RFC Index — Core Internet Standards

A reference mirror of 299 of the most-cited IETF Request for Comments documents — the protocols behind the web, email, DNS, routing and cryptography. Maintained by Ruslan Averin at RFC Capital Research.

RFC 114 — File Transfer Protocol
RFC 768 — User Datagram Protocol
RFC 791 — Internet Protocol
RFC 792 — Internet Control Message Protocol
RFC 793 — Transmission Control Protocol
RFC 822 — STANDARD FOR THE FORMAT OF ARPA INTERNET TEXT MESSAGES
RFC 826 — An Ethernet Address Resolution Protocol: Or Converting Network Protocol Addresses to 48.bit Ethernet Address for Transmission on Ethernet Hardware
RFC 854 — Telnet Protocol Specification
RFC 855 — Telnet Option Specifications
RFC 862 — Echo Protocol
RFC 863 — Discard Protocol
RFC 864 — Character Generator Protocol
RFC 865 — Quote of the Day Protocol
RFC 867 — Daytime Protocol
RFC 868 — Time Protocol
RFC 958 — Network Time Protocol (NTP)
RFC 959 — File Transfer Protocol
RFC 977 — Network News Transfer Protocol
RFC 1034 — Domain names - concepts and facilities
RFC 1035 — Domain names - implementation and specification
RFC 1058 — Routing Information Protocol
RFC 1112 — Host extensions for IP multicasting
RFC 1122 — Requirements for Internet Hosts - Communication Layers
RFC 1123 — Requirements for Internet Hosts - Application and Support
RFC 1149 — Standard for the transmission of IP datagrams on avian carriers
RFC 1155 — Structure and identification of management information for TCP/IP-based internets
RFC 1157 — Simple Network Management Protocol (SNMP)
RFC 1180 — TCP/IP tutorial
RFC 1195 — Use of OSI IS-IS for routing in TCP/IP and dual environments
RFC 1213 — Management Information Base for Network Management of TCP/IP-based internets: MIB-II
RFC 1288 — The Finger User Information Protocol
RFC 1305 — Network Time Protocol (Version 3) Specification, Implementation and Analysis
RFC 1321 — The MD5 Message-Digest Algorithm
RFC 1350 — The TFTP Protocol (Revision 2)
RFC 1413 — Identification Protocol
RFC 1459 — Internet Relay Chat Protocol
RFC 1519 — Classless Inter-Domain Routing (CIDR): an Address Assignment and Aggregation Strategy
RFC 1541 — Dynamic Host Configuration Protocol
RFC 1661 — The Point-to-Point Protocol (PPP)
RFC 1738 — Uniform Resource Locators (URL)
RFC 1812 — Requirements for IP Version 4 Routers
RFC 1918 — Address Allocation for Private Internets
RFC 1925 — The Twelve Networking Truths
RFC 1939 — Post Office Protocol - Version 3
RFC 1945 — Hypertext Transfer Protocol -- HTTP/1.0
RFC 1950 — ZLIB Compressed Data Format Specification version 3.3
RFC 1951 — DEFLATE Compressed Data Format Specification version 1.3
RFC 1952 — GZIP file format specification version 4.3
RFC 1995 — Incremental Zone Transfer in DNS
RFC 1996 — A Mechanism for Prompt Notification of Zone Changes (DNS NOTIFY)
RFC 2018 — TCP Selective Acknowledgment Options
RFC 2030 — Simple Network Time Protocol (SNTP) Version 4 for IPv4, IPv6 and OSI
RFC 2045 — Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies
RFC 2046 — Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types
RFC 2047 — MIME (Multipurpose Internet Mail Extensions) Part Three: Message Header Extensions for Non-ASCII Text
RFC 2048 — Multipurpose Internet Mail Extensions (MIME) Part Four: Registration Procedures
RFC 2049 — Multipurpose Internet Mail Extensions (MIME) Part Five: Conformance Criteria and Examples
RFC 2083 — PNG (Portable Network Graphics) Specification Version 1.0
RFC 2104 — HMAC: Keyed-Hashing for Message Authentication
RFC 2109 — HTTP State Management Mechanism
RFC 2119 — Key words for use in RFCs to Indicate Requirement Levels
RFC 2131 — Dynamic Host Configuration Protocol
RFC 2132 — DHCP Options and BOOTP Vendor Extensions
RFC 2136 — Dynamic Updates in the Domain Name System (DNS UPDATE)
RFC 2183 — Communicating Presentation Information in Internet Messages: The Content-Disposition Header Field
RFC 2228 — FTP Security Extensions
RFC 2236 — Internet Group Management Protocol, Version 2
RFC 2246 — The TLS Protocol Version 1.0
RFC 2308 — Negative Caching of DNS Queries (DNS NCACHE)
RFC 2315 — PKCS #7: Cryptographic Message Syntax Version 1.5
RFC 2324 — Hyper Text Coffee Pot Control Protocol (HTCPCP/1.0)
RFC 2328 — OSPF Version 2
RFC 2338 — Virtual Router Redundancy Protocol
RFC 2347 — TFTP Option Extension
RFC 2368 — The mailto URL scheme
RFC 2392 — Content-ID and Message-ID Uniform Resource Locators
RFC 2396 — Uniform Resource Identifiers (URI): Generic Syntax
RFC 2409 — The Internet Key Exchange (IKE)
RFC 2426 — vCard MIME Directory Profile
RFC 2428 — FTP Extensions for IPv6 and NATs
RFC 2460 — Internet Protocol, Version 6 (IPv6) Specification
RFC 2475 — An Architecture for Differentiated Services
RFC 2516 — A Method for Transmitting PPP Over Ethernet (PPPoE)
RFC 2518 — HTTP Extensions for Distributed Authoring -- WEBDAV
RFC 2549 — IP over Avian Carriers with Quality of Service
RFC 2595 — Using TLS with IMAP, POP3 and ACAP
RFC 2606 — Reserved Top Level DNS Names
RFC 2616 — Hypertext Transfer Protocol -- HTTP/1.1
RFC 2637 — Point-to-Point Tunneling Protocol (PPTP)
RFC 2661 — Layer Two Tunneling Protocol "L2TP"
RFC 2671 — Extension Mechanisms for DNS (EDNS0)
RFC 2782 — A DNS RR for specifying the location of services (DNS SRV)
RFC 2784 — Generic Routing Encapsulation (GRE)
RFC 2795 — The Infinite Monkey Protocol Suite (IMPS)
RFC 2812 — Internet Relay Chat: Client Protocol
RFC 2818 — HTTP Over TLS
RFC 2819 — Remote Network Monitoring Management Information Base
RFC 2822 — Internet Message Format
RFC 2833 — RTP Payload for DTMF Digits, Telephony Tones and Telephony Signals
RFC 2849 — The LDAP Data Interchange Format (LDIF) - Technical Specification
RFC 2865 — Remote Authentication Dial In User Service (RADIUS)
RFC 2866 — RADIUS Accounting
RFC 2890 — Key and Sequence Number Extensions to GRE
RFC 2965 — HTTP State Management Mechanism
RFC 2986 — PKCS #10: Certification Request Syntax Specification Version 1.7
RFC 3022 — Traditional IP Network Address Translator (Traditional NAT)
RFC 3031 — Multiprotocol Label Switching Architecture
RFC 3032 — MPLS Label Stack Encoding
RFC 3092 — Etymology of "Foo"
RFC 3161 — Internet X.509 Public Key Infrastructure Time-Stamp Protocol (TSP)
RFC 3164 — The BSD Syslog Protocol
RFC 3168 — The Addition of Explicit Congestion Notification (ECN) to IP
RFC 3174 — US Secure Hash Algorithm 1 (SHA1)
RFC 3207 — SMTP Service Extension for Secure SMTP over Transport Layer Security
RFC 3209 — RSVP-TE: Extensions to RSVP for LSP Tunnels
RFC 3261 — SIP: Session Initiation Protocol
RFC 3262 — Reliability of Provisional Responses in Session Initiation Protocol (SIP)
RFC 3263 — Session Initiation Protocol (SIP): Locating SIP Servers
RFC 3264 — An Offer/Answer Model with Session Description Protocol (SDP)
RFC 3315 — Dynamic Host Configuration Protocol for IPv6 (DHCPv6)
RFC 3325 — Private Extensions to the Session Initiation Protocol (SIP) for Asserted Identity within Trusted Networks
RFC 3339 — Date and Time on the Internet: Timestamps
RFC 3376 — Internet Group Management Protocol, Version 3
RFC 3394 — Advanced Encryption Standard (AES) Key Wrap Algorithm
RFC 3411 — An Architecture for Describing Simple Network Management Protocol (SNMP) Management Frameworks
RFC 3414 — User-based Security Model (USM) for version 3 of the Simple Network Management Protocol (SNMPv3)
RFC 3461 — Simple Mail Transfer Protocol (SMTP) Service Extension for Delivery Status Notifications (DSNs)
RFC 3489 — STUN - Simple Traversal of User Datagram Protocol (UDP) Through Network Address Translators (NATs)
RFC 3492 — Punycode: A Bootstring encoding of Unicode for Internationalized Domain Names in Applications (IDNA)
RFC 3501 — INTERNET MESSAGE ACCESS PROTOCOL - VERSION 4rev1
RFC 3514 — The Security Flag in the IPv4 Header
RFC 3515 — The Session Initiation Protocol (SIP) Refer Method
RFC 3550 — RTP: A Transport Protocol for Real-Time Applications
RFC 3596 — DNS Extensions to Support IP Version 6
RFC 3659 — Extensions to FTP
RFC 3711 — The Secure Real-time Transport Protocol (SRTP)
RFC 3798 — Message Disposition Notification
RFC 3834 — Recommendations for Automatic Responses to Electronic Mail
RFC 3891 — The Session Initiation Protocol (SIP) "Replaces" Header
RFC 3892 — The Session Initiation Protocol (SIP) Referred-By Mechanism
RFC 3931 — Layer Two Tunneling Protocol - Version 3 (L2TPv3)
RFC 3948 — UDP Encapsulation of IPsec ESP Packets
RFC 3956 — Embedding the Rendezvous Point (RP) Address in an IPv6 Multicast Address
RFC 3966 — The tel URI for Telephone Numbers
RFC 3986 — Uniform Resource Identifier (URI): Generic Syntax
RFC 3987 — Internationalized Resource Identifiers (IRIs)
RFC 4028 — Session Timers in the Session Initiation Protocol (SIP)
RFC 4033 — DNS Security Introduction and Requirements
RFC 4034 — Resource Records for the DNS Security Extensions
RFC 4035 — Protocol Modifications for the DNS Security Extensions
RFC 4122 — A Universally Unique IDentifier (UUID) URN Namespace
RFC 4180 — Common Format and MIME Type for Comma-Separated Values (CSV) Files
RFC 4193 — Unique Local IPv6 Unicast Addresses
RFC 4251 — The Secure Shell (SSH) Protocol Architecture
RFC 4252 — The Secure Shell (SSH) Authentication Protocol
RFC 4253 — The Secure Shell (SSH) Transport Layer Protocol
RFC 4254 — The Secure Shell (SSH) Connection Protocol
RFC 4271 — A Border Gateway Protocol 4 (BGP-4)
RFC 4287 — The Atom Syndication Format
RFC 4291 — IP Version 6 Addressing Architecture
RFC 4301 — Security Architecture for the Internet Protocol
RFC 4302 — IP Authentication Header
RFC 4303 — IP Encapsulating Security Payload (ESP)
RFC 4330 — Simple Network Time Protocol (SNTP) Version 4 for IPv4, IPv6 and OSI
RFC 4343 — Domain Name System (DNS) Case Insensitivity Clarification
RFC 4346 — The Transport Layer Security (TLS) Protocol Version 1.1
RFC 4360 — BGP Extended Communities Attribute
RFC 4364 — BGP/MPLS IP Virtual Private Networks (VPNs)
RFC 4443 — Internet Control Message Protocol (ICMPv6) for the Internet Protocol Version 6 (IPv6) Specification
RFC 4456 — BGP Route Reflection: An Alternative to Full Mesh Internal BGP (IBGP)
RFC 4510 — Lightweight Directory Access Protocol (LDAP): Technical Specification Road Map
RFC 4511 — Lightweight Directory Access Protocol (LDAP): The Protocol
RFC 4512 — Lightweight Directory Access Protocol (LDAP): Directory Information Models
RFC 4513 — Lightweight Directory Access Protocol (LDAP): Authentication Methods and Security Mechanisms
RFC 4514 — Lightweight Directory Access Protocol (LDAP): String Representation of Distinguished Names
RFC 4515 — Lightweight Directory Access Protocol (LDAP): String Representation of Search Filters
RFC 4516 — Lightweight Directory Access Protocol (LDAP): Uniform Resource Locator
RFC 4566 — SDP: Session Description Protocol
RFC 4601 — Protocol Independent Multicast - Sparse Mode (PIM-SM): Protocol Specification (Revised)
RFC 4627 — The application/json Media Type for JavaScript Object Notation (JSON)
RFC 4632 — Classless Inter-domain Routing (CIDR): The Internet Address Assignment and Aggregation Plan
RFC 4647 — Matching of Language Tags
RFC 4648 — The Base16, Base32, and Base64 Data Encodings
RFC 4733 — RTP Payload for DTMF Digits, Telephony Tones, and Telephony Signals
RFC 4760 — Multiprotocol Extensions for BGP-4
RFC 4791 — Calendaring Extensions to WebDAV (CalDAV)
RFC 4861 — Neighbor Discovery for IP version 6 (IPv6)
RFC 4862 — IPv6 Stateless Address Autoconfiguration
RFC 4918 — HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV)
RFC 4941 — Privacy Extensions for Stateless Address Autoconfiguration in IPv6
RFC 4954 — SMTP Service Extension for Authentication
RFC 5023 — The Atom Publishing Protocol
RFC 5036 — LDP Specification
RFC 5065 — Autonomous System Confederations for BGP
RFC 5104 — Codec Control Messages in the RTP Audio-Visual Profile with Feedback (AVPF)
RFC 5228 — Sieve: An Email Filtering Language
RFC 5234 — Augmented BNF for Syntax Specifications: ABNF
RFC 5245 — Interactive Connectivity Establishment (ICE): A Protocol for Network Address Translator (NAT) Traversal for Offer/Answer Protocols
RFC 5246 — The Transport Layer Security (TLS) Protocol Version 1.2
RFC 5280 — Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile
RFC 5288 — AES Galois Counter Mode (GCM) Cipher Suites for TLS
RFC 5308 — Routing IPv6 with IS-IS
RFC 5321 — Simple Mail Transfer Protocol
RFC 5322 — Internet Message Format
RFC 5323 — Web Distributed Authoring and Versioning (WebDAV) SEARCH
RFC 5340 — OSPF for IPv6
RFC 5389 — Session Traversal Utilities for NAT (STUN)
RFC 5424 — The Syslog Protocol
RFC 5425 — Transport Layer Security (TLS) Transport Mapping for Syslog
RFC 5545 — Internet Calendaring and Scheduling Core Object Specification (iCalendar)
RFC 5646 — Tags for Identifying Languages
RFC 5652 — Cryptographic Message Syntax (CMS)
RFC 5766 — Traversal Using Relays around NAT (TURN): Relay Extensions to Session Traversal Utilities for NAT (STUN)
RFC 5789 — PATCH Method for HTTP
RFC 5869 — HMAC-based Extract-and-Expand Key Derivation Function (HKDF)
RFC 5890 — Internationalized Domain Names for Applications (IDNA): Definitions and Document Framework
RFC 5905 — Network Time Protocol Version 4: Protocol and Algorithms Specification
RFC 5952 — A Recommendation for IPv6 Address Text Representation
RFC 5958 — Asymmetric Key Packages
RFC 5966 — DNS Transport over TCP - Implementation Requirements
RFC 5988 — Web Linking
RFC 5996 — Internet Key Exchange Protocol Version 2 (IKEv2)
RFC 6052 — IPv6 Addressing of IPv4/IPv6 Translators
RFC 6068 — The 'mailto' URI Scheme
RFC 6101 — The Secure Sockets Layer (SSL) Protocol Version 3.0
RFC 6120 — Extensible Messaging and Presence Protocol (XMPP): Core
RFC 6121 — Extensible Messaging and Presence Protocol (XMPP): Instant Messaging and Presence
RFC 6145 — IP/ICMP Translation Algorithm
RFC 6146 — Stateful NAT64: Network Address and Protocol Translation from IPv6 Clients to IPv4 Servers
RFC 6234 — US Secure Hash Algorithms (SHA and SHA-based HMAC and HKDF)
RFC 6265 — HTTP State Management Mechanism
RFC 6350 — vCard Format Specification
RFC 6352 — CardDAV: vCard Extensions to Web Distributed Authoring and Versioning (WebDAV)
RFC 6376 — DomainKeys Identified Mail (DKIM) Signatures
RFC 6454 — The Web Origin Concept
RFC 6455 — The WebSocket Protocol
RFC 6531 — SMTP Extension for Internationalized Email
RFC 6585 — Additional HTTP Status Codes
RFC 6598 — IANA-Reserved IPv4 Prefix for Shared Address Space
RFC 6733 — Diameter Base Protocol
RFC 6749 — The OAuth 2.0 Authorization Framework
RFC 6750 — The OAuth 2.0 Authorization Framework: Bearer Token Usage
RFC 6762 — Multicast DNS
RFC 6763 — DNS-Based Service Discovery
RFC 6797 — HTTP Strict Transport Security (HSTS)
RFC 6890 — Special-Purpose IP Address Registries
RFC 6891 — Extension Mechanisms for DNS (EDNS(0))
RFC 6901 — JavaScript Object Notation (JSON) Pointer
RFC 6902 — JavaScript Object Notation (JSON) Patch
RFC 6960 — X.509 Internet Public Key Infrastructure Online Certificate Status Protocol - OCSP
RFC 6979 — Deterministic Usage of the Digital Signature Algorithm (DSA) and Elliptic Curve Digital Signature Algorithm (ECDSA)
RFC 7034 — HTTP Header Field X-Frame-Options
RFC 7049 — Concise Binary Object Representation (CBOR)
RFC 7168 — The Hyper Text Coffee Pot Control Protocol for Tea Efflux Appliances (HTCPCP-TEA)
RFC 7208 — Sender Policy Framework (SPF) for Authorizing Use of Domains in Email, Version 1
RFC 7230 — Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing
RFC 7231 — Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content
RFC 7232 — Hypertext Transfer Protocol (HTTP/1.1): Conditional Requests
RFC 7233 — Hypertext Transfer Protocol (HTTP/1.1): Range Requests
RFC 7234 — Hypertext Transfer Protocol (HTTP/1.1): Caching
RFC 7235 — Hypertext Transfer Protocol (HTTP/1.1): Authentication
RFC 7296 — Internet Key Exchange Protocol Version 2 (IKEv2)
RFC 7301 — Transport Layer Security (TLS) Application-Layer Protocol Negotiation Extension
RFC 7323 — TCP Extensions for High Performance
RFC 7348 — Virtual eXtensible Local Area Network (VXLAN): A Framework for Overlaying Virtualized Layer 2 Networks over Layer 3 Networks
RFC 7396 — JSON Merge Patch
RFC 7432 — BGP MPLS-Based Ethernet VPN
RFC 7469 — Public Key Pinning Extension for HTTP
RFC 7489 — Domain-based Message Authentication, Reporting, and Conformance (DMARC)
RFC 7515 — JSON Web Signature (JWS)
RFC 7516 — JSON Web Encryption (JWE)
RFC 7517 — JSON Web Key (JWK)
RFC 7518 — JSON Web Algorithms (JWA)
RFC 7519 — JSON Web Token (JWT)
RFC 7538 — The Hypertext Transfer Protocol Status Code 308 (Permanent Redirect)
RFC 7539 — ChaCha20 and Poly1305 for IETF Protocols
RFC 7540 — Hypertext Transfer Protocol Version 2 (HTTP/2)
RFC 7541 — HPACK: Header Compression for HTTP/2
RFC 7616 — HTTP Digest Access Authentication
RFC 7617 — The 'Basic' HTTP Authentication Scheme
RFC 7692 — Compression Extensions for WebSocket
RFC 7742 — WebRTC Video Processing and Codec Requirements
RFC 7748 — Elliptic Curves for Security
RFC 7807 — Problem Details for HTTP APIs
RFC 7858 — Specification for DNS over Transport Layer Security (TLS)
RFC 7874 — WebRTC Audio Codec and Processing Requirements
RFC 7983 — Multiplexing Scheme Updates for Secure Real-time Transport Protocol (SRTP) Extension for Datagram Transport Layer Security (DTLS)
RFC 8017 — PKCS #1: RSA Cryptography Specifications Version 2.2
RFC 8032 — Edwards-Curve Digital Signature Algorithm (EdDSA)
RFC 8174 — Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words
RFC 8200 — Internet Protocol, Version 6 (IPv6) Specification
RFC 8259 — The JavaScript Object Notation (JSON) Data Interchange Format
RFC 8288 — Web Linking
RFC 8439 — ChaCha20 and Poly1305 for IETF Protocols
RFC 8446 — The Transport Layer Security (TLS) Protocol Version 1.3
RFC 8484 — DNS Queries over HTTPS (DoH)
RFC 8551 — Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 4.0 Message Specification
RFC 8825 — Overview: Real-Time Protocols for Browser-Based Applications
RFC 9000 — QUIC: A UDP-Based Multiplexed and Secure Transport