IS-IS TLV Codepoints

Created
2003-05-06
Last Updated
2020-10-23
Note
For IS-IS registries and value ranges maintained via the "Expert Review" [RFC8126] 
registration procedure, guidance for IESG-designated experts can be found in 
[RFC7370].
Available Formats

XML
HTML
Plain text

Registries included below

TLV Codepoints Registry

Registration Procedure(s)
Expert Review
Expert(s)
Chris Hopps, Hannes Gredler, Les Ginsberg
Reference
[RFC3563][RFC6233][RFC7356][RFC8918]
Note
IETF SHALL keep JTC1/SC6 informed of TLV codepoint values allocated,
and JTC1/SC6 SHALL refer allocation requests arising within JTC1
constituencies to the IANA registry process.
Note
Codepoints greater than 255 can only be used in PDUs designated to 
support extended TLVs.
Available Formats

CSV
Value Name IIH LSP SNP Purge Status/Reference
0 Reserved
1 Area Addresses y y n n [ISO 10589, "Intermediate System to Intermediate System Intra- Domain Routeing Exchange Protocol for use in Conjunction with the Protocol for Providing the Connectionless-mode Network Service (ISO 8473)", International Standard 10589: 2002, Second Edition, 2002.]
2 IIS Neighbors n y n n [ISO 10589, "Intermediate System to Intermediate System Intra- Domain Routeing Exchange Protocol for use in Conjunction with the Protocol for Providing the Connectionless-mode Network Service (ISO 8473)", International Standard 10589: 2002, Second Edition, 2002.]
3 ES Neighbors n y n n [ISO 10589, "Intermediate System to Intermediate System Intra- Domain Routeing Exchange Protocol for use in Conjunction with the Protocol for Providing the Connectionless-mode Network Service (ISO 8473)", International Standard 10589: 2002, Second Edition, 2002.]
4 Part. DIS n y n n [ISO 10589, "Intermediate System to Intermediate System Intra- Domain Routeing Exchange Protocol for use in Conjunction with the Protocol for Providing the Connectionless-mode Network Service (ISO 8473)", International Standard 10589: 2002, Second Edition, 2002.]
5 Prefix Neighbors n y n n [ISO 10589, "Intermediate System to Intermediate System Intra- Domain Routeing Exchange Protocol for use in Conjunction with the Protocol for Providing the Connectionless-mode Network Service (ISO 8473)", International Standard 10589: 2002, Second Edition, 2002.]
6 IIS Neighbors y n n n [ISO 10589, "Intermediate System to Intermediate System Intra- Domain Routeing Exchange Protocol for use in Conjunction with the Protocol for Providing the Connectionless-mode Network Service (ISO 8473)", International Standard 10589: 2002, Second Edition, 2002.]
7 Instance Identifier y y y y [RFC8202]
8 Padding y n n n [ISO 10589, "Intermediate System to Intermediate System Intra- Domain Routeing Exchange Protocol for use in Conjunction with the Protocol for Providing the Connectionless-mode Network Service (ISO 8473)", International Standard 10589: 2002, Second Edition, 2002.]
9 LSP Entries n n y n [ISO 10589, "Intermediate System to Intermediate System Intra- Domain Routeing Exchange Protocol for use in Conjunction with the Protocol for Providing the Connectionless-mode Network Service (ISO 8473)", International Standard 10589: 2002, Second Edition, 2002.]
10 Authentication y y y y [ISO 10589, "Intermediate System to Intermediate System Intra- Domain Routeing Exchange Protocol for use in Conjunction with the Protocol for Providing the Connectionless-mode Network Service (ISO 8473)", International Standard 10589: 2002, Second Edition, 2002.][RFC6233]
11 ESN TLV y n y n [RFC7602]
12 Opt. Checksum y n y n [RFC3358]
13 Purge Originator Identification n n n y [RFC8918]
14 LSPBufferSize n y n n [ISO 10589, "Intermediate System to Intermediate System Intra- Domain Routeing Exchange Protocol for use in Conjunction with the Protocol for Providing the Connectionless-mode Network Service (ISO 8473)", International Standard 10589: 2002, Second Edition, 2002.]
15 Router-Fingerprint y y n y [RFC8196]
16 Reverse Metric y n n n [RFC8500]
17 IS-IS Area Node IDs TLV (TEMPORARY - registered 2019-08-08, extension registered 2020-06-19, expires 2021-08-08) n y n n [draft-ietf-lsr-dynamic-flooding]
18 IS-IS Flooding Path TLV (TEMPORARY - registered 2019-08-08, extension registered 2020-06-19, expires 2021-08-08) n y n n [draft-ietf-lsr-dynamic-flooding]
19 IS-IS Flooding Request TLV (TEMPORARY - registered 2019-08-08, extension registered 2020-06-19, expires 2021-08-08) y n n n [draft-ietf-lsr-dynamic-flooding]
20 Area Proxy (TEMPORARY - registered 2020-08-31, expires 2021-08-31) n y n n [draft-ietf-lsr-isis-area-proxy-03]
21 Unassigned
22 Extended IS reachability n y n n [RFC5305]
23 IS Neighbor Attribute n y n n [RFC5311]
24 IS Alias ID n y n n [RFC5311]
25 L2 Bundle Member Attributes n y n n [RFC8668]
26 Unassigned
27 SRv6 Locator (TEMPORARY - registered 2020-06-17, expires 2021-06-17) n y n n [draft-ietf-lsr-isis-srv6-extensions-08]
28-41 Unassigned
42 DECnet Phase IV y n n n DEC (ancient)
43-65 Unassigned
66 Lucent Proprietary n y n n
67-127 Unassigned
128 IP Int. Reach n y n n [RFC1195][RFC5302]
129 Prot. Supported y y n n [RFC1195]
130 IP Ext. Address n y n n [RFC1195][RFC5302]
131 IDRPI n y y n [RFC1195]
132 IP Intf. Address y y n n [RFC1195]
133 Illegal n n n n [RFC1195] (not used)
134 Traffic Engineering router ID n y n n [RFC5305]
135 Extended IP reachability n y n n [RFC5305]
136 Unassigned
137 Dynamic Name n y n y [RFC5301] [RFC6233]
138 GMPLS-SRLG n y n n [RFC5307]
139 IPv6 SRLG n y n n [RFC6119]
140 IPv6 TE Router ID n y n n [RFC6119]
141 inter-AS reachability information n y n n [RFC5316]
142 GADDR-TLV n y n n [RFC7176]
143 MT-Port-Cap-TLV y n n n [RFC6165]
144 MT-Capability TLV n y n n [RFC6329]
145 TRILL Neighbor TLV y n n n [RFC7176]
146 Unassigned
147 MAC-RI TLV n y n n [RFC6165]
148 BFD-Enabled TLV y n n n [RFC6213]
149 Segment Identifier / Label Binding n y n n [RFC8667]
150 Multi-Topology Segment Identifier / Label Binding n y n n [RFC8667]
151-160 Unassigned
161 Flood Reflection (TEMPORARY - registered 2020-08-05, expires 2021-08-05) y n n n [draft-ietf-lsr-isis-flood-reflection-01]
162-175 Unassigned
176 Nortel Proprietary n y n n
177 Nortel Proprietary n y n n
178-210 Unassigned
211 Restart TLV y n n n [RFC8706]
212-221 Unassigned
222 MT-ISN n y n n [RFC5120]
223 MT IS Neighbor Attribute n y n n [RFC5311]
224-228 Unassigned
229 M-Topologies y y n n [RFC5120]
230-231 Unassigned
232 IPv6 Intf. Addr. y y n n [RFC5308]
233 IPv6 Global Interface Address TLV y n n n [RFC6119]
234 Unassigned
235 MT IP. Reach n y n n [RFC5120]
236 IPv6 IP. Reach n y n n [RFC5308]
237 MT IPv6 IP. Reach n y n n [RFC5120]
238 Application-Specific SRLG n y n n [RFC8919]
239 Unassigned
240 P2P 3-Way Adj. State y n n n [RFC5303]
241 Unassigned
242 IS-IS Router CAPABILITY TLV n y n n [RFC7981]
243 Scope Flooding Support y n n n [RFC7356]
244-250 Unassigned
251 Generic Information n y n n [RFC6823]
252-65535 Unassigned

IS-IS Authentication Type Codes for TLV 10 (Authentication TLV)

Registration Procedure(s)
Expert Review
Expert(s)
Chris Hopps, Hannes Gredler, Les Ginsberg
Reference
[RFC5304]
Available Formats

CSV
Value Authentication Type Code Reference
0 Reserved [ISO 10589, "Intermediate System to Intermediate System Intra- Domain Routeing Exchange Protocol for use in Conjunction with the Protocol for Providing the Connectionless-mode Network Service (ISO 8473)", International Standard 10589: 2002, Second Edition, 2002.]
1 Cleartext Password [ISO 10589, "Intermediate System to Intermediate System Intra- Domain Routeing Exchange Protocol for use in Conjunction with the Protocol for Providing the Connectionless-mode Network Service (ISO 8473)", International Standard 10589: 2002, Second Edition, 2002.]
2 ISO 10589 Reserved [ISO 10589, "Intermediate System to Intermediate System Intra- Domain Routeing Exchange Protocol for use in Conjunction with the Protocol for Providing the Connectionless-mode Network Service (ISO 8473)", International Standard 10589: 2002, Second Edition, 2002.]
3 Cryptographic Authentication (CRYPTO_AUTH) [RFC5310]
4-53 Unassigned
54 HMAC-MD5 Authentication [RFC5304]
55-254 Unassigned
255 Routing Domain private authentication method [ISO 10589, "Intermediate System to Intermediate System Intra- Domain Routeing Exchange Protocol for use in Conjunction with the Protocol for Providing the Connectionless-mode Network Service (ISO 8473)", International Standard 10589: 2002, Second Edition, 2002.]

Sub-TLVs for TLV 16 (Reverse Metric TLV)

Registration Procedure(s)
Expert Review
Expert(s)
Chris Hopps, Hannes Gredler, Les Ginsberg
Reference
[RFC8500]
Available Formats

CSV
Type Description Reference
0 Reserved [RFC8500]
1-17 Unassigned
18 Traffic Engineering Metric [RFC8500, Section 2]
19-255 Unassigned

Sub-TLVs for TLVs 22, 23, 25, 141, 222, and 223 (Extended IS reachability, IS Neighbor Attribute, L2 Bundle Member Attributes, inter-AS reachability information, MT-ISN, and MT IS Neighbor Attribute TLVs)

Registration Procedure(s)
Expert Review
Expert(s)
Chris Hopps, Hannes Gredler, Les Ginsberg
Reference
[RFC5305][RFC5316][RFC7370][RFC8668]
Note
Allocations within this registry require documentation of the use of
the allocated value and approval by the Designated Expert assigned
by the IESG.
Note
The column for TLV 25 may be marked as follows:
      
y - sub-TLV may appear in TLV 25 but MUST NOT be shared by multiple 
    L2 Bundle Members
y(s) - sub-TLV may appear in TLV 25 and MAY be shared by multiple 
    L2 Bundle Members
n - sub-TLV MUST NOT appear in TLV 25
Available Formats

CSV
Type Description 22 23 25 141 222 223 Reference
0-2 Unassigned
3 Administrative group (color) y y y(s) y y y [RFC5305]
4 Link Local/Remote Identifiers y y y(s) y y y [RFC5307]
5 Unassigned
6 IPv4 interface address y y y(s) y y y [RFC5305]
7 Unassigned
8 IPv4 neighbor address y y y(s) y y y [RFC5305]
9 Maximum link bandwidth y y y(s) y y y [RFC5305]
10 Maximum reservable link bandwidth y y y(s) y y y [RFC5305]
11 Unreserved bandwidth y y y(s) y y y [RFC5305]
12 IPv6 Interface Address y y y(s) y y y [RFC6119]
13 IPv6 Neighbor Address y y y(s) y y y [RFC6119]
14 Extended Administrative Group y y y(s) y y y [RFC7308]
15 Link MSD y y y y y y [RFC8491]
16 Application-Specific Link Attributes y y y(s) y y y [RFC8919]
17 Unassigned
18 TE Default metric y y y(s) y y y [RFC5305]
19 Link-attributes y y y(s) y y y [RFC5029]
20 Link Protection Type y y y(s) y y y [RFC5307]
21 Interface Switching Capability Descriptor y y y(s) y y y [RFC5307]
22 Bandwidth Constraints y y y(s) y y y [RFC4124]
23 Unconstrained TE LSP Count (sub-)TLV y y y(s) y y y [RFC5330]
24 remote AS number n n n y n n [RFC5316]
25 IPv4 remote ASBR Identifier n n n y n n [RFC5316]
26 IPv6 remote ASBR Identifier n n n y n n [RFC5316]
27 Interface Adjustment Capability Descriptor (IACD) y y y(s) y y y [RFC6001]
28 MTU y y n n y y [RFC7176]
29 SPB-Metric y y y(s) n y y [RFC6329]
30 SPB-A-OALG y y y(s) n y y [RFC6329]
31 Adjacency Segment Identifier y y n y y y [RFC8667]
32 LAN Adjacency Segment Identifier y y n y y y [RFC8667]
33 Unidirectional Link Delay y y y y y y [RFC8570]
34 Min/Max Unidirectional Link Delay y y y y y y [RFC8570]
35 Unidirectional Delay Variation y y y y y y [RFC8570]
36 Unidirectional Link Loss y y y y y y [RFC8570]
37 Unidirectional Residual Bandwidth y y y y y y [RFC8570]
38 Unidirectional Available Bandwidth y y y y y y [RFC8570]
39 Unidirectional Utilized Bandwidth y y y y y y [RFC8570]
40 RTM Capability y y n n y y [RFC8169]
41 L2 Bundle Member Adj-SID n n y n n n [RFC8668]
42 L2 Bundle Member LAN Adj-SID n n y n n n [RFC8668]
43 SRv6 End.X SID (TEMPORARY - registered 2020-06-17, expires 2021-06-17) y y y y y y [draft-ietf-lsr-isis-srv6-extensions-08]
44 SRv6 LAN End.X SID (TEMPORARY - registered 2020-06-17, expires 2021-06-17) y y y y y y [draft-ietf-lsr-isis-srv6-extensions-08]
45-160 Unassigned
161 Flood Reflector Adjacency (TEMPORARY - registered 2020-08-05, expires 2021-08-05) y y n y y y [draft-ietf-lsr-isis-flood-reflection-01]
162-249 Unassigned
250-254 Reserved for Cisco-specific extensions
255 Reserved for future expansion

link-attribute bit values for sub-TLV 19 of TLV 22 (Extended IS reachability TLV)

Registration Procedure(s)
Standards Action
Reference
[RFC5029]
Available Formats

CSV
Value Name Reference
0x1 Local Protection Available [RFC5029]
0x2 Link Excluded from Local Protection [RFC5029]
0x4 Local Edge Enabled for Flooding (LEEF) (TEMPORARY - registered 2019-08-08, extension registered 2020-06-19, expires 2021-08-08) [draft-ietf-lsr-dynamic-flooding]

Sub-TLVs for TLVs 135, 235, 236, and 237 (Extended IP reachability, MT IP. Reach, IPv6 IP. Reach, and MT IPv6 IP. Reach TLVs)

Registration Procedure(s)
Expert Review
Expert(s)
Chris Hopps, Hannes Gredler, Les Ginsberg
Reference
[RFC5305][RFC7370]
Note
Allocations within this registry require documentation of the use of
the allocated value and approval by the Designated Expert assigned
by the IESG.
Available Formats

CSV
Type Description 135 235 236 237 Reference
0 Unassigned
1 32-bit Administrative Tag Sub-TLV y y y y [RFC5130]
2 64-bit Administrative Tag Sub-TLV y y y y [RFC5130]
3 Prefix Segment Identifier y y y y [RFC8667]
4 Prefix Attribute Flags y y y y [RFC7794]
5 SRv6 End SID (TEMPORARY - registered 2020-06-17, expires 2021-06-17) n n n n [draft-ietf-lsr-isis-srv6-extensions-08]
6 Flex-Algorithm Prefix Metric (TEMPORARY - registered 2019-10-02, extension registered 2020-08-12, expires 2021-10-02) y y y y [draft-ietf-lsr-flex-algo]
7-10 Unassigned
11 IPv4 Source Router ID y y y y [RFC7794]
12 IPv6 Source Router ID y y y y [RFC7794]
13-31 Unassigned
32 BIER Info y y y y [RFC8401]
33-255 Unassigned

Bit Values for Prefix Attribute Flags Sub-TLV

Registration Procedure(s)
Expert Review
Expert(s)
Chris Hopps, Hannes Gredler, Les Ginsberg
Reference
[RFC7794]
Available Formats

CSV
Bit # Name Reference
0 External Prefix Flag (X-flag) [RFC7794]
1 Re-advertisement Flag (R-flag) [RFC7794]
2 Node Flag (N-flag) [RFC7794]
3 ELC Flag (E-flag) [RFC-ietf-isis-mpls-elc-13]
4 A bit (TEMPORARY - registered 2020-06-17, expires 2021-06-17) [draft-ietf-lsr-isis-srv6-extensions-08]

IS-IS Group Address Type Codes for TLV 142 (GADDR-TLV)

Registration Procedure(s)
Expert Review
Expert(s)
Chris Hopps, Hannes Gredler, Les Ginsberg
Reference
[RFC7176]
Available Formats

CSV
Type Description Reference
0 Reserved [RFC7176]
1 GMAC-ADDR [RFC7176]
2 GIP-ADDR [RFC7176]
3 GIPV6-ADDR [RFC7176]
4 GLMAC-ADDR [RFC7176]
5 GLIP-ADDR [RFC7176]
6 GLIPV6-ADDR [RFC7176]
7-254 Unassigned
255 Reserved [RFC7176]

Sub-TLVs for TLV 143 (MT-Port-Cap-TLV)

Registration Procedure(s)
Expert Review
Expert(s)
Chris Hopps, Hannes Gredler, Les Ginsberg
Reference
[RFC7176]
Available Formats

CSV
Value Group Address Type Code Reference
0 Reserved [RFC7176]
1 VLAN-FLAGs [RFC7176]
2 Enabled-VLANs [RFC7176]
3 AppointedFwrdrs [RFC7176]
4 SPB-MCID [RFC6329]
5 SPB-Digest [RFC6329]
6 SPB-B-VID [RFC6329]
7 PORT-TRILL-VER [RFC7176]
8 VLANs-Appointed [RFC7176]
9-254 Unassigned
255 Reserved [RFC7176]

Sub-TLVs for TLV 144 (MT-Capability TLV)

Registration Procedure(s)
Expert Review
Expert(s)
Chris Hopps, Hannes Gredler, Les Ginsberg
Reference
[RFC6329]
Available Formats

CSV
Value Group Address Type Code Reference
0 Reserved [RFC6329]
1 SPB-Inst [RFC6329]
2 SPB-I-OALG [RFC6329]
3 SPBM-SI [RFC6329]
4 SPBV-ADDR [RFC6329]
5 Unassigned
6 NICKNAME [RFC7176]
7 TREES [RFC7176]
8 TREE-RT-IDs [RFC7176]
9 TREE-USE-IDs [RFC7176]
10 INT-VLAN [RFC7176]
11-12 Unassigned
13 TRILL-VER [RFC7176]
14 VLAN-GROUP [RFC7176]
15 INT-LABEL [RFC7176]
16 RBCHANNELS [RFC7176]
17 AFFINITY [RFC7176]
18 LABEL-GROUP [RFC7176]
19-20 Unassigned
21 Topology sub-TLV [RFC7813]
22 Hop sub-TLV [RFC7813]
23 Bandwidth Constraint sub-TLV [RFC7813]
24 Bandwidth Assignment sub-TLV [RFC7813]
25 Timestamp sub-TLV [RFC7813]
26-254 Unassigned
255 Reserved [RFC6329]

Sub-TLVs for TLV 242 (IS-IS Router CAPABILITY TLV)

Registration Procedure(s)
Expert Review
Expert(s)
Chris Hopps, Hannes Gredler, Les Ginsberg
Reference
[RFC7981]
Note
Allocations within this registry require documentation of the use of
the allocated value and approval by the Designated Expert assigned
by the IESG.
Available Formats

CSV
Value Description Reference
0 Reserved
1 TE Node Capability Descriptor [RFC5073]
2 Segment Routing Capability [RFC8667]
3 TE-MESH-GROUP TLV (IPv4) [RFC4972]
4 TE-MESH-GROUP TLV (IPv6) [RFC4972]
5 PCED sub-TLV [RFC5089]
6 NICKNAME [RFC7176]
7 TREES [RFC7176]
8 TREE-RT-IDs [RFC7176]
9 TREE-USE-IDs [RFC7176]
10 INT-VLAN [RFC7176]
11 IPv4 TE Router ID [RFC5316]
12 IPv6 TE Router ID [RFC5316]
13 TRILL-VER [RFC7176]
14 VLAN-GROUP [RFC7176]
15 INT-LABEL [RFC7176]
16 RBCHANNELS [RFC7176]
17 AFFINITY [RFC7176]
18 LABEL-GROUP [RFC7176]
19 Segment Routing Algorithm [RFC8667]
20 S-BFD Discriminators [RFC7883]
21 Node-Admin-Tag [RFC7917]
22 Segment Routing Local Block (SRLB) [RFC8667]
23 Node MSD [RFC8491]
24 Segment Routing Mapping Server Preference (SRMS Preference) [RFC8667]
25 SRv6 Capabilities (TEMPORARY - registered 2020-06-17, expires 2021-06-17) [draft-ietf-lsr-isis-srv6-extensions-08]
26 Flexible Algorithm Definition (TEMPORARY - registered 2018-06-04, extension registered 2020-05-12, expires 2021-06-04) [draft-ietf-lsr-flex-algo]
27 IS-IS Area Leader Sub-TLV (TEMPORARY - registered 2019-08-08, extension registered 2020-06-19, expires 2021-08-08) [draft-ietf-lsr-dynamic-flooding]
28 IS-IS Dynamic Flooding Sub-TLV (TEMPORARY - registered 2019-08-08, extension registered 2020-06-19, expires 2021-08-08) [draft-ietf-lsr-dynamic-flooding]
29-160 Unassigned
161 Flood Reflection Discovery (TEMPORARY - registered 2020-08-05, expires 2021-08-05) [draft-ietf-lsr-isis-flood-reflection-01]
162-255 Unassigned

Application Identifiers for TLV 251 (Generic Information TLV)

Registration Procedure(s)
Expert Review
Expert(s)
Chris Hopps, Hannes Gredler, Les Ginsberg
Reference
[RFC6823]
Available Formats

CSV
ID Value Description Allowed in Instance zero (y/n) Reference
0 Reserved [RFC6823]
1 TRILL n [RFC7357]
2-65535 Unassigned

sub-sub-TLVs for BIER Info sub-TLV

Registration Procedure(s)
Expert Review
Expert(s)
Chris Hopps, Les Ginsberg
Reference
[RFC8401]
Available Formats

CSV
Type Name Reference
0 Unassigned
1 BIER MPLS Encapsulation [RFC8401]
2-255 Unassigned

Sub-TLVs for TLVs 149 and 150

Registration Procedure(s)
Expert Review
Expert(s)
Unassigned
Reference
[RFC8667]
Available Formats

CSV
Type Description Reference
0 Reserved [RFC8667]
1 SID/Label [RFC8667]
2 Unassigned
3 Prefix Segment Identifier [RFC8667]
4-255 Unassigned

Sub-sub-TLV Codepoints for Application-Specific Link Attributes

Registration Procedure(s)
Expert Review
Expert(s)
Unassigned
Reference
[RFC8919]
Note
For future codepoints, in cases where the document that defines
the encoding is different from the document that assigns
the codepoint, the encoding reference MUST be to the document
that defines the encoding.
Note
If a link attribute can be advertised both as a sub-TLV of TLVs
22, 23, 25, 141, 222, and 223 and as a sub-sub-TLV of the 
Application-Specific Link Attributes sub-TLV defined in 
[RFC8919], then the same numerical code
should be assigned to the link attribute whenever possible.
Available Formats

CSV

Sub-TLVs for TLV 238

Registration Procedure(s)
Expert Review
Expert(s)
Unassigned
Reference
[RFC8919]
Note
For future codepoints, in cases where the document that defines
the encoding is different from the document that assigns the 
codepoint, the encoding reference MUST be to the document that 
defines the encoding.
Available Formats

CSV
Value Description Reference
0-3 Unassigned
4 Link Local/Remote Identifiers [RFC5307]
5 Unassigned
6 IPv4 interface address [RFC5305]
7 Unassigned
8 IPv4 neighbor address [RFC5305]
9-11 Unassigned
12 IPv6 Interface Address [RFC6119]
13 IPv6 Neighbor Address [RFC6119]
14-255 Unassigned