RFC 4379 - 7. IANA Considerations
7. IANA Considerations
The TCP and UDP port number 3503 has been allocated by IANA for LSP echo requests and replies.
The following sections detail the new name spaces to be managed by IANA. For each of these name spaces, the space is divided into assignment ranges; the following terms are used in describing the procedures by which IANA allocates values: "Standards Action" (as defined in [IANA]), "Specification Required", and "Vendor Private Use".
Values from "Specification Required" ranges MUST be registered with IANA. The request MUST be made via an Experimental RFC that describes the format and procedures for using the code point; the actual assignment is made during the IANA actions for the RFC.
Values from "Vendor Private" ranges MUST NOT be registered with IANA; however, the message MUST contain an enterprise code as registered with the IANA SMI Private Network Management Private Enterprise Numbers. For each name space that has a Vendor Private range, it must be specified where exactly the SMI Private Enterprise Number resides; see below for examples. In this way, several enterprises (vendors) can use the same code point without fear of collision.
7.1. Message Types, Reply Modes, Return Codes
The IANA has created and will maintain registries for Message Types, Reply Modes, and Return Codes. Each of these can take values in the range 0-255. Assignments in the range 0-191 are via Standards Action; assignments in the range 192-251 are made via "Specification Required"; values in the range 252-255 are for Vendor Private Use, and MUST NOT be allocated.
If any of these fields fall in the Vendor Private range, a top-level Vendor Enterprise Number TLV MUST be present in the message.
Message Types defined in this document are the following:
Value Meaning
----- -------
1 MPLS echo request
2 MPLS echo reply
Reply Modes defined in this document are the following:
Value Meaning
----- -------
1 Do not reply
2 Reply via an IPv4/IPv6 UDP packet
3 Reply via an IPv4/IPv6 UDP packet with Router Alert
4 Reply via application level control channel
Return Codes defined in this document are listed in section 3.1.
7.2. TLVs
The IANA has created and will maintain a registry for the Type field of top-level TLVs as well as for any associated sub-TLVs. Note the meaning of a sub-TLV is scoped by the TLV. The number spaces for the sub-TLVs of various TLVs are independent.
The valid range for TLVs and sub-TLVs is 0-65535. Assignments in the range 0-16383 and 32768-49161 are made via Standards Action as defined in [IANA]; assignments in the range 16384-31743 and 49162-64511 are made via "Specification Required" as defined above; values in the range 31744-32767 and 64512-65535 are for Vendor Private Use, and MUST NOT be allocated.
If a TLV or sub-TLV has a Type that falls in the range for Vendor Private Use, the Length MUST be at least 4, and the first four octets MUST be that vendor's SMI Private Enterprise Number, in network octet order. The rest of the Value field is private to the vendor.
TLVs and sub-TLVs defined in this document are the following:
Type Sub-Type Value Field
---- -------- -----------
1 Target FEC Stack
1 LDP IPv4 prefix
2 LDP IPv6 prefix
3 RSVP IPv4 LSP
4 RSVP IPv6 LSP
5 Not Assigned
6 VPN IPv4 prefix
7 VPN IPv6 prefix
8 L2 VPN endpoint
9 "FEC 128" Pseudowire (Deprecated)
10 "FEC 128" Pseudowire
11 "FEC 129" Pseudowire
12 BGP labeled IPv4 prefix
13 BGP labeled IPv6 prefix
14 Generic IPv4 prefix
15 Generic IPv6 prefix
16 Nil FEC
2 Downstream Mapping
3 Pad
4 Not Assigned
5 Vendor Enterprise Number
6 Not Assigned
7 Interface and Label Stack
8 Not Assigned
9 Errored TLVs
Any value The TLV not understood
10 Reply TOS Byte