User Datagram Protocol (UDP)

Registries included below

UDP Option Kind Numbers

Registration Procedure(s)

Standards Action or IESG Approval

Reference

[RFC-ietf-tsvwg-udp-options-45]

Note

Code points 0-7 MUST be supported an any implementation supporting 
UDP options. All others are supported at the discretion of each 
implementation.

Available Formats

CSV

Kind	Length	Meaning	Reference
0	-	End of Options List (EOL)	[RFC-ietf-tsvwg-udp-options-45]
1	-	No operation (NOP)	[RFC-ietf-tsvwg-udp-options-45]
2	6	Additional payload checksum (APC)	[RFC-ietf-tsvwg-udp-options-45]
3	10/12	Fragmentation (FRAG)	[RFC-ietf-tsvwg-udp-options-45]
4	4	Maximum datagram size (MDS)	[RFC-ietf-tsvwg-udp-options-45]
5	5	Maximum reassembled datagram size (MRDS)	[RFC-ietf-tsvwg-udp-options-45]
6	6	Request (REQ)	[RFC-ietf-tsvwg-udp-options-45]
7	6	Response (RES)	[RFC-ietf-tsvwg-udp-options-45]
8	10	Timestamps (TIME)	[RFC-ietf-tsvwg-udp-options-45]
9	(varies)	Reserved for Authentication (AUTH)	[RFC-ietf-tsvwg-udp-options-45][draft-touch-tsvwg-udp-auth-opt-00]
10-126	(varies)	Unassigned
127	(varies)	[RFC3692]-style experiments (EXP)	[RFC-ietf-tsvwg-udp-options-45]
128-191		Reserved	[RFC-ietf-tsvwg-udp-options-45]
192	(varies)	Reserved for Compression (UCMP)	[RFC-ietf-tsvwg-udp-options-45]
193	(varies)	Reserved for Encryption (UENC)	[RFC-ietf-tsvwg-udp-options-45]
194-253		Unassigned - UNSAFE
254	(varies)	[RFC3692]-style experiments (UEXP)	[RFC-ietf-tsvwg-udp-options-45]
255		Reserved - UNSAFE	[RFC-ietf-tsvwg-udp-options-45]

Reference

[RFC6994][RFC-ietf-tsvwg-udp-options-45]

Note

See [https://www.iana.org/assignments/tcp-parameters/tcp-parameters.xhtml#tcp-udp-exids].