User Datagram Protocol (UDP)

Registries Included Below

UDP Option Kind Numbers

Registration Procedure(s)

Standards Action or IESG Approval

Reference

[RFC9868]

Note

Codepoints 0-7 MUST be supported on 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)	[RFC9868]
1	-	No Operation (NOP)	[RFC9868]
2	6	Additional Payload Checksum (APC)	[RFC9868]
3	10/12	Fragmentation (FRAG)	[RFC9868]
4	4	Maximum Datagram Size (MDS)	[RFC9868]
5	5	Maximum Reassembled Datagram Size (MRDS)	[RFC9868]
6	6	Request (REQ)	[RFC9868]
7	6	Response (RES)	[RFC9868]
8	10	Timestamp (TIME)	[RFC9868]
9	(varies)	RESERVED for Authentication (AUTH)	[RFC9868][draft-touch-tsvwg-udp-auth-opt-00]
10-126	(varies)	Unassigned
127	(varies)	[RFC3692]-style experiments (EXP)	[RFC9868]
128-191		Reserved	[RFC9868]
192	(varies)	Reserved for UNSAFE Compression (UCMP)	[RFC9868]
193	(varies)	Reserved for UNSAFE Encryption (UENC)	[RFC9868]
194-253		Unassigned - UNSAFE
254	(varies)	[RFC3692]-style UNSAFE experiments (UEXP)	[RFC9868]
255		Reserved - UNSAFE	[RFC9868]

Reference

[RFC6994][RFC9868]

Note

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