Protocol Registries Domains Protocols Numbers About Protocol Registries Protocol parameter registries represent the authoritative record of many of the codes and numbers contained in a variety of Internet protocols. We maintain these records in compliance with the associated technical standards and allocation policies, and we provide this service in coordination with the Internet Engineering Task Force (IETF). To view or download individual protocol registries, navigate to the individual registries through the index below. Registry data is available for bulk retrieval via Rsync (recommended) or FTP. To obtain a registration in an existing registry, or to modify existing registrations, consult the relevant application form. For information on creating new registries, please see RFC 8126 for guidance. × Protocol/Registry Defining Document/Comments Access Node Control Protocol (ANCP) ANCP Capability Types RFC 6320 Standards Action ANCP Command Codes RFC 6320 Standards Action ANCP Message Types RFC 6320 Standards Action ANCP Port Management Functions RFC 6320 Standards Action ANCP Result Codes RFC 6320 0x0-0xFFF: IETF Review. 0x1000-0xFFFFFF: Specification Required. ANCP Technology Types RFC 6320 Expert Review ANCP TLV Types RFC 6320 0x0000-0x1FFF: IETF Review. 0x2000-0xFFFF: Specification Required. Joint GSMP / ANCP Version Registry RFC 6320 Standards Action ACL TLS ACL (D)TLS Parameters RFC 9761 Expert Review Dan Wing Per Andersson ACL DTLS Version Codes RFC 9761 Expert Review Dan Wing Per Andersson ACL TLS Version Codes RFC 9761 Expert Review Dan Wing Per Andersson Ad Hoc On Demand Distance Vector (AODV) Parameters AODV Extension Types RFC 3561 Standards Action AODV Message Types (for messages sent to port 654) RFC 3561 Standards Action Address Family Numbers Address Family Numbers RFC 2453, RFC 2677, RFC 2858 1-16383: Standards Action. 16384-32767: First Come First Served. Address Resolution Protocol (ARP) Parameters Hardware Types RFC 826, RFC 5494 requests for values below 256: Expert Review. requests for more than one value: Expert Review. requests for one value greater than 255: First Come First Served. requests for one value, no value specified: First Come First Served. Carlos Pignataro Operation Codes RFC 826, RFC 5494 IETF Review or IESG Approval Protocol Type RFC 826, RFC 5494, RFC 5342 The Ethertype space is administered as described in [RFC5342]. APEX Parameters Applicable Exchange Core (APEX) Endpoint Applications RFC 3340 Expert Review Applicable Exchange Core (APEX) Options RFC 3340 Expert Review Applicable Exchange Core (APEX) Services RFC 3340 Expert Review Application Access Protocol (ACAP) Numbers ACAP Capabilities RFC 2244 Specification Required ACAP Response Codes RFC 2244 First Come First Served Dataset Classes RFC 2244 Standards Action or IESG-Approved Experimental RFC Vendor Subtrees RFC 2244, RFC 6075 First Come First Served Application Bridging for Federated Access Beyond Web (ABFAB) Parameters ABFAB URN Parameters RFC 7833 IETF Review or Expert Review Application-Layer Traffic Optimization (ALTO) Protocol ALTO Address Types RFC 7285 IETF Review ALTO Cost Metrics RFC 7285 IETF Review ALTO Cost Modes RFC 9274 IETF Review ALTO Cost Source Types RFC 9439 IETF Review ALTO Endpoint Property Types RFC 7285 IETF Review ALTO Entity Domain Types RFC 9240 IETF Review ALTO Entity Property Types RFC 9240 IETF Review ALTO Error Codes RFC 7285 IETF Review Authenticated Encryption with Associated Data (AEAD) Parameters AEAD Algorithms RFC 5116 1-32767: Specification Required. 32768-65535: Private Use. David McGrew Bjoern Tackmann Stanislav Smyshlyaev Authentication and Authorization for Constrained Environments (ACE) ACE Authorization Server Request Creation Hints RFC 9200 less than -65536: Private Use. -65536 to -257: Specification Required. -256 to 255: Standards Action. 256 to 65535: Specification Required. greater than 65535: Expert Review. Göran Selander ACE Groupcomm Errors RFC 9594 less than -65536: Private Use. -65536 to -257: Specification Required. -256 to 255: Standards Action With Expert Review. 256 to 65535: Specification Required. greater than 65535: Expert Review. Francesca Palombini Marco Tiloca Rikard Höglund ACE Groupcomm Key Types RFC 9594 less than -65536: Private Use. -65536 to -257: Specification Required. -256 to 255: Standards Action With Expert Review. 256 to 65535: Specification Required. greater than 65535: Expert Review. Strings of length 1: Standards Action With Expert Review. Strings of length 2: Specification Required. Strings of length greater than 2: Expert Review. Francesca Palombini Marco Tiloca Rikard Höglund ACE Groupcomm Parameters RFC 9594 less than -65536: Private Use. -65536 to -257: Specification Required. -256 to 255: Standards Action With Expert Review. 256 to 65535: Specification Required. greater than 65535: Expert Review. Strings of length 1: Standards Action With Expert Review. Strings of length 2: Specification Required. Strings of length greater than 2: Expert Review. Francesca Palombini Marco Tiloca Rikard Höglund ACE Groupcomm Policies RFC 9594 less than -65536: Private Use. -65536 to -257: Specification Required. -256 to 255: Standards Action With Expert Review. 256 to 65535: Specification Required. greater than 65535: Expert Review. Strings of length 1: Standards Action With Expert Review. Strings of length 2: Specification Required. Strings of length greater than 2: Expert Review. Francesca Palombini Marco Tiloca Rikard Höglund ACE Groupcomm Profiles RFC 9594 less than -65536: Private Use. -65536 to -257: Specification Required. -256 to 255: Standards Action With Expert Review. 256 to 65535: Specification Required. greater than 65535: Expert Review. Francesca Palombini Marco Tiloca Rikard Höglund ACE Groupcomm Rekeying Schemes RFC 9594 less than -65536: Private Use. -65536 to -257: Specification Required. -256 to 255: Standards Action With Expert Review. 256 to 65535: Specification Required. greater than 65535: Expert Review. Francesca Palombini Marco Tiloca Rikard Höglund ACE Profiles RFC 9200 less than -65536: Private Use. -65536 to -257: Specification Required. -256 to 255: Standards Action. 256 to 65535: Specification Required. greater than 65535: Expert Review. Göran Selander ACE Token Revocation List Errors RFC 9770 less than -65536: Private Use. -65536 to -257: Specification Required. -256 to 255: Standards Action With Expert Review. 256 to 65535: Specification Required. greater than 65535: Expert Review. Marco Tiloca Marco Rasori ACE Token Revocation List Parameters RFC 9770 less than -65536: Private Use. -65536 to -257: Specification Required. -256 to 255: Standards Action With Expert Review. 256 to 65535: Specification Required. greater than 65535: Expert Review. Marco Tiloca Marco Rasori Group OSCORE Admin Permissions draft-ietf-ace-oscore-gm-admin-17 0-65535: Expert Review. greater than 65535: Private Use. Group OSCORE Roles draft-ietf-ace-key-groupcomm-oscore-21 0-65535: Expert Review. greater than 65535: Private Use. OAuth Access Token Type CBOR Mappings RFC 9200 less than -65536: Private Use. -65536 or greater: Expert Review. Göran Selander OAuth Error Code CBOR Mappings RFC 9200 less than -65536: Private Use. -65536 or greater: Expert Review. Göran Selander OAuth Grant Type CBOR Mappings RFC 9200 less than -65536: Private Use. -65536 or greater: Expert Review. Göran Selander OAuth Parameters CBOR Mappings RFC 9200 less than -65536: Private Use. -65536 or greater: Expert Review. Göran Selander OAuth Token Introspection Response CBOR Mappings RFC 9200 less than -65536: Private Use. -65536 or greater: Expert Review. Göran Selander OSCORE Security Context Parameters RFC 9203 less than -65536: Private Use. -65536 to -257: Specification Required. -256 to 255: Standards Action With Expert Review. 256 to 65535: Specification Required. greater than 65535: Expert Review. Strings of length 1: Standards Action With Expert Review. Strings of length 2: Specification Required. Strings of length greater than 2: Expert Review. Göran Selander Sequence Number Synchronization Methods RFC 9594 less than -65536: Private Use. -65536 to -257: Specification Required. -256 to 255: Standards Action With Expert Review. 256 to 65535: Specification Required. greater than 65535: Expert Review. Strings of length 1: Standards Action With Expert Review. Strings of length 2: Specification Required. Strings of length greater than 2: Expert Review. Francesca Palombini Marco Tiloca Rikard Höglund Authentication and Key Agreement (AKA) AKA-Version Namespace RFC 3310 Expert Review Vesa Torvinen (primary) Jari Arkko (secondary) Authentication Method Reference Values Authentication Method Reference Values RFC 8176 Expert Review John Bradley Mike Jones Authentication Option Name Spaces Algorithm Name Space Values RFC 3118 IETF Review Protocol Name Space Values RFC 3118 IETF Review RDM Name Space Values RFC 3118 IETF Review Authentication, Authorization, and Accounting (AAA) Parameters Application IDs RFC 6733, RFC 6942 0-16777215: Specification Required. 16777216-4294967294: First Come First Served. AVP Codes RFC 6733 block allocation (release of more than three AVPs at a time for a given purpose): IETF Review. other allocation: Specification Required. Lionel Morand (primary) Jouni Korhonen (secondary) AVP Flags Value RFC 6733 Standards Action AVP Specific Values RFC 6733 IETF Review (unless otherwise specified) Command Codes RFC 6733, RFC 5719 0-255: Reserved for RADIUS backward compatibility. 256-8388607: IETF Review. 8388608-16777213: First Come First Served with specification. Command Flags RFC 6733 Standards Action Mobility Capability Registry RFC 5447 Specification Required Jouni Korhonen QoS Profiles RFC 5624 0-511: Standards Action. 512-32767: Specification Required. 32768-4294967295: Reserved. Author Domain Signing Practices (ADSP) Parameters ADSP Outbound Signing Practices RFC 5617 Registry closed ADSP Specification Tags RFC 5617 Registry closed Automated Certificate Management Environment (ACME) Protocol ACME Account Object Fields RFC 8555 Specification Required Richard Barnes Aaron Gable ACME Authority Token Challenge Types RFC 9447 Specification Required Mary Barnes Aaron Gable ACME Authorization Object Fields RFC 8555 Specification Required Richard Barnes Aaron Gable ACME Directory Metadata Auto-Renewal Fields RFC 8739 Specification Required Yaron Sheffer Diego R. Lopez Thomas Fossati Aaron Gable ACME Directory Metadata Fields RFC 8555 Specification Required Richard Barnes Aaron Gable ACME Error Types RFC 8555 Specification Required Richard Barnes Aaron Gable ACME Identifier Types RFC 8555 Specification Required Richard Barnes Aaron Gable ACME Order Auto-Renewal Fields RFC 8739 Specification Required Yaron Sheffer Diego R. Lopez Thomas Fossati Aaron Gable ACME Order Object Fields RFC 8555 Specification Required Richard Barnes Aaron Gable ACME RenewalInfo Object Fields RFC 9773 Specification Required Richard Barnes Aaron Gable ACME Resource Types RFC 8555 Specification Required Richard Barnes Aaron Gable ACME Validation Methods RFC 8555 Specification Required Richard Barnes Aaron Gable STAR Delegation CSR Template Extensions RFC 9115 Specification Required Yaron Sheffer Diego R. Lopez Thomas Fossati Aaron Gable Automatic Responses to Electronic Mail Parameters Auto-Submitted Header Field Keywords RFC 5436 Specification Required Auto-Submitted header field optional parameters RFC 3834 IETF Review Autonomic Control Plane (ACP) ACP Address Type RFC 8994 Standards Action Autonomous System (AS) Numbers 16-bit Autonomous System Numbers RFC 1930, RFC 5398, RFC 6996, RFC 7249 RIR request to the IANA or IETF Review. Allocated following the Global Policy published at http://www.icann.org/en/resources/policy/global-addressing. 32-bit Autonomous System Numbers RFC 1930, RFC 5398, RFC 6793, RFC 6996, RFC 7249 RIR request to the IANA or IETF Review. Allocated following the Global Policy published at http://www.ica…