Internet Assigned Numbers Authority Datagram Congestion Control Protocol (DCCP) Parameters Created 2005-08-25 Last Updated 2025-04-21 Available Formats [IMG] XML [IMG] HTML [IMG] Plain text Registries included below • Packet Types • Reset Codes • Option Types • Feature Numbers • Congestion Control Identifiers • Ack Vector States • Drop Codes • Service Codes • MP-DCCP Versions • Multipath Options • Multipath Key Type Packet Types Registration Procedure(s) Standards Action Reference [RFC4340] Available Formats [IMG] CSV Type Description/Meaning Reference 0 DCCP-Request [RFC4340] 1 DCCP-Response [RFC4340] 2 DCCP-Data [RFC4340] 3 DCCP-Ack [RFC4340] 4 DCCP-DataAck [RFC4340] 5 DCCP-CloseReq [RFC4340] 6 DCCP-Close [RFC4340] 7 DCCP-Reset [RFC4340] 8 DCCP-Sync [RFC4340] 9 DCCP-SyncAck [RFC4340] 10 DCCP-Listen [RFC5596] 11-13 Unassigned [RFC4340] 14 Reserved for experimental and testing use [RFC4340] 15 Unassigned [RFC4340] Reset Codes Reference [RFC4340] Available Formats [IMG] CSV Range Registration Procedures Note 12-119 IETF Review (IETF RFC publication) 120-126 Reserved For experimental and testing use 127 IETF Review (IETF RFC publication) 128-255 CCID-specific codes [1] Reset Code Name Reference 0 Unspecified [RFC4340] 1 Closed [RFC4340] 2 Aborted [RFC4340] 3 No Connection [RFC4340] 4 Packet Error [RFC4340] 5 Option Error [RFC4340] 6 Mandatory Error [RFC4340] 7 Connection Refused [RFC4340] 8 Bad Service Code [RFC4340] 9 Too Busy [RFC4340] 10 Bad Init Cookie [RFC4340] 11 Aggression Penalty [RFC4340] 12 Encapsulated Port Reuse [RFC6773] 13 Abrupt MP termination [RFC-ietf-tsvwg-multipath-dccp-23] 14-119 Unassigned [RFC4340] 120-126 Reserved [RFC4340] 127 Unassigned [RFC4340] 128-255 CCID-specific codes [RFC4340] Option Types Reference [RFC4340] Available Formats [IMG] CSV Range Registration Procedures Note 3-30 IETF Review (IETF RFC publication) 45-119 IETF Review (IETF RFC publication) 120-126 Reserved For experimental and testing use 127 IETF Review (IETF RFC publication) 128-255 CCID-specific codes [1] Type Description/Meaning Reference 0 Padding [RFC4340] 1 Mandatory [RFC4340] 2 Slow Receiver [RFC4340] 3-30 Unassigned [RFC4340] 31 Reserved for experimental and testing use [RFC4340] 32 Change L [RFC4340] 33 Confirm L [RFC4340] 34 Change R [RFC4340] 35 Confirm R [RFC4340] 36 Init Cookie [RFC4340] 37 NDP Count [RFC4340] 38 Ack Vector [Nonce 0] [RFC4340] 39 Ack Vector [Nonce 1] [RFC4340] 40 Data Dropped [RFC4340] 41 Timestamp [RFC4340] 42 Timestamp Echo [RFC4340] 43 Elapsed Time [RFC4340] 44 Data Checksum [RFC4340] 45 Quick-Start Response [RFC5634] 46 Multipath [RFC-ietf-tsvwg-multipath-dccp-23] 47-119 Unassigned [RFC4340] 120-126 Reserved [RFC4340] 127 Unassigned [RFC4340] 128-255 CCID-specific codes [RFC4340] Feature Numbers Reference [RFC4340] Available Formats [IMG] CSV Range Registration Procedures Note 10-119 IETF Review (IETF RFC publication) 120-126 Reserved For experimental and testing use 127 IETF Review (IETF RFC publication) 128-255 CCID-specific codes [1] Number Description/Meaning Reference 0 Reserved [RFC4340] 1 Congestion Control ID (CCID) [RFC4340] 2 Allow Short Seqnos [RFC4340] 3 Sequence Window [RFC4340] 4 ECN Incapable [RFC4340] 5 Ack Ratio [RFC4340] 6 Send Ack Vector [RFC4340] 7 Send NDP Count [RFC4340] 8 Minimum Checksum Coverage [RFC4340] 9 Check Data Checksum [RFC4340] 10 Multipath Capable [RFC-ietf-tsvwg-multipath-dccp-23] 11-119 Unassigned [RFC4340] 120-126 Reserved [RFC4340] 127 Unassigned [RFC4340] 128-255 CCID-specific codes [RFC4340] Congestion Control Identifiers Reference [RFC4340] Available Formats [IMG] CSV Range Registration Procedures Note 0-1 IETF Review (IETF RFC publication) 4-247 IETF Review (IETF RFC publication) 248-254 Reserved For experimental and testing use 255 IETF Review (IETF RFC publication) CCID Description/Meaning Reference 0-1 Unassigned [RFC4340] 2 TCP-like Congestion Control [RFC4341] 3 TFRC Congestion Control [RFC4342] 4 TCP-Friendly Rate Control for Small Packets [RFC5622] 5-247 Unassigned [RFC4340] 248-254 Reserved [RFC4340] 255 Unassigned [RFC4340] Ack Vector States Registration Procedure(s) Standards Action Reference [RFC4340] Available Formats [IMG] CSV State Description/Meaning Reference 0 Received [RFC4340] 1 Received ECN Marked [RFC4340] 2 Unassigned [RFC4340] 3 Not Yet Received [RFC4340] Drop Codes Registration Procedure(s) Standards Action Reference [RFC4340] Available Formats [IMG] CSV Drop Code Description/Meaning Reference 0 Protocol Constraints [RFC4340] 1 Application Not Listening [RFC4340] 2 Receive Buffer [RFC4340] 3 Corrupt [RFC4340] 4-6 Unassigned [RFC4340] 7 Delivered Corrupt [RFC4340] Service Codes Reference [RFC4340] Note Service Codes can be found at the following: http://www.iana.org/assignments/service-codes MP-DCCP Versions Registration Procedure(s) RFC Required Reference [RFC-ietf-tsvwg-multipath-dccp-23] Available Formats [IMG] CSV Version Value Reference 0 0000 [RFC-ietf-tsvwg-multipath-dccp-23] 1-15 Unassigned Multipath Options Registration Procedure(s) RFC Required Reference [RFC-ietf-tsvwg-multipath-dccp-23] Available Formats [IMG] CSV Multipath Option Name Description Reference MP_OPT=0 MP_CONFIRM Confirm reception/processing of an MP_OPT option [RFC-ietf-tsvwg-multipath-dccp-23, Section 3.2.1] MP_OPT=1 MP_JOIN Join subflow to existing MP-DCCP connection [RFC-ietf-tsvwg-multipath-dccp-23, Section 3.2.2] MP_OPT=2 MP_FAST_CLOSE Close MP-DCCP connection [RFC-ietf-tsvwg-multipath-dccp-23, Section 3.2.3] MP_OPT=3 MP_KEY Exchange key material for MP_HMAC [RFC-ietf-tsvwg-multipath-dccp-23, Section 3.2.4] MP_OPT=4 MP_SEQ Multipath sequence number [RFC-ietf-tsvwg-multipath-dccp-23, Section 3.2.5] MP_OPT=5 MP_HMAC Hash-based message auth. code for MP-DCCP [RFC-ietf-tsvwg-multipath-dccp-23, Section 3.2.6] MP_OPT=6 MP_RTT Transmit RTT values and calculation parameters [RFC-ietf-tsvwg-multipath-dccp-23, Section 3.2.7] MP_OPT=7 MP_ADDADDR Advertise additional address(es)/port(s) [RFC-ietf-tsvwg-multipath-dccp-23, Section 3.2.8] MP_OPT=8 MP_REMOVEADDR Remove address(es)/ port(s) [RFC-ietf-tsvwg-multipath-dccp-23, Section 3.2.9] MP_OPT=9 MP_PRIO Change subflow priority [RFC-ietf-tsvwg-multipath-dccp-23, Section 3.2.10] MP_OPT=10 MP_CLOSE Close MP-DCCP subflow [RFC-ietf-tsvwg-multipath-dccp-23, Section 3.2.11] MP_OPT=11 MP_EXP Experimental suboption for private use [RFC-ietf-tsvwg-multipath-dccp-23, Section 3.2.12] MP_OPT>11 Unassigned Reserved for future Multipath Options Multipath Key Type Registration Procedure(s) RFC Required Reference [RFC-ietf-tsvwg-multipath-dccp-23] Available Formats [IMG] CSV Type Name Meaning Reference 0 Plain Text Plain text key [RFC-ietf-tsvwg-multipath-dccp-23, Section 3.2.4] 3-254 Unassigned Reserved for future use 255 Experimental For private use only [RFC-ietf-tsvwg-multipath-dccp-23, Section 3.2.4] Footnote [1] Note for CCID-specific codes: DCCP Reset Codes 128-255, Option Types 128-255, and Feature Numbers 128-255 are reserved for CCID-specific use. Each DCCP CCID (that is, each entry in the DCCP Congestion Control Identifiers registry) may create registries for its CCID-specific Reset Code, Option Type, and Feature Number ranges. These CCID-specific registries are independent: different CCIDs can allocate the same value (such as Feature Number 128) for different purposes. [RFC4340], Section 10.3, describes how DCCP decides which registry applies for a given CCID-specific Reset Code, Option Type, or Feature Number. In each case, CCID-specific registries may only register values 128-255; values 0-127 are registered here. For examples, see the following: http://www.iana.org/assignments/dccp-ccid2-parameters/dccp-ccid2-parameters.xhtml http://www.iana.org/assignments/dccp-ccid3-parameters/dccp-ccid3-parameters.xhtml http://www.iana.org/assignments/dccp-ccid4-parameters/dccp-ccid4-parameters.xhtml Licensing Terms