Value	Name	Reference
0x000	Reserved	[RFC8489]
0x001	Binding	[RFC8489]
0x002	Reserved; was SharedSecret prior to [RFC5389]	[RFC8489]
0x003	Allocate	[RFC8656]
0x004	Refresh	[RFC8656]
0x005	Unassigned
0x006	Send	[RFC8656]
0x007	Data	[RFC8656]
0x008	CreatePermission	[RFC8656]
0x009	ChannelBind	[RFC8656]
0x00A	Connect	[RFC6062]
0x00B	ConnectionBind	[RFC6062]
0x00C	ConnectionAttempt	[RFC6062]
0x00D-0x07F	Unassigned
0x080	GOOG-PING	[Jonas_Oreland]
0x081-0x0FF	Unassigned
0x100-0xFFF	Reserved (For DTLS-SRTP multiplexing collision avoidance, see [RFC7983]. Cannot be made available for assignment without IETF Review.)	[RFC7983]

Range	Registration Procedures	Note
0x0000-0x3FFF	IETF Review	comprehension-required range
0x4000-0x7FFF	Expert Review	comprehension-required range
0x8000-0xBFFF	IETF Review	comprehension-optional range
0xC000-0xFFFF	Expert Review	comprehension-optional range

Value	Name	Reference
0x0000	Reserved	[RFC8489]
0x0001	MAPPED-ADDRESS	[RFC8489]
0x0002	Reserved; was RESPONSE-ADDRESS prior to [RFC5389]	[RFC8489]
0x0003	Reserved; was CHANGE-REQUEST prior to [RFC5389]	[RFC5780][RFC Errata 4233]
0x0004	Reserved; was SOURCE-ADDRESS prior to [RFC5389]	[RFC8489]
0x0005	Reserved; was CHANGED-ADDRESS prior to [RFC5389]	[RFC8489]
0x0006	USERNAME	[RFC8489]
0x0007	Reserved; was PASSWORD prior to [RFC5389]	[RFC8489]
0x0008	MESSAGE-INTEGRITY	[RFC8489]
0x0009	ERROR-CODE	[RFC8489]
0x000A	UNKNOWN-ATTRIBUTES	[RFC8489]
0x000B	Reserved; was REFLECTED-FROM prior to [RFC5389]	[RFC8489]
0x000C	CHANNEL-NUMBER	[RFC8656]
0x000D	LIFETIME	[RFC8656]
0x000E-0x000F	Reserved
0x0010	Reserved (was BANDWIDTH)	[RFC8656]
0x0011	Reserved
0x0012	XOR-PEER-ADDRESS	[RFC8656]
0x0013	DATA	[RFC8656]
0x0014	REALM	[RFC8489]
0x0015	NONCE	[RFC8489]
0x0016	XOR-RELAYED-ADDRESS	[RFC8656]
0x0017	REQUESTED-ADDRESS-FAMILY	[RFC8656]
0x0018	EVEN-PORT	[RFC8656]
0x0019	REQUESTED-TRANSPORT	[RFC8656]
0x001A	DONT-FRAGMENT	[RFC8656]
0x001B	ACCESS-TOKEN	[RFC7635]
0x001C	MESSAGE-INTEGRITY-SHA256	[RFC8489]
0x001D	PASSWORD-ALGORITHM	[RFC8489]
0x001E	USERHASH	[RFC8489]
0x001F-0x001F	Unassigned
0x0020	XOR-MAPPED-ADDRESS	[RFC8489]
0x0021	Reserved (was TIMER-VAL)	[RFC8656]
0x0022	RESERVATION-TOKEN	[RFC8656]
0x0023	Reserved
0x0024	PRIORITY	[RFC8445]
0x0025	USE-CANDIDATE	[RFC8445]
0x0026	PADDING	[RFC5780]
0x0027	RESPONSE-PORT	[RFC5780]
0x0028-0x0029	Reserved
0x002A	CONNECTION-ID	[RFC6062]
0x002B-0x002F	Unassigned
0x0030	Reserved
0x0031-0x7FFF	Unassigned
0x8000	ADDITIONAL-ADDRESS-FAMILY	[RFC8656]
0x8001	ADDRESS-ERROR-CODE	[RFC8656]
0x8002	PASSWORD-ALGORITHMS	[RFC8489]
0x8003	ALTERNATE-DOMAIN	[RFC8489]
0x8004	ICMP	[RFC8656]
0x8005-0x8021	Unassigned
0x8022	SOFTWARE	[RFC8489]
0x8023	ALTERNATE-SERVER	[RFC8489]
0x8024	Reserved
0x8025	TRANSACTION_TRANSMIT_COUNTER	[RFC7982]
0x8026	Reserved
0x8027	CACHE-TIMEOUT	[RFC5780]
0x8028	FINGERPRINT	[RFC8489]
0x8029	ICE-CONTROLLED	[RFC8445]
0x802A	ICE-CONTROLLING	[RFC8445]
0x802B	RESPONSE-ORIGIN	[RFC5780]
0x802C	OTHER-ADDRESS	[RFC5780]
0x802D	ECN-CHECK STUN	[RFC6679]
0x802E	THIRD-PARTY-AUTHORIZATION	[RFC7635]
0x802F	Unassigned
0x8030	MOBILITY-TICKET	[RFC8016]
0x8031-0xBFFF	Unassigned
0xC000	CISCO-STUN-FLOWDATA	[Dan_Wing]
0xC001	ENF-FLOW-DESCRIPTION	[Pål_Erik_Martinsen]
0xC002	ENF-NETWORK-STATUS	[Pål_Erik_Martinsen]
0xC003	CISCO-WEBEX-FLOW-INFO	[Stefano_Giorcelli]
0xC004-0xC055	Unassigned
0xC056	CITRIX-TRANSACTION-ID	[Paras_Babbar]
0xC057	GOOG-NETWORK-INFO	[Jonas_Oreland]
0xC058	GOOG-LAST-ICE-CHECK-RECEIVED	[Jonas_Oreland]
0xC059	GOOG-MISC-INFO	[Jonas_Oreland]
0xC05A	GOOG-OBSOLETE-1	[Jonas_Oreland]
0xC05B	GOOG-CONNECTION-ID	[Jonas_Oreland]
0xC05C	GOOG-DELTA	[Jonas_Oreland]
0xC05D	GOOG-DELTA-ACK	[Jonas_Oreland]
0xC05E	GOOG-DELTA-SYNC-REQ	[Jonas_Oreland]
0xC05F	Unassigned
0xC060	GOOG-MESSAGE-INTEGRITY-32	[Jonas_Oreland]
0xC061-0xC06F	Unassigned
0xC070	META-DTLS-IN-STUN	[Philipp_Hancke]
0xC071	META-DTLS-IN-STUN-ACKNOWLEDGEMENT	[Philipp_Hancke]
0xC072-0xFFFF	Unassigned

Value	Name	Reference
0-299	Reserved
300	Try Alternate	[RFC8489]
301-399	Unassigned
400	Bad Request	[RFC8489]
401	Unauthenticated	[RFC8489]
402	Unassigned
403	Forbidden	[RFC8656]
404	Unassigned
405	Mobility Forbidden	[RFC8016]
406-419	Unassigned
420	Unknown Attribute	[RFC8489]
421-436	Unassigned
437	Allocation Mismatch	[RFC8656]
438	Stale Nonce	[RFC8489]
439	Unassigned
440	Address Family not Supported	[RFC8656]
441	Wrong Credentials	[RFC8656]
442	Unsupported Transport Protocol	[RFC8656]
443	Peer Address Family Mismatch	[RFC8656]
444-445	Unassigned
446	Connection Already Exists	[RFC6062]
447	Connection Timeout or Failure	[RFC6062]
448-485	Unassigned
486	Allocation Quota Reached	[RFC8656]
487	Role Conflict	[RFC8445]
488-499	Unassigned
500	Server Error	[RFC8489]
501-507	Unassigned
508	Insufficient Capacity	[RFC8656]
509-699	Unassigned

Bit	Name	Reference
0	Password algorithms	[RFC8489]
1	Username anonymity	[RFC8489]
2-23	Unassigned

ID	Name	Contact URI	Last Updated
[Dan_Wing]	Dan Wing	mailto:danwing&gmail.com	2022-10-14
[Jonas_Oreland]	Jonas Oreland	mailto:jonaso&google.com	2023-03-20
[Pål_Erik_Martinsen]	Pål-Erik Martinsen	mailto:palmarti&cisco.com	2016-04-20
[Paras_Babbar]	Paras Babbar	mailto:Paras.Babbar&cloud.com	2023-12-18
[Philipp_Hancke]	Philipp Hancke	mailto:phancke&meta.com	2024-12-20
[Stefano_Giorcelli]	Stefano Giorcelli	mailto:stefanog&cisco.com	2023-12-07

Session Traversal Utilities for NAT (STUN) Parameters

STUN Methods

STUN Attributes

STUN Error Codes

Traversal Using Relays around NAT (TURN) Channel Numbers

STUN Security Features

STUN Password Algorithms

Contact Information