-Draft R. Bonica
Intended status: Standards Track Juniper Networks Inc.
Expires: March 11, 2021 September 07, 2020
BGP based Virtual Private Network (VPN) Services over SRm6 enabled IPv6
networks
draft-ssangli-bess-bgp-vpn-srm6-02
Abstract
This document defines BGP protocol extensions for encoding and
carrying SRm6 Tunnel Payload Forwarding information (TPF) to support
Virtual Private Network services. This is applicable when the VPN
services are offered in a SRm6 enabled IPv6 network such that the VPN
payload is transported over IPv6. The Tunnel Payload Information is
encoded in the IPv6 Destination Option Header in the IPv6 data
packets.
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
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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 March 11, 2021.
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
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
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include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Requirements Language . . . . . . . . . . . . . . . . . . . . 3
3. Per-Path Service Instruction Information . . . . . . . . . . 3
4. Usage of Tunnel Encapsulation Attribute . . . . . . . . . . . 4
5. Procedures for Egress BGP Speaker . . . . . . . . . . . . . . 6
6. Procedures for Ingress BGP Speaker . . . . . . . . . . . . . 7
7. BGP Nexthop and Tunnel Endpoint address handling
procedures . . . . . . . . . . . . . . . . . . . . . . . . . 7
8. BGP based L3 VPN services over IPv6 . . . . . . . . . . . . . 8
8.1. IPv4 VPN on SRm6 enabled IPv6 Core . . . . . . . . . . . 8
8.2. IPv6 VPN on SRm6 enabled IPv6 Core . . . . . . . . . . . 8
8.3. IPv4 Global Routes on SRm6 enabled IPv6 Core . . . . . . 9
9. BGP based Ethernet VPN services over IPv6 . . . . . . . . . . 9
9.1. Ethernet Per ES Auto-Discovery (A-D) route . . . . . . . 10
9.2. Ethernet per EVI Auto-Discovery (A-D) route . . . . . . . 10
9.3. MAC/IP Advertisement route . . . . . . . . . . . . . . . 11
9.4. Inclusive Multicast Ethernet Route . . . . . . . . . . . 11
9.5. IP Prefix Route . . . . . . . . . . . . . . . . . . . . . 12
10. Deployment Considerations . . . . . . . . . . . . . . . . . . 12
11. Backward Compatibility . . . . . . . . . . . . . . . . . . . 13
12. Security Considerations . . . . . . . . . . . . . . . . . . . 14
13. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
14. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
15. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
15.1. Normative References . . . . . . . . . . . . . . . . . . 14
15.2. Informative References . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
Virtual Private Network (VPN) technologies allow network providers to
emulate private networks with shared infrastructure. For example,
assume that a set of red sites, set of blue sites and a set of green
sites connect to a provider network. Furthermore, assume that red
sites and blue sites wish to interconnect, exchange packets.
However, the green sites wish to communicate with green sites only.
The provider should allow its infrastructure network to scale to both
the requirements without having to create multiple parallel network
infrastructures. The IETF has standardized many VPN technologies
viz. Layer 3 VPN (L3VPN) [RFC4364], Layer 2 VPN (L2VPN) [RFC6624],
Virtual Private LAN Service (VPLS) [RFC4761], [RFC4762], Ethernet VPN
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(EVPN) [RFC7432], Pseudowires [RFC8077] to enable Layer 3 and Layer 2
VPN services.
The aforementioned technologies leverage MPLS network architecture :
o to establish a MPLS tunnel from ingress PE to egress PE, thus
making all P routers agnostic of VPN state.
o to provide demultiplexing abstraction in the tunnelled packet so
the payload packet can be forwarded at the egress router based on
Routing table and/or interface.
In pure IPv6 deployments where there may be non-MPLS capable routers,
it would be desirable to have alternate mechanism to provide VPN
connectivity. This document describes BGP extensions and procedures
applicable for SRm6 enabled IPv6 networks, to provide VPN services
over BGP.
2. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
3. Per-Path Service Instruction Information
A SRm6 [I-D.bonica-spring-sr-mapped-six] segment provides
unidirectional connectivity from an ingress node to an egress node.
A SRm6 path contains one or more such segments. SRm6 introduces the
concept of Per-Segment Service Instruction and Per-Path Service
Instruction. These instructions describe the additional packet
processing performed on a node. The Per-Segment Service Instruction
is executed on the segment egress node while the Per-Path Service
Instruction is executed on the path egress node. The SR Path egress
node advertises the service prefix reachability information to SR
Path ingress node via Multi-Protocol extensions in BGP [RFC4760].
For providing VPN services, aforementioned BGP extensions rely on
MPLS architecture [RFC3031]. The BGP extensions specify the new
encoding for Network Layer Reachability Information (NLRI) to include
the MPLS VPN labels [RFC8277]. Such a MPLS VPN label is associated
with a forwarding decision in the VPN Routing Instance on the egress
BGP Router. The ingress BGP router will push the VPN label on the
data packet destined to the egress BGP router. The transport tunnel
from ingress router to egress router can be MPLS or GRE or L2TPv3,
but inner payload is a MPLS packet as described in [RFC4023],
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[RFC4817], [RFC7510]. The intermediate routers do not process the
VPN label [a.k.a.] embedded label as described in
[I-D.ietf-idr-tunnel-encaps].
To provide BGP based VPN services on a non-MPLS IPv6 networks, it
would be beneficial to retain the benefits of BGP protocol extensions
while leveraging the benefits of IPv6 [RFC8200].
[I-D.bonica-6man-vpn-dest-opt] describes SRm6 paths as programmable
with Tunnel Payload Forwarding information (TPF) that determine how
egress nodes process SRm6 payloads. The TPF information is carried
in the Tunnel Payload Forwarding Option encoded in the IPv6
Destination Option Header [RFC8200].
The Tunnel Payload Forwarding (TPF) information is defined as
follows:
o 32 bit quantity.
The TPF information have node-local significance and is assigned by
the egress BGP router. The value of zero is reserved. The TPF
information will serve 2 purposes.
o It MUST uniquely identify the VPN Routing Instance for L3VPN or
identify an Ethernet Segment for EVPN or identify a leaf property
for EVPN TREE upon which forwarding decision can be taken.
o It MAY provide information for special processing before the
packet is forwarded.
The structure of TPF information will be updated in the next version
of this document.
The encoding of the Tunnel Payload Forwarding information for VPNs is
described in Section 8 and Section 9.
4. Usage of Tunnel Encapsulation Attribute
This document defines a new Tunnel type : SRm6. The format is as per
below.
o Tunnel Type (2 Octets) : To be assigned
o Tunnel Length (2 Octets) : 1
o Value : List of Sub-TLVs
[I-D.ietf-idr-tunnel-encaps] defines many sub-TLVs for the tunnels.
The encoding for them are as follows:
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o Tunnel Endpoint Sub-TLV : As per [I-D.ietf-idr-tunnel-encaps]
o Encapsulation Sub-TLV : Not needed.
o IPv4 DS Field Sub-TLV : Not needed.
o UDP Destination Port Sub-TLV : Not needed.
o Protocol Type Sub-TLV : As per [I-D.ietf-idr-tunnel-encaps].
o Color Sub-TLV : As per [I-D.ietf-idr-tunnel-encaps].
o Embedded Label Handling Sub-TLV : 3.
o MPLS Label Stack Sub-TLV : Not needed.
o Prefix SID Sub-TLV : Not Needed.
The Tunnel Encapsulation Attribute is a an Optional Transitive
attribute as described in [I-D.ietf-idr-tunnel-encaps]. This
attribute with SRm6 tunnel type MUST be present in the BGP update
carrying the Network Layer Reachability Information encoded with the
TPF information. This document refers to the NLRI that is associated
with SRm6 Tunnel Encapsulation attribute as SRm6_NLRI. The document
[I-D.ietf-idr-tunnel-encaps] defines the encoding for sub-TLV as
follows.
o Sub-TLV Type : 1 octet
o Sub-TLV Length : 1 or 2 octets
o Sub-TLV Value : defined per Sub-TLV as per below.
The Tunnel Endpoint Sub-TLV can specify the IPv6 address of the
egress router as the final destination address of SRm6 packet which
is also referred to as SR Path destination address. The sub-fields
on this sub-TLV is encoded as below.
o Autonomous System Number : AS number of the IPv6 SR domain.
o Address Family : 2 (refers to IPv6).
o Address : IPv6 address of the egress interface present in SRm6
domain.
The Value field may be set to 0 which indicates that next hop value
in the NLRI should be chosen for the SRm6 Path destination address.
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The Embedded Label Handling Sub-TLV describes how the label field in
the NLRI should be interpreted.
o Value : MUST be set to 3.
The [I-D.ietf-idr-tunnel-encaps] specifies only 2 values. While the
value 1 refers to label field as MPLS embedded label that is carried
at the top of the label stack of the MPLS payload packet, the value 2
refers to label field to be either ignored or carried in the virtual
network field of the encapsulation header.
This document defines another behavior for the label field. The
value 3 will indicate that value in the label field MUST be inserted
in the Destination Options Header of the IPv6 Tunnel header.
The Tunnel Encapsulation attribute can carry one or more Tunnel
types. The local policy on the ingress router can determine which
Tunnel type to be used for the NLRI. The Tunnel Endpoint address
MUST be set only by the egress BGP router that is the endpoint of the
SRm6 path.
5. Procedures for Egress BGP Speaker
The TPF information instructs the egress router to de-encapsulate the
packet and forward the newly exposed payload inner packet through the
specified interface or forward using the specified Routing Instance.
The TPF information described in Section 3 will be assigned by the
egress BGP Router.
When the egress BGP Speaker advertises the NLRI, it will include the
TPF information in the encoding described in Section 8 and Section 9.
The egress BGP Speaker MUST include the Tunnel Encapsulation
Attribute with Route type SRm6 as described in Section 4 in such BGP
updates.
By tagging the BGP update with Tunnel Encapsulation attribute of SRm6
type, the BGP Speaker informs how the SRm6_NLRI should be decoded and
processed by the receiving BGP Speaker.
Via the Remote Tunnel Endpoint Sub-TLV encoding, the egress BGP
router may specify the SRm6 Path Destination Address. The Protocol
type Sub-TLV and the Color Sub-TLV may be used by the egress BGP
router to influence the payload packets to be put on SRm6 path. The
Embedded Label Handling Sub-TLV MUST be set to 3 to inform that the
label field MUST be used to form the TPF option that is inserted in
the Destination Options Header at the ingress router as described in
[I-D.bonica-6man-vpn-dest-opt].
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A single TPF information may be associated with all the prefixes in a
Routing Instance or a unique TPF information may be associated for
each prefix in the Routing Instance. Similarly, a TPF information
may be assigned to identify an Ethernet segment or leaf AC property
by EVPN. The choice is left to the Network Operator and is outside
the scope of this document.
6. Procedures for Ingress BGP Speaker
Upon receiving a BGP update, the receiving BGP Speaker will look for
Tunnel Encapsulation attribute. If the tunnel type carried in the
Tunnel Encapsulation attribute is SRm6, the BGP updates is said to be
carrying the SRm6_NLRI and the Label field in the Network Layer
Reachability Information is treated as Tunnel Payload Forwarding
information (TPF).
The tuple (TPF information, Prefix) is programmed in the forwarding
infrastructure of the router. The manner in which this tuple is
stored in the router is outside the scope of this document. If SRm6
has been enabled on the router, such a tuple SHOULD be used for
encoding the Destination Options Header as described in
[I-D.bonica-6man-vpn-dest-opt].
The [I-D.ietf-idr-tunnel-encaps] describes how Tunnel Endpoint Sub-
TLV has to be processed. It also describes the usage of the Protocol
type Sub-TLV and the Color Sub-TLV. This may be used by the ingress
BGP router to select the payload packets that should be put on SRm6
path.
The Embedded Label Handling Sub-TLV value that is set to 3 indicates
that ingress BGP router to use the value of label field to construct
the Tunnel Payload Forwarding Option that is inserted in the
Destination Options Header of the Tunnel IPv6 packet.
7. BGP Nexthop and Tunnel Endpoint address handling procedures
The BGP Nexthop attribute handling procedures are described in
[RFC4271] while [RFC4760] describe the handling procedures for the
Nexthop field in the MP_REACH attribute. The target="I-D.ietf-idr-
tunnel-encaps"/> describes the Tunnel Endpoint sub-TLV in the Tunnel
Encapsulation Attribute as the next hop address to which the prefix
should be forwarded to. If a BGP update has such a Tunnel
Encapsulation Attribute it prescribes that the Tunnel Endpoint Sub-
TLV if non-zero, MUST be used as the next hop to send the packet to.
There may be instances where the BGP update carrying the SRm6 NLRI
will cross Autonomous boundary. The BGP update with SRm6 NLRI MUST
always carry the Tunnel Encapsulation Attribute. If any router along
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the path wishes to change the Tunnel Endpoint Sub-TLV next hop
address, it MUST also update the TPF information field of the The BGP
update carrying the SRm6 NLRI.
It should be noted that router that modifies the Tunnel Endpoint sub-
TLV of the Tunnel Encapsulation attribute present in the SRm6 update
must be able to stitch the egress tunnel and ingress tunnel.
8. BGP based L3 VPN services over IPv6
The Egress and Ingress BGP speakers form a BGP peering session to
exchange a set of prefixes described in [RFC4271] and Multi-Protocol
extensions [RFC4760]. The BGP Router capable of SRm6 that is enabled
to carry L3 VPN services over IPv6 networks should follow the
procedures mentioned in Section 5 and Section 6. The manner in which
a BGP Router is configured for SRm6 underlay and L3 VPN overlay is
outside the scope of this document.
8.1. IPv4 VPN on SRm6 enabled IPv6 Core
The IPv4 L3 VPN over IPv6 is defined in [RFC5549]. The MP_REACH NLRI
and Tunnel Encapsulation attribute encoding is as per below:
o AFI : 1; SAFI : 128
o Length of the Next Hop : 16 (or 32 if Link Local)
o Network address of the Next Hop : IPv6 address of the egress BGP
Router
o NLRI : IPv4-VPN routes
o Label : Low order 24 bits of Tunnel Payload Forwarding (TPF)
information
o Tunnel Encapsulation Path Attribute : SRm6 Type as described in
Section 4
The TPF information is associated with VPN Routing Instance on the
Egress PE. The Tunnel Encapsulation attribute with SRm6 type MUST be
appended to the Path attributes associated with the NLRI.
8.2. IPv6 VPN on SRm6 enabled IPv6 Core
The IPv6 L3 VPN over IPv6 is defined in [RFC4659]. The MP_REACH NLRI
and Tunnel Encapsulation attribute encoding is as per below:
o AFI : 2; SAFI : 128
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o Length of the Next Hop : 16 (or 32 if Link Local)
o Network address of the Next Hop : IPv6 address of the egress BGP
Router
o NLRI : IPv6-VPN routes
o Label : Low order 24 bits of Tunnel Payload Forwarding (TPF)
information
o Tunnel Encapsulation Path Attribute : SRm6 Type as described in
(Section 4)
The TPF information is associated with VPN Routing Instance on the
Egress PE. The Tunnel Encapsulation attribute with SRm6 type MUST be
appended to the Path attribute associated with the NLRI.
8.3. IPv4 Global Routes on SRm6 enabled IPv6 Core
The IPv4 L3 VPN over IPv6 is defined in [RFC5549]. The MP_REACH NLRI
and Tunnel Encapsulation attribute encoding is per below:
o AFI : 1; SAFI : 1
o Length of the Next Hop : 16 (or 32 if Link Local)
o Network address of the Next Hop : IPv6 address of the egress BGP
Router
o NLRI : IPv4 routes
o Label : Low order 24 bits of Tunnel Payload Forwarding (TPF)
information
o Tunnel Encapsulation Path Attribute : SRm6 Type as described in
(Section 4)
The TPF information is associated with VPN Routing Instance on the
Egress PE. The Tunnel Encapsulation attribute with SRm6 type MUST be
appended to the Path attribute associated with the NLRI.
9. BGP based Ethernet VPN services over IPv6
The [RFC7432] describes the BGP extensions for carrying the Ethernet
Virtual Private Network Overlay on MPLS network. It defines 4 types
of EVPN NLRI. This document specifies changes to certain fields for
those NLRIs.
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o Ethernet Auto-Discovery (A-D) route
o MAC/IP Advertisement route
o Inclusive Multicast Ethernet Tag route
o IP Prefix route
9.1. Ethernet Per ES Auto-Discovery (A-D) route
The MP_REACH and MP_UNREACH attributes will carry this route in the
NLRI encoding described in [RFC7432]. In addition to Tunnel
Encapsulation attribute encoding, this document recommends to follow
the [RFC7432] encoding except the following. For MPLS label carried
in the Ethernet A-D per ESI route:
o MPLS label : Per [RFC7432], it is set to zero.
o Tunnel Encapsulation Path Attribute : SRm6 Type as described in
(Section 4)
The MPLS label field is not part of the route but treated as route
attribute. For procedures and usage of this route, refer to
[RFC7432]. The Tunnel Encapsulation attribute with SRm6 type MUST be
appended to the Path attribute associated with the NLRI.
An EVPN Ethernet per ES A-D route is usually signaled together with
an ESI label extended community. For ESI Label carried in the ESI
label extended community:
o ESI Label: Low order 24 bits of the Tunnel Payload Forwarding
(TPF) information
The TPF information is used to identify an Ethernet segment attached
to the BGP PE for EVPN.
9.2. Ethernet per EVI Auto-Discovery (A-D) route
The MP_REACH and MP_UNREACH attributes will carry this route in the
NLRI encoding described in [RFC7432]. In addition to Tunnel
Encapsulation attribute encoding, this document recommends to follow
the [RFC7432] encoding except the following:
o MPLS label : Low order 24 bits of Tunnel Payload Forwarding (TPF)
information
o Tunnel Encapsulation Path Attribute : SRm6 Type as described in
(Section 4)
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The MPLS label field is not part of the route but treated as route
attribute. For procedures and usage of this route, refer to
[RFC7432]. The Tunnel Encapsulation attribute with SRm6 type MUST be
appended to the Path attribute associated with the NLRI.
In addition, for EVPN E-tree service, this route may be signaled
together with an E-Tree Extended Community as it is specified in
[RFC8317]. For the leaf label carried in the E-Tree Extended
Community:
o Leaf Label: Low order 24 bits of the Tunnel Payload Forwarding
(TPF) information
In case of EVPN E-tree service, the TPF information carried in the
E-Tree extended community is used to signal a leaf AC property.
In the data plane, this TPF information specified in the Destination
Option header is used by an egress router to identify that a data
packet is ingressed from a leaf AC such that appropriate forwarding
decision can be made.
9.3. MAC/IP Advertisement route
The MP_REACH and MP_UNREACH attributes will carry this route in the
NLRI encoding described in [RFC7432]. In addition to Tunnel
Encapsulation attribute encoding, this document recommends to follow
the [RFC7432] encoding except the following.
o MPLS label1 : Low order 24 bits of the Tunnel Payload Forwarding
(TPF) information1
o MPLS label2 : Low order 24 bits of the Tunnel Payload Forwarding
(TPF) information2
o Tunnel Encapsulation Path Attribute : SRm6 Type as described in
(Section 4)
The MPLS label field is not part of the route but treated as route
attribute. For procedures and usage of this route, refer to
[RFC7432]. The Tunnel Encapsulation attribute with SRm6 type MUST be
appended to the Path attribute associated with the NLRI.
9.4. Inclusive Multicast Ethernet Route
The MP_REACH and MP_UNREACH attributes will carry this route in the
NLRI encoding described in [RFC7432]. In addition to Tunnel
Encapsulation attribute encoding, this document recommends to follow
the [RFC7432] encoding except the following.
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o If MPLS label field in the PMSI Tunnel Attributed is non-zero, it
is set to Low order 24 bits of the Tunnel Payload Forwarding (TPF)
information.
o Tunnel Encapsulation Path Attribute : SRm6 Type as described in
(Section 4)
The Tunnel Encapsulation attribute with SRm6 type MUST be appended to
the Path attribute associated with the NLRI.
9.5. IP Prefix Route
The MP_REACH and MP_UNREACH attributes will carry this route in the
NLRI encoding described in [I-D.ietf-bess-evpn-prefix-advertisement].
In addition to Tunnel Encapsulation attribute encoding, this document
recommends the following change:
o MPLS label: if it is non-zero, it is set to Low order 24 bits of
the Tunnel Payload Forwarding (TPF) information.
o Tunnel Encapsulation Path Attribute : SRm6 Type as described in
(Section 4)
The MPLS label field is not part of the route but treated as route
attribute. For procedures and usage of this route, refer to
[I-D.ietf-bess-evpn-prefix-advertisement]. The Tunnel Encapsulation
attribute with SRm6 type MUST be appended to the Path attribute
associated with the NLRI.
10. Deployment Considerations
This document proposes to reuse the NLRI encoding for BGP L3VPN and
EVPN Network Layer Routing Information. However, care should be
taken when BGP VPN overlay services are enabled on SRm6 underlay such
that Tunnel Encapsulation Path attribute with SRm6 type MUST be
appended. When a BGP router advertises SRm6_NLRI, it MUST NOT remove
the Tunnel Encapsulation Path attribute.
The SRm6 underlay is similar to other "tunnel" technologies viz MPLS,
GRE, IP-in-IP, L2TPv3. The egress and ingress BGP routers can be
connected via one or more such underlay technologies. A BGP speaker
can advertise the VPN NLRI with the nexthop reachable via one or more
such underlay paths. Each such mechanism can co-exist together as
ships-in-night. However, when SRm6_NLRI is advertised by a egress
BGP speaker and received by an ingress BGP speaker, they MUST follow
the procedures mentioned in this document.
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For migrating a BGP router to SRm6 the following procedures can be
followed.
o Operator will enable SRm6 underlay on the ingress and egress
routers identifying the SRm6 path from ingress router's interface
to egress router's interface. The way to configure the ingress
and egress routers are outside the scope of this document.
o SRm6 enabled ingress BGP router will setup the additional
information in the forwarding table such that it can append an
IPv6 tunnel header and encode the TPF Option in the Destination
Options Header.
o SRm6 enabled egress BGP router will setup the additional
information in the forwarding table such that TPF information can
be used to lookup to find the Routing Instance and make the
forwarding decision.
o Operator will enable BGP VPN overlay over SRm6 underlay on ingress
router. This means that ingress router will start looking for
SRm6_NLRI in the BGP updates. The way to enable the BGP VPN
overlay over SRm6 underlay is outside the scope of this document.
o The operator will enable BGP VPN overlay over SRm6 underlay on
egress router. With this, the egress router will create TPF
information and associate it with Routing Instances. It then
advertises the SRm6_NLRIs to the ingress BGP router.
o The ingress router will interpret the SRm6_NLRIs and use TPF
information and follow the procedures in
[I-D.bonica-spring-sr-mapped-six] to encode the Destination
Options Header to forward the data packet.
o Now that SRm6 path is setup between ingress and egress BGP
routers, on the egress BGP router the Operator can migrate the
Routing Instances from MPLS VPN set of Instances to SRm6 enabled
set of Instances. The way to configure Routing Instances to
achieve the above is outside the scope of this document.
11. Backward Compatibility
The extension proposed in this document is backward compatible with
procedures described for BGP enabled services.
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12. Security Considerations
This document does not introduce any new security considerations
beyond those already specified in [RFC4271], [RFC8277] and
[I-D.ietf-idr-tunnel-encaps].
13. IANA Considerations
IANA is requested to assign a code point for SRm6 Route Type for BGP
Tunnel Encapsulation Path Attribute from BGP Tunnel Encapsulation
Attribute Tunnel Types Registry.
14. Acknowledgements
The authors would like to thank Jeff Haas, Wen Lin and Shraddha Hegde
for careful review and suggestions.
15. References
15.1. Normative References
[I-D.bonica-6man-vpn-dest-opt]
Bonica, R., Kamite, Y., Jalil, L., Zhou, Y., and G. Chen,
"The IPv6 Tunnel Payload Forwarding (TPF) Option", draft-
bonica-6man-vpn-dest-opt-13 (work in progress), August
2020.
[I-D.bonica-spring-sr-mapped-six]
Bonica, R., Hegde, S., Kamite, Y., Alston, A., Henriques,
D., Jalil, L., Halpern, J., Linkova, J., and G. Chen,
"Segment Routing Mapped To IPv6 (SRm6)", draft-bonica-
spring-sr-mapped-six-01 (work in progress), April 2020.
[I-D.ietf-bess-evpn-prefix-advertisement]
Rabadan, J., Henderickx, W., Drake, J., Lin, W., and A.
Sajassi, "IP Prefix Advertisement in EVPN", draft-ietf-
bess-evpn-prefix-advertisement-11 (work in progress), May
2018.
[I-D.ietf-idr-tunnel-encaps]
Patel, K., Velde, G., Sangli, S., and J. Scudder, "The BGP
Tunnel Encapsulation Attribute", draft-ietf-idr-tunnel-
encaps-17 (work in progress), July 2020.
[RFC0791] Postel, J., "Internet Protocol", STD 5, RFC 791,
DOI 10.17487/RFC0791, September 1981,
<https://www.rfc-editor.org/info/rfc791>.
Sangli & Bonica Expires March 11, 2021 [Page 14]
Internet-DraftBGP based VPN Services over SRm6 enabled IPvSeptember 2020
[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>.
[RFC4303] Kent, S., "IP Encapsulating Security Payload (ESP)",
RFC 4303, DOI 10.17487/RFC4303, December 2005,
<https://www.rfc-editor.org/info/rfc4303>.
[RFC4443] Conta, A., Deering, S., and M. Gupta, Ed., "Internet
Control Message Protocol (ICMPv6) for the Internet
Protocol Version 6 (IPv6) Specification", STD 89,
RFC 4443, DOI 10.17487/RFC4443, March 2006,
<https://www.rfc-editor.org/info/rfc4443>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6
(IPv6) Specification", STD 86, RFC 8200,
DOI 10.17487/RFC8200, July 2017,
<https://www.rfc-editor.org/info/rfc8200>.
15.2. Informative References
[RFC3031] Rosen, E., Viswanathan, A., and R. Callon, "Multiprotocol
Label Switching Architecture", RFC 3031,
DOI 10.17487/RFC3031, January 2001,
<https://www.rfc-editor.org/info/rfc3031>.
[RFC4023] Worster, T., Rekhter, Y., and E. Rosen, Ed.,
"Encapsulating MPLS in IP or Generic Routing Encapsulation
(GRE)", RFC 4023, DOI 10.17487/RFC4023, March 2005,
<https://www.rfc-editor.org/info/rfc4023>.
[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>.
[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>.
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Internet-DraftBGP based VPN Services over SRm6 enabled IPvSeptember 2020
[RFC4659] De Clercq, J., Ooms, D., Carugi, M., and F. Le Faucheur,
"BGP-MPLS IP Virtual Private Network (VPN) Extension for
IPv6 VPN", RFC 4659, DOI 10.17487/RFC4659, September 2006,
<https://www.rfc-editor.org/info/rfc4659>.
[RFC4760] Bates, T., Chandra, R., Katz, D., and Y. Rekhter,
"Multiprotocol Extensions for BGP-4", RFC 4760,
DOI 10.17487/RFC4760, January 2007,
<https://www.rfc-editor.org/info/rfc4760>.
[RFC4761] Kompella, K., Ed. and Y. Rekhter, Ed., "Virtual Private
LAN Service (VPLS) Using BGP for Auto-Discovery and
Signaling", RFC 4761, DOI 10.17487/RFC4761, January 2007,
<https://www.rfc-editor.org/info/rfc4761>.
[RFC4762] Lasserre, M., Ed. and V. Kompella, Ed., "Virtual Private
LAN Service (VPLS) Using Label Distribution Protocol (LDP)
Signaling", RFC 4762, DOI 10.17487/RFC4762, January 2007,
<https://www.rfc-editor.org/info/rfc4762>.
[RFC4817] Townsley, M., Pignataro, C., Wainner, S., Seely, T., and
J. Young, "Encapsulation of MPLS over Layer 2 Tunneling
Protocol Version 3", RFC 4817, DOI 10.17487/RFC4817, March
2007, <https://www.rfc-editor.org/info/rfc4817>.
[RFC5549] Le Faucheur, F. and E. Rosen, "Advertising IPv4 Network
Layer Reachability Information with an IPv6 Next Hop",
RFC 5549, DOI 10.17487/RFC5549, May 2009,
<https://www.rfc-editor.org/info/rfc5549>.
[RFC6624] Kompella, K., Kothari, B., and R. Cherukuri, "Layer 2
Virtual Private Networks Using BGP for Auto-Discovery and
Signaling", RFC 6624, DOI 10.17487/RFC6624, May 2012,
<https://www.rfc-editor.org/info/rfc6624>.
[RFC7432] Sajassi, A., Ed., Aggarwal, R., Bitar, N., Isaac, A.,
Uttaro, J., Drake, J., and W. Henderickx, "BGP MPLS-Based
Ethernet VPN", RFC 7432, DOI 10.17487/RFC7432, February
2015, <https://www.rfc-editor.org/info/rfc7432>.
[RFC7510] Xu, X., Sheth, N., Yong, L., Callon, R., and D. Black,
"Encapsulating MPLS in UDP", RFC 7510,
DOI 10.17487/RFC7510, April 2015,
<https://www.rfc-editor.org/info/rfc7510>.
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Internet-DraftBGP based VPN Services over SRm6 enabled IPvSeptember 2020
[RFC8077] Martini, L., Ed. and G. Heron, Ed., "Pseudowire Setup and
Maintenance Using the Label Distribution Protocol (LDP)",
STD 84, RFC 8077, DOI 10.17487/RFC8077, February 2017,
<https://www.rfc-editor.org/info/rfc8077>.
[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>.
[RFC8317] Sajassi, A., Ed., Salam, S., Drake, J., Uttaro, J.,
Boutros, S., and J. Rabadan, "Ethernet-Tree (E-Tree)
Support in Ethernet VPN (EVPN) and Provider Backbone
Bridging EVPN (PBB-EVPN)", RFC 8317, DOI 10.17487/RFC8317,
January 2018, <https://www.rfc-editor.org/info/rfc8317>.
Authors' Addresses
Srihari Sangli
Juniper Networks Inc.
Exora Business Park
Bangalore, KA 560103
India
Email: ssangli@juniper.net
Ron Bonica
Juniper Networks Inc.
2251 Corporate Park Drive
Herndon, Virginia 20171
USA
Email: rbonica@juniper.net
Sangli & Bonica Expires March 11, 2021 [Page 17]
