< draft-wang-lsr-stub-link-attributes-00.txt   draft-wang-lsr-stub-link-attributes-01.txt >
LSR Working Group A. Wang LSR Working Group A. Wang
Internet-Draft China Telecom Internet-Draft China Telecom
Intended status: Standards Track Z. Hu Intended status: Standards Track Z. Hu
Expires: 1 February 2022 Huawei Technologies Expires: March 26, 2022 Huawei Technologies
G. Mishra G. Mishra
Verizon Inc. Verizon Inc.
A. Lindem
Cisco Systems
J. Sun J. Sun
ZTE Corporation ZTE Corporation
31 July 2021 September 22, 2021
Advertisement of Stub Link Attributes Advertisement of Stub Link Attributes
draft-wang-lsr-stub-link-attributes-00 draft-wang-lsr-stub-link-attributes-01
Abstract Abstract
This document describes the mechanism that can be used to This document describes the mechanism that can be used to
differentiate the stub links from the normal interfaces within ISIS differentiate the stub links from the normal interfaces within ISIS
or OSPF domain. or OSPF domain.
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
skipping to change at page 1, line 37 skipping to change at page 1, line 39
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Conventions used in this document . . . . . . . . . . . . . . 3 2. Conventions used in this document . . . . . . . . . . . . . . 3
3. Consideration for flagging passive interface . . . . . . . . 3 3. Consideration for Identifying Stub Link . . . . . . . . . . . 3
4. Passive Interface Attribute . . . . . . . . . . . . . . . . . 4 4. Protocol Extension for Stub Link Attributes . . . . . . . . . 3
4.1. OSPFv2 Extended Stub-Link TLV . . . . . . . . . . . . . . 4 4.1. OSPF Stub-Link TLV . . . . . . . . . . . . . . . . . . . 4
4.2. OSPFv3 Router-Stub-Link TLV . . . . . . . . . . . . . . . 5 4.2. ISIS Stub-link Sub-TLV . . . . . . . . . . . . . . . . . 5
4.3. ISIS Stub-link TLV . . . . . . . . . . . . . . . . . . . 6 5. Security Considerations . . . . . . . . . . . . . . . . . . . 6
4.4. Stub-Link Prefix Sub-TLV . . . . . . . . . . . . . . . . 7 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6
5. Security Considerations . . . . . . . . . . . . . . . . . . . 8 7. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 6
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 7
7. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 9 8.1. Normative References . . . . . . . . . . . . . . . . . . 7
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 9 8.2. Informative References . . . . . . . . . . . . . . . . . 7
8.1. Normative References . . . . . . . . . . . . . . . . . . 9 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8
8.2. Informative References . . . . . . . . . . . . . . . . . 10
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11
1. Introduction 1. Introduction
Stub links are used commonly within an operators enterprise or Stub links are used commonly within an operators enterprise or
service provider networks. One of the most common use cases for stub service provider networks. One of the most common use cases for stub
links is in a data center Layer 2 and Layer 3 Top of Rack(TOR) switch links is in a data center Layer 2 and Layer 3 Top of Rack(TOR) switch
where the inter connected links between the TOR switches and uplinks where the inter connected links between the TOR switches and uplinks
to the core switch are only a few links and a majority of the links to the core switch are only a few links and a majority of the links
are Layer 3 VLAN switched virtual interface trunked between the TOR are Layer 3 VLAN switched virtual interface trunked between the TOR
switches serving Layer 2 broadcast domains. In this scenario all the switches serving Layer 2 broadcast domains. In this scenario all the
VLANs are made as stub links as it is recommended to limit the number VLANs are made as stub links as it is recommended to limit the number
of network LSAs between routers and switches to avoid unnecessary of network LSAs between routers and switches to avoid unnecessary
hello processing overhead. hello processing overhead.
Another common use case is an inter-as routing scenario where the Another common use case is an inter-AS routing scenario where the
same routing protocol but different IGP instance is running between same routing protocol but different IGP instance is running between
the adjacent BGP domains. Using stub link on the inter-as the adjacent BGP domains. Using stub link on the inter-AS
connections can ensure that prefixes contained within a domain are connections can ensure that prefixes contained within a domain are
only reachable within the domain itself and not allow the link state only reachable within the domain itself and not allow the link state
database to be merged between domain which could result in database to be merged between domain which could result in
undesirable consequences. undesirable consequences.
For operator which runs different IGP domains that interconnect with For operator which runs different IGP domains that interconnect with
each other via the stub links, there is desire to obtain the inter-as each other via the stub links, there is desire to obtain the inter-AS
topology information as described in topology information as described in
[I-D.ietf-idr-bgpls-inter-as-topology-ext]. If the router that runs [I-D.ietf-idr-bgpls-inter-as-topology-ext]. If the router that runs
BGP-LS within one IGP domain can distinguish stub links from other BGP-LS within one IGP domain can distinguish stub links from other
normal interfaces, it is then easy for the router to report these normal interfaces, it is then easy for the router to report these
stub links using BGP-LS to a centralized PCE controller. stub links using BGP-LS to a centralized PCE controller.
Draft [I-D.dunbar-lsr-5g-edge-compute-ospf-ext] describes the case Draft [I-D.dunbar-lsr-5g-edge-compute] describes the case that edge
that edge compute server attach the network and needs to flood some compute server attach the network and needs to flood some performance
performance index information to the network to facilitate the index information to the network to facilitate the network select the
network select the optimized application resource. The edge compute optimized application resource. The edge compute server will also
server will also not run IGP protocol. not run IGP protocol.
And, stub links are normally the boundary of one IGP domain, knowing And, stub links are normally the boundary of one IGP domain, knowing
them can facilitate the operators to apply various policies on such them can facilitate the operators to apply various policies on such
interfaces, for example, to secure their networks, or filtering the interfaces, for example, to secure their networks, or filtering the
incoming traffic with scrutiny. incoming traffic with scrutiny.
But OSPF and ISIS have no position to flag such stub links and their But OSPF and ISIS have no position to identify such stub links and
associated attributes now. their associated attributes now.
This document defines the protocol extension for OSPF and ISIS to This document defines the protocol extension for OSPFv2/v3 and ISIS
indicate the stub links and their associated attributes. to indicate the stub links and their associated attributes.
2. Conventions used in this document 2. Conventions used in this document
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 [RFC2119] . document are to be interpreted as described in [RFC2119] .
3. Consideration for flagging passive interface 3. Consideration for Identifying Stub Link
ISIS[RFC5029] defines the Link-Attributes Sub-TLV to carry the link
attribute information, but this Sub-TLV can only be carried within
the TLV 22, which is used to described the attached neighbor. For
stub link, there is no ISIS neighbor, then it is not appropriate to
use this Sub-TLV to indicate the attribute of such link.
OSPFv2[RFC2328] defines link type field within Router LSA, the type 3 OSPF[RFC5392] defines the Inter-AS-TE-v2 LSA and Inter-AS-TE-v3 LSA
for connections to a stub network can be used to identified the stub to carry the TE information about inter-AS links. These LSAs can be
link. But in OSPFv3[RFC5340], type 3 within the Router-LSA has been used to transfer the information about the stub link which is located
reserved. The information that associated with stub network has been at the boundary of one AS. This document defines the Stub-Link TLV
put in the Intra-Area-Prefix-LSAs. within these LSAs to identify the stub link and transfer the
associated attributes then.
It is necessary to define one general solution for ISIS and OSPF to ISIS[RFC5316] defines the Inter-AS Reachability TLV to carry the TE
flag the stub link and transfer the associated attributes then. information about inter-AS links. This TLV can be used to transfer
the information about the stub link which is located at the boundary
of one AS. This document defines the Stub-Link sub-TLV within this
TLV to identify the stub link and transfer the associated attributes.
4. Passive Interface Attribute 4. Protocol Extension for Stub Link Attributes
The following sections define the protocol extension to indicate the The following sections define the protocol extension to indicate the
stub link and its associated attributes in OSPFv2/v3 and ISIS. stub link and its associated attributes in OSPFv2/v3 and ISIS.
4.1. OSPFv2 Extended Stub-Link TLV 4.1. OSPF Stub-Link TLV
[RFC7684] defines the OSPFv2 Extended Link Opaque LSA to contain the This document defines the OSPF Stub-Link TLV to describe stub link of
additional link attribute TLV. Currently, only OSPFv2 Extended Link a single router. This Stub-Link TLV is only applicable to the Inter-
TLV is defined to contain the link related sub-TLV. Because stub AS-TE-v2 LSA and Inter-AS-TE-v3 LSA. Inclusion in other LSA MUST be
link is not the normal link that participate in the OSPFv2 process, ignored.
we select to define one new top TLV within the OSPFv2 Extended Link
Opaque LSA to contain the stub link related attribute information.
The OSPFv2 Extended Stub-Link TLV has the following format: The OSPF Stub-Link TLV which is under the IANA codepoint "Top Level
Types in TE LSAs" 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(Stub-Link) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Type | Reserved | Metric | | Type(Stub-Link) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link ID | | Link Type | Prefix Length | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Data | | Link Prefix(variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-TLVs (variable) | | Sub-TLVs (variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: OSPFv2 Extended Stub-Link TLV Figure 1: OSPF Stub-Link TLV
Type: The TLV type. The value is 2(TBD) for this stub-link type Type: The TLV type. The value is 7(TBD) for OSPF Stub-Link
Length: Variable, dependent on sub-TLVs Length: Variable, dependent on sub-TLVs
Link Type: Define the type of the stub-link. This document defines Link Type: Define the type of the stub-link. This document defines
the followings type: the followings type:
* 0: Reserved o 0: Reserved
* 1: AS boundary link o 1: AS boundary link
* 2: Loopback link o 2: Loopback link
* 3: Vlan interface link o 3: Vlan interface link
* 4-255: For future extension o 4-255: For future extension
Metric: Link metric used for inter-AS traffic engineering.
Link ID: Link ID is defined in Section A.4.2 of [RFC2328] Prefix Length: The length of the interface address, in octet.
Link Data: Link Data is defined in Section A.4.2 of [RFC2328] Link Prefix: The prefix of the stub-link. It's length is determined
by the field "Prefix Length".
Sub-TLVs: Existing sub-TLV that defined within "OSPFv2 Extended Link Sub-TLVs: Existing sub-TLV that defined within "Open Shortest Path
TLV Sub-TLV" can be included if necessary, the definition of new sub- First (OSPF) Traffic Engineering TLVs" for TE Link TLV(Value 2) can
TLV can refer to Section 4.4 be included if necessary.
If this TLV is advertised multiple times in the same OSPFv2 Extended If this TLV is advertised multiple times in the same Inter-AS-TE-v2/
Link Opaque LSA, only the first instance of the TLV is used by v3 LSA, only the first instance of the TLV is used by receiving
receiving OSPFv2 routers. This situation SHOULD be logged as an OSPFv2/v3 routers. This situation SHOULD be logged as an error.
error.
If this TLV is advertised multiple times for the same link in If this TLV is advertised multiple times for the same link in
different OSPFv2 Extended Link Opaque LSAs originated by the same different Inter-AS-TE-v2/v3 LSA originated by the same OSPFrouter,
OSPFv2 router, the OSPFv2 Extended Stub-Link TLV in the OSPFv2 the OSPFStub-Link TLV in these LSAs with the smallest Opaque ID is
Extended Link Opaque LSA with the smallest Opaque ID is used by used by receiving OSPFrouters. This situation may be logged as a
receiving OSPFv2 routers. This situation may be logged as a warning. warning.
It is RECOMMENDED that OSPFv2 routers advertising OSPFv2 Extended It is RECOMMENDED that OSPF routers advertising OSPF Stub-Link TLVs
Stub-Link TLVs in different OSPFv2 Extended Link Opaque LSAs re- in different OSPF Inter-AS-TE v2/v3 LSAs re-originate these LSAs in
originate these LSAs in ascending order of Opaque ID to minimize the ascending order of Opaque ID to minimize the disruption.
disruption.
This document creates a registry for Stub-Link attribute in This document creates a registry for Stub-Link attributes in
Section 6. Section 6.
4.2. OSPFv3 Router-Stub-Link TLV 4.2. ISIS Stub-link Sub-TLV
[RFC8362] extend the LSA format by encoding the existing OSPFv3 LSA
[RFC5340] in TLV tuples and allowing advertisement of additional
information with additional TLV.
This document defines the Router-Stub-Link TLV to describes stub link
of a single router. The Router-Stub-Link TLV is only applicable to
the E-Router-LSA. Inclusion in other Extended LSA MUST be ignored.
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(Router-Stub-Link) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Type | Reserved | Metric |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Interface ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-TLVs(Variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: OSPFv3 Router-Stub-Link TLV
Type: OSPFv3 Extended-LSA TLV Type. Value is 10(TBD) for Router-
Stub-Link TLV.
Length: Variable, dependent on sub-TLVs
Link Type: Define the type of the stub-link. This document defines
the followings type:
* 0: Reserved
* 1: AS boundary link
* 2: Loopback link
* 3: Vlan interface link
* 4-255: For future extension
Metric: Link metric used for inter-AS traffic engineering.
Interface ID: 32-bit number uniquely identifying this interface among
the collection of this router's interfaces. For example, in some
implementations it may be possible to use the MIB-II IfIndex
[RFC2863].
Sub-TLVs: Existing sub-TLV that defined within "OSPFv3 Extended-LSA
Sub-TLV" can be included if necessary. The definition of new sub-TLV
can refer to Section 4.4.
4.3. ISIS Stub-link TLV This document defines the ISIS Stub-Link sub-TLV to describes stub
link of a single router. This Stub-Link sub-TLV is only applicable
to the Inter-AS Reachability TLV. Inclusion in other TLV MUST be
ignored.
This document defines one new top TLV to contain the stub link The ISIS Stub-Link sub-TLV which is under the IANA codepoint "Sub-
attributes, which is shown in Figure 4: TLVs for TLVs 22, 23, 25, 141, 222, and 223" 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(Stub-Link) | Length | | Type(Stub-Link) | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Link Type | Reserved | Metric | | Link Type | Prefix Length | Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Interface ID | | Link Prefix(variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-TLVs(Variable) | | Sub-TLVs(Variable) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: ISIS Stub-Link TLV Figure 2: ISIS Stub-Link Sub-TLV
Type: ISIS TLV Codepoint. Value is 28(TBD) for stub-link TLV. Type: ISIS sub-TLV codepoint. Value is 45(TBD) for stub-link TLV.
Length: Variable, dependent on sub-TLVs Length: Variable, dependent on sub-TLVs
Link Type: Define the type of the stub-link. This document defines Link Type: Define the type of the stub-link. This document defines
the followings type: the followings type:
* 0: Reserved o 0: Reserved
* 1: AS boundary link
* 2: Loopback link
* 3: Vlan interface link
* 4-255: For future extension
Metric: Link metric used for inter-AS traffic engineering.
Interface ID: 32-bit number uniquely identifying this interface among
the collection of this router's interfaces. For example, in some
implementations it may be possible to use the MIB-II IfIndex
[RFC2863].
Sub-TLVs: Existing sub-TLV that defined within "Sub-TLVs for TLVs 22,
23, 25, 141, 222, and 223" can be included if necessary. The
definition of new sub-TLV can refer to Section 4.4.
4.4. Stub-Link Prefix Sub-TLV
This document defines one new sub-TLV that can be contained within o 1: AS boundary link
the OSPFv2 Extended Stub-Link TLV , OSPFv3 Router-Stub-Link TLV or
ISIS Stub-Link TLV, to describe the prefix information associated
with the stub link.
The format of the sub-TLV is the followings: o 2: Loopback link
0 1 2 3 o 3: Vlan interface link
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 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv4 Prefix or IPv6 Prefix Subobject |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: Stub-Link Prefix Sub-TLV
Type: The TLV type. The value is 01(TBD) for this Stub-Link Prefix o 4-255: For future extension
type
Length: Variable, dependent on associated subobjects Prefix Length: The length of the interface address, in octet.
Subobject: IPv4 prefix subobject or IPv6 prefix subobject, as that Link Prefix: The prefix of the stub-link. It's length is determined
defined in [RFC3209] by the field "Prefix Length".
If the stub link has multiple address, then multiple subobjects will Sub-TLVs: Existing sub-TLVs that defined within "Sub-TLVs for TLVs
be included within this sub-TLV. 22, 23, 25, 141, 222, and 223" can be included if necessary.
5. Security Considerations 5. Security Considerations
Security concerns for ISIS are addressed in [RFC5304] and[RFC5310] Security concerns for ISIS are addressed in [RFC5304] and[RFC5310]
Security concern for OSPFv3 is addressed in [RFC4552] Security concern for OSPFv3 is addressed in [RFC4552]
Advertisement of the additional information defined in this document Advertisement of the additional information defined in this document
introduces no new security concerns. introduces no new security concerns.
6. IANA Considerations 6. IANA Considerations
IANA is requested to the allocation in following registries: IANA is requested to the allocation in following registries:
+=========================+===========+======================+ +===========================+======+===========================+
| Registry | Type | Meaning | | Registry | Type | Meaning |
+=========================+===========+======================+ +===========================+======+===========================+
|OSPFv2 Extended Link | 2 |Stub-Link TLV | |Top Level Types in TE LSAs | 7 |OSPF Stub-Link TLV |
|Opaque LSA TLV | | | +---------------------------+------+---------------------------+
+-------------------------+-----------+----------------------+ |Sub-TLVs for TLVs 22, 23, | | |
|OSPFv3 Extended-LSA TLV | 10 |Router-Stub-Link TLV | | 25, 141, 222, and 223 | 45 |IS-IS Stub-Link sub-TLV |
+-------------------------+-----------+----------------------+ +---------------------------+------+---------------------------+
|IS-IS TLV Codepoint | 28 |Stub-Link TLV | Figure 3: IANA Allocation for newly defined TLVs
+-------------------------+-----------+----------------------+
Figure 5: Newly defined TLV in existing IETF registry
IANA is requested to allocate one new registry that can be referred
by OSPFv2, OSPFv3 and ISIS respectively.
+=========================+==================================+
| New Registry | Meaning |
+=========================+==================================+
|Stub-Link Attribute | Attributes for stub-link |
+-------------------------+----------------------------------+
Figure 6: Newly defined Registry for stub-link attributes
One new sub-TLV is defined in this document under this registry
codepoint:
+=========================+===========+===============================+
| Registry | Type | Meaning |
+=========================+===========+===============================+
|Stub-Link Attribute | 0 | Reserved
+=========================+===========+===============================+
| | 1 |Stub-Link Prefix sub-TLV |
+-------------------------+-----------+-------------------------------+
| | 2-65535 |Reserved |
+-------------------------+-----------+-------------------------------+
Figure 7: Stub-Link Prefix Sub-TLV
7. Acknowledgement 7. Acknowledgement
Thanks Shunwan Zhang, Tony Li, Les Ginsberg, Acee Lindem, Dhruv Thanks Shunwan Zhang, Tony Li, Les Ginsberg, Acee Lindem, Dhruv
Dhody, Jeff Tantsura and Robert Raszuk for their suggestions and Dhody, Jeff Tantsura and Robert Raszuk for their suggestions and
comments on this idea. comments on this idea.
8. References 8. References
8.1. Normative References 8.1. 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>.
[RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328,
DOI 10.17487/RFC2328, April 1998,
<https://www.rfc-editor.org/info/rfc2328>.
[RFC2863] McCloghrie, K. and F. Kastenholz, "The Interfaces Group
MIB", RFC 2863, DOI 10.17487/RFC2863, June 2000,
<https://www.rfc-editor.org/info/rfc2863>.
[RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001,
<https://www.rfc-editor.org/info/rfc3209>.
[RFC4552] Gupta, M. and N. Melam, "Authentication/Confidentiality [RFC4552] Gupta, M. and N. Melam, "Authentication/Confidentiality
for OSPFv3", RFC 4552, DOI 10.17487/RFC4552, June 2006, for OSPFv3", RFC 4552, DOI 10.17487/RFC4552, June 2006,
<https://www.rfc-editor.org/info/rfc4552>. <https://www.rfc-editor.org/info/rfc4552>.
[RFC5029] Vasseur, JP. and S. Previdi, "Definition of an IS-IS Link
Attribute Sub-TLV", RFC 5029, DOI 10.17487/RFC5029,
September 2007, <https://www.rfc-editor.org/info/rfc5029>.
[RFC5304] Li, T. and R. Atkinson, "IS-IS Cryptographic [RFC5304] Li, T. and R. Atkinson, "IS-IS Cryptographic
Authentication", RFC 5304, DOI 10.17487/RFC5304, October Authentication", RFC 5304, DOI 10.17487/RFC5304, October
2008, <https://www.rfc-editor.org/info/rfc5304>. 2008, <https://www.rfc-editor.org/info/rfc5304>.
[RFC5310] Bhatia, M., Manral, V., Li, T., Atkinson, R., White, R., [RFC5310] Bhatia, M., Manral, V., Li, T., Atkinson, R., White, R.,
and M. Fanto, "IS-IS Generic Cryptographic and M. Fanto, "IS-IS Generic Cryptographic
Authentication", RFC 5310, DOI 10.17487/RFC5310, February Authentication", RFC 5310, DOI 10.17487/RFC5310, February
2009, <https://www.rfc-editor.org/info/rfc5310>. 2009, <https://www.rfc-editor.org/info/rfc5310>.
[RFC5340] Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF [RFC5316] Chen, M., Zhang, R., and X. Duan, "ISIS Extensions in
for IPv6", RFC 5340, DOI 10.17487/RFC5340, July 2008, Support of Inter-Autonomous System (AS) MPLS and GMPLS
<https://www.rfc-editor.org/info/rfc5340>. Traffic Engineering", RFC 5316, DOI 10.17487/RFC5316,
December 2008, <https://www.rfc-editor.org/info/rfc5316>.
[RFC7684] Psenak, P., Gredler, H., Shakir, R., Henderickx, W.,
Tantsura, J., and A. Lindem, "OSPFv2 Prefix/Link Attribute
Advertisement", RFC 7684, DOI 10.17487/RFC7684, November
2015, <https://www.rfc-editor.org/info/rfc7684>.
[RFC7794] Ginsberg, L., Ed., Decraene, B., Previdi, S., Xu, X., and
U. Chunduri, "IS-IS Prefix Attributes for Extended IPv4
and IPv6 Reachability", RFC 7794, DOI 10.17487/RFC7794,
March 2016, <https://www.rfc-editor.org/info/rfc7794>.
[RFC8362] Lindem, A., Roy, A., Goethals, D., Reddy Vallem, V., and [RFC5392] Chen, M., Zhang, R., and X. Duan, "OSPF Extensions in
F. Baker, "OSPFv3 Link State Advertisement (LSA) Support of Inter-Autonomous System (AS) MPLS and GMPLS
Extensibility", RFC 8362, DOI 10.17487/RFC8362, April Traffic Engineering", RFC 5392, DOI 10.17487/RFC5392,
2018, <https://www.rfc-editor.org/info/rfc8362>. January 2009, <https://www.rfc-editor.org/info/rfc5392>.
8.2. Informative References 8.2. Informative References
[I-D.dunbar-lsr-5g-edge-compute-ospf-ext] [I-D.dunbar-lsr-5g-edge-compute]
Dunbar, L., Chen, H., and A. Wang, "OSPF extension for 5G Dunbar, L., Chen, H., and C. Telecom, "IS-IS & OSPF
Edge Computing Service", Work in Progress, Internet-Draft, extension for 5G Edge Computing Service", draft-dunbar-
draft-dunbar-lsr-5g-edge-compute-ospf-ext-04, 10 March lsr-5g-edge-compute-00 (work in progress), July 2021.
2021, <https://www.ietf.org/archive/id/draft-dunbar-lsr-
5g-edge-compute-ospf-ext-04.txt>.
[I-D.ietf-idr-bgpls-inter-as-topology-ext] [I-D.ietf-idr-bgpls-inter-as-topology-ext]
Wang, A., Chen, H., Talaulikar, K., and S. Zhuang, "BGP-LS Wang, A., Chen, H., Talaulikar, K., and S. Zhuang, "BGP-LS
Extension for Inter-AS Topology Retrieval", Work in Extension for Inter-AS Topology Retrieval", draft-ietf-
Progress, Internet-Draft, draft-ietf-idr-bgpls-inter-as- idr-bgpls-inter-as-topology-ext-09 (work in progress),
topology-ext-09, 28 September 2020, September 2020.
<https://www.ietf.org/archive/id/draft-ietf-idr-bgpls-
inter-as-topology-ext-09.txt>.
Authors' Addresses Authors' Addresses
Aijun Wang Aijun Wang
China Telecom China Telecom
Beiqijia Town, Changping District Beiqijia Town, Changping District
Beijing Beijing 102209
102209
China China
Email: wangaj3@chinatelecom.cn Email: wangaj3@chinatelecom.cn
Zhibo Hu Zhibo Hu
Huawei Technologies Huawei Technologies
Huawei Bld., No.156 Beiqing Rd. Huawei Bld., No.156 Beiqing Rd.
Beijing Beijing 100095
100095
China China
Email: huzhibo@huawei.com Email: huzhibo@huawei.com
Gyan S. Mishra Gyan S. Mishra
Verizon Inc. Verizon Inc.
13101 Columbia Pike 13101 Columbia Pike
Silver Spring, MD 20904 Silver Spring MD 20904
United States of America United States of America
Email: gyan.s.mishra@verizon.com Email: gyan.s.mishra@verizon.com
Acee Lindem
Cisco Systems
No. 301 Midenhall Way
Cary NC 27513
United States of America
Email: acee@cisco.com
Jinsong Sun Jinsong Sun
ZTE Corporation ZTE Corporation
No. 68, Ziijnhua Road No. 68, Ziijnhua Road
Nan Jing Nan Jing 210012
210012
China China
Email: sun.jinsong@zte.com.cn Email: sun.jinsong@zte.com.cn
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