BGP Extensions for IDs Allocation

3.1. Node SID NLRI TLV

The Node SID NLRI TLV is used to represent the IDs such as SID associated with a node. Its format is illustrated in the Figure below, which is similar to the corresponding one defined in [RFC7752].¶

 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 (TBDa for Node SID)   |            Length             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Protocol ID   |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                           Identifier                          |
|                           (8 octets)                          |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|  Peer IP (4/16 bytes for IPv4/IPv6 Address)                   ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~                    Local Node Descriptors TLV                 ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~                            Sub-TLVs                           ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Where:¶

Type (TBDa):

It is to be assigned by IANA.¶

Length:

It is the length of the value field in bytes.¶

Peer IP:

4/16 octet value indicates an IPv4/IPv6 peer. When receiving a UPDATE message, a BGP speaker processes it only if the peer IP is the IP address of the BGP speaker or 0.¶

Protocol-ID, Identifier, and Local Node Descriptor:

defined in [RFC7752], can be reused.¶

Sub-TLVs may be some of the followings:¶

SR-Capabilities TLV (1034):

It contains the Segment Routing Global Base (SRGB) range(s) allocated for the node.¶

SR Local Block TLV (1036):

The SR Local Block (SRLB) TLV contains the range(s) of SIDs/labels allocated to the node for local SIDs.¶

SRv6 SID Node TLV (TBD1):

A new TLV, called SRv6 Node SID TLV, contains an SRv6 SID and related information.¶

SRv6 Locator TLV (TBD2):

A new TLV, called SRv6 Locator TLV, contains an SRv6 locator and related information.¶

The format of SRv6 SID Node TLV is illustrated below.¶

 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 (TBD1)          |             Length            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|    Reserved    |     Flags    |     SRv6 Endpoint Function    |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        SRv6 Identifier                        |
|                          (128 bits)                           |
|                                                               |
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                                                               |
~                        Optional sub-TLVs                      ~
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                        SRv6 Node SID TLV

Type:

TBD1 for SRv6 Node SID TLV is to be assigned by IANA.¶

Length:

Variable.¶

Flags:

1 octet. No flags are defined now.¶

SRv6 Endpoint Function:

2 octets. The function associated with SRv6 SID.¶

SRv6 Identifier:

16 octets. IPv6 address representing SRv6 SID.¶

Reserved:

MUST be set to 0 while sending and ignored on receipt.¶

SRv6 node SID inherits the topology and algorithm from its locator.¶

The format of SRv6 locator TLV is illustrated below.¶

 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 (TBD2)          |             Length            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|R|R|R|R|          MT-ID        |   Algorithm   |     Flags     |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                             Metric                            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|  Locator-Size | Locator (variable)...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                                                               |
~                        Optional sub-TLVs                      ~
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                        SRv6 Locator TLV

Type:

TBD2 for SRv6 Locator TLV is to be assigned by IANA.¶

Length:

Variable.¶

MT-ID:

Multitopology Identifier as defined in [RFC5120].¶

Algorithm:

1 octet. Associated algorithm.¶

Flags:

1 octet. As described in [I-D.ietf-lsr-isis-srv6-extensions].¶

Metric:

4 octets. As described in [RFC5305].¶

Locator-Size:

1 octet. Number of bits in the Locator field (1 to 128).¶

Locator:

1 to 16 octets. SRv6 Locator encoded in the minimum number of octets for the given Locator-Size.¶

Reserved:

MUST be set to 0 while sending and ignored on receipt.¶

3.2. Link SID NLRI TLV

The Link SID NLRI TLV is used to represent the IDs such as SID associated with a link. Its format is illustrated in the Figure below, which is similar to the corresponding one defined in [RFC7752].¶

 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 (TBDb for Link SID)   |            Length             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Protocol ID   |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~                    Identifier (8 octets)                      ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|  Peer IP (4/16 bytes for IPv4/IPv6 Address)                   ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~                    Local Node Descriptors TLV                 ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~                    Remote Node Descriptors TLV                ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~                        Link Descriptors TLV                   ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~                            Sub-TLVs                           ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Where:¶

Type (TBDb):

It is to be assigned by IANA.¶

Length:

It is the length of the value field in bytes.¶

Peer IP:

4/16 octet value indicates an IPv4/IPv6 peer.¶

Protocol-ID, Identifier, Local Node Descriptors, Remote Node Descriptors and Link Descriptors:

defined in [RFC7752], can be reused.¶

The Sub-TLVs may be some of the followings:¶

Adj-SID TLV (1099):

It contains the Segment Identifier (SID) allocated for the link/adjacency.¶

LAN Adj-SID TLV (1100):

It contains the Segment Identifier (SID) allocated for the adjacency/link to a non-DR router on a broadcast, NBMA, or hybrid link.¶

SRv6 Adj-SID TLV (TBD3):

A new TLV, called SRv6 Adj-SID TLV, contains an SRv6 Adj-SID and related information.¶

SRv6 LAN Adj-SID TLV (TBD4):

A new TLV, called SRv6 LAN Adj-SID TLV, contains an SRv6 LAN Adj-SID and related information.¶

The format of an SRv6 Adj-SID TLV is illustrated below.¶

 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 (TBD3)          |             Length            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|     Weight    |   Algorithm   |B|S|P|             Flags       |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|           Reserved            |     SRv6 Endpoint Function    |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        SRv6 Identifier                        |
|                          (128 bits)                           |
|                                                               |
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                                                               |
~                        Optional sub-TLVs                      ~
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                         SRv6 Adj-SID TLV

Type:

TBD3 for SRv6 Adj-SID TLV is to be assigned by IANA.¶

Length:

Variable.¶

Weight:

1 octet. The value represents the weight of the SID for the purpose of load balancing.¶

Algorithm:

1 octet. Associated algorithm.¶

Flags:

2 octets. Three flags are defined in [I-D.ietf-lsr-isis-srv6-extensions].¶

SRv6 Endpoint Function:

2 octets. The function associated with SRv6 SID.¶

SRv6 Identifier:

16 octets. IPv6 address representing SRv6 SID.¶

Reserved:

MUST be set to 0 while sending and ignored on receipt.¶

The format of an SRv6 LAN Adj-SID TLV is illustrated below.¶

 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 (TBD4)          |             Length            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|     Weight    |   Algorithm   |B|S|P|             Flags     |O|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|           Reserved            |     SRv6 Endpoint Function    |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|    neighbor Router ID (4 octets) / System ID (6 octets)       ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                        SRv6 Identifier                        |
|                          (128 bits)                           |
|                                                               |
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                                                               |
~                        Optional sub-TLVs                      ~
|                                                               |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                       SRv6 LAN Adj-SID TLV

Type:

TBD4 for SRv6 LAN Adj-SID TLV is to be assigned by IANA.¶

Length:

Variable.¶

Weight:

1 octet. The value represents the weight of the SID for the purpose of load balancing.¶

Algorithm:

1 octet. Associated algorithm.¶

Flags:

2 octets. Three flags B, S and P are defined in [I-D.ietf-lsr-isis-srv6-extensions]. Flag O set to 1 indicating OSPF neighbor Router ID of 4 octets, set to 0 indicating IS-IS neighbor System ID of 6 octets.¶

SRv6 Endpoint Function:

2 octets. The function associated with SRv6 SID.¶

SRv6 Identifier:

16 octets. IPv6 address representing SRv6 SID.¶

Reserved:

MUST be set to 0 while sending and ignored on receipt.¶

3.3. Prefix SID NLRI TLV

The Prefix SID NLRI TLV is used to represent the IDs such as SID associated with a prefix. Its format is illustrated in the Figure below, which is similar to the corresponding one defined in [RFC7752].¶

 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 (TBDc for Prefix SID)  |            Length             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Protocol ID   |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~                       Identifier (8 octets)                   ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|  Peer IP (4/16 bytes for IPv4/IPv6 Address)                   ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~                    Local Node Descriptors TLV                 ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~                        Prefix Descriptors TLV                 ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~                            Sub-TLVs                           ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Where:¶

Type (TBDc):

It is to be assigned by IANA.¶

Length:

It is the length of the value field in bytes.¶

Peer IP:

4/16 octet value indicates an IPv4/IPv6 peer.¶

Protocol-ID, Identifier, Local Node Descriptors and Prefix Descriptors:

defined in [RFC7752], can be reused.¶

Sub-TLVs may be some of the followings:¶

Prefix-SID TLV (1158):

It contains the Segment Identifier (SID) allocated for the prefix.¶

Prefix Range TLV (1159):

It contains a range of prefixes and the Segment Identifier (SID)s allocated for the prefixes.¶

3.4. Capability Negotiation

It is necessary to negotiate the capability to support BGP Extensions for sending and receiving Segment Identifiers (SIDs). The BGP SID Capability is a new BGP capability [RFC5492]. The Capability Code for this capability is to be specified by the IANA. The Capability Length field of this capability is variable. The Capability Value field consists of one or more of the following tuples:¶

+--------------------------------------------------+
|  Address Family Identifier (2 octets)            |
+--------------------------------------------------+
|  Subsequent Address Family Identifier (1 octet)  |
+--------------------------------------------------+
|  Send/Receive (1 octet)                          |
+--------------------------------------------------+

               BGP SID Capability

The meaning and use of the fields are as follows:¶

Address Family Identifier (AFI): This field is the same as the one used in [RFC4760].¶

Subsequent Address Family Identifier (SAFI): This field is the same as the one used in [RFC4760].¶

Send/Receive: This field indicates whether the sender is (a) willing to receive SID from its peer (value 1), (b) would like to send SID to its peer (value 2), or (c) both (value 3) for the <AFI, SAFI>.¶

7.1. Normative References

[I-D.ietf-idr-flowspec-path-redirect]

Velde, G. V. D., Patel, K., and Z. Li, "Flowspec Indirection-id Redirect", Work in Progress, Internet-Draft, draft-ietf-idr-flowspec-path-redirect-11, 26 May 2020, <https://www.ietf.org/archive/id/draft-ietf-idr-flowspec-path-redirect-11.txt>.

[I-D.ietf-isis-segment-routing-extensions]

Previdi, S., Ginsberg, L., Filsfils, C., Bashandy, A., Gredler, H., and B. Decraene, "IS-IS Extensions for Segment Routing", Work in Progress, Internet-Draft, draft-ietf-isis-segment-routing-extensions-25, 19 May 2019, <https://www.ietf.org/archive/id/draft-ietf-isis-segment-routing-extensions-25.txt>.

[I-D.ietf-lsr-isis-srv6-extensions]

Psenak, P., Filsfils, C., Bashandy, A., Decraene, B., and Z. Hu, "IS-IS Extensions to Support Segment Routing over IPv6 Dataplane", Work in Progress, Internet-Draft, draft-ietf-lsr-isis-srv6-extensions-18, 20 October 2021, <https://www.ietf.org/archive/id/draft-ietf-lsr-isis-srv6-extensions-18.txt>.

[I-D.ietf-rtgwg-bgp-routing-large-dc]

Lapukhov, P., Premji, A., and J. Mitchell, "Use of BGP for Routing in Large-Scale Data Centers", Work in Progress, Internet-Draft, draft-ietf-rtgwg-bgp-routing-large-dc-11, 4 June 2016, <https://www.ietf.org/archive/id/draft-ietf-rtgwg-bgp-routing-large-dc-11.txt>.

[I-D.ietf-spring-segment-routing]

Filsfils, C., Previdi, S., Ginsberg, L., Decraene, B., Litkowski, S., and R. Shakir, "Segment Routing Architecture", Work in Progress, Internet-Draft, draft-ietf-spring-segment-routing-15, 25 January 2018, <https://www.ietf.org/archive/id/draft-ietf-spring-segment-routing-15.txt>.

[I-D.ietf-spring-segment-routing-ldp-interop]

Bashandy, A., Filsfils, C., Previdi, S., Decraene, B., and S. Litkowski, "Segment Routing MPLS Interworking with LDP", Work in Progress, Internet-Draft, draft-ietf-spring-segment-routing-ldp-interop-15, 2 September 2018, <https://www.ietf.org/archive/id/draft-ietf-spring-segment-routing-ldp-interop-15.txt>.

[I-D.li-ospf-ospfv3-srv6-extensions]

Li, Z., Hu, Z., Cheng, D., Talaulikar, K., and P. Psenak, "OSPFv3 Extensions for SRv6", Work in Progress, Internet-Draft, draft-li-ospf-ospfv3-srv6-extensions-07, 4 November 2019, <https://www.ietf.org/archive/id/draft-li-ospf-ospfv3-srv6-extensions-07.txt>.

[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>.

[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>.

[RFC5120]

Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi Topology (MT) Routing in Intermediate System to Intermediate Systems (IS-ISs)", RFC 5120, DOI 10.17487/RFC5120, February 2008, <https://www.rfc-editor.org/info/rfc5120>.

[RFC5305]

Li, T. and H. Smit, "IS-IS Extensions for Traffic Engineering", RFC 5305, DOI 10.17487/RFC5305, October 2008, <https://www.rfc-editor.org/info/rfc5305>.

[RFC5492]

Scudder, J. and R. Chandra, "Capabilities Advertisement with BGP-4", RFC 5492, DOI 10.17487/RFC5492, February 2009, <https://www.rfc-editor.org/info/rfc5492>.

[RFC5575]

Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J., and D. McPherson, "Dissemination of Flow Specification Rules", RFC 5575, DOI 10.17487/RFC5575, August 2009, <https://www.rfc-editor.org/info/rfc5575>.

[RFC7752]

Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and S. Ray, "North-Bound Distribution of Link-State and Traffic Engineering (TE) Information Using BGP", RFC 7752, DOI 10.17487/RFC7752, March 2016, <https://www.rfc-editor.org/info/rfc7752>.

[RFC8126]

Cotton, M., Leiba, B., and T. Narten, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 8126, DOI 10.17487/RFC8126, June 2017, <https://www.rfc-editor.org/info/rfc8126>.

7.2. Informative References

[I-D.gredler-idr-bgp-ls-segment-routing-extension]

Gredler, H., Ray, S., Previdi, S., Filsfils, C., Chen, M., and J. Tantsura, "BGP Link-State extensions for Segment Routing", Work in Progress, Internet-Draft, draft-gredler-idr-bgp-ls-segment-routing-extension-02, 16 October 2014, <https://www.ietf.org/archive/id/draft-gredler-idr-bgp-ls-segment-routing-extension-02.txt>.

[I-D.ietf-idr-bgpls-segment-routing-epe]

Previdi, S., Talaulikar, K., Filsfils, C., Patel, K., Ray, S., and J. Dong, "Border Gateway Protocol - Link State (BGP-LS) Extensions for Segment Routing BGP Egress Peer Engineering", Work in Progress, Internet-Draft, draft-ietf-idr-bgpls-segment-routing-epe-19, 16 May 2019, <https://www.ietf.org/archive/id/draft-ietf-idr-bgpls-segment-routing-epe-19.txt>.

[I-D.ietf-teas-enhanced-vpn]

Dong, J., Bryant, S., Li, Z., Miyasaka, T., and Y. Lee, "A Framework for Enhanced Virtual Private Network (VPN+) Services", Work in Progress, Internet-Draft, draft-ietf-teas-enhanced-vpn-10, 6 March 2022, <https://www.ietf.org/archive/id/draft-ietf-teas-enhanced-vpn-10.txt>.