List of RFCs


This is a partial list of RFCs. A Request for Comments is a publication in a series from the principal technical development and standards-setting bodies for the Internet, most prominently the Internet Engineering Task Force.
While there are over 9,901 RFCs as of November 2025, this list consists of RFCs that have related articles. A complete list is available from the IETF website.

Numerical list

#TitleDate publishedRelated articleMade obsolete byNotes
ASCII format for Network InterchangeOctober 16, 1969ASCII
Message Data Types31 March 1970
User Datagram ProtocolAugust 28, 1980UDP
THE TFTP PROTOCOL June 1981TFTPRFC 1350
Internet ProtocolSeptember 1981IPv4
INTERNET CONTROL MESSAGE PROTOCOLSeptember 1981ICMP
TRANSMISSION CONTROL PROTOCOLSeptember 1981TCPRFC 9293
An Ethernet Address Resolution ProtocolNovember 1982ARP
TELNET PROTOCOL SPECIFICATIONMay 1983Telnet
TELNET OPTION SPECIFICATIONSMay 1983Telnet
Echo ProtocolMay 1983Echo
Discard ProtocolMay 1983DISCARD
Character Generator ProtocolMay 1983CHARGEN
Time ProtocolMay 1983TIME
A Reverse Address Resolution ProtocolJune 1984RARP
POST OFFICE PROTOCOL - VERSION 2February 1985POP v 2
BOOTSTRAP PROTOCOL September 1985BOOTP
FILE TRANSFER PROTOCOL October 1985FTP
DOMAIN NAMES - CONCEPTS AND FACILITIESNovember 1987DNS
DOMAIN NAMES - IMPLEMENTATION AND SPECIFICATIONNovember 1987DNS
Standard for Interchange of USENET MessagesDecember 1987Usenet
A Non-Standard for Transmission of IP Datagrams Over Serial Lines: SLIPJune 1988Serial Line [Internet Protocol|SLIP]
Routing Information ProtocolJune 1988RIP v 1
Network Time Protocol specification and implementationJuly 1988NTP v 1
Ethics and the InternetJanuary 1989Internet Ethics
The Hitchhikers Guide to the InternetSeptember 1989The Hitchhikers Guide to the Internet
Network Time Protocol specification and implementationSeptember 1989NTP v 2
A Standard for the Transmission of IP Datagrams on Avian CarriersApril 1, 1990IP over Avian Carriers
A Simple Network Management Protocol May 1990SNMP v1
INTERACTIVE MAIL ACCESS PROTOCOL - VERSION 2August 1990IMAP v 2
Path MTU DiscoveryNovember 1990PMTUDObsoletes RFC 1063
Network Time Protocol Specification, Implementation and AnalysisMarch 1992NTP v 3RFC 5905Obsoletes RFC 1119, RFC 1059, RFC 958
The MD5 Message-Digest AlgorithmApril 1992MD5
THE TFTP PROTOCOL July 1992TFTPObsoletes RFC 783
The Internet Gopher ProtocolMarch 1993Gopher
Introduction to version 2 of the Internet-standard Network Management FrameworkApril 1993SNMP v 2
Internet Relay Chat ProtocolMay 1993IRC
INTERNET MESSAGE ACCESS PROTOCOL - VERSION 4December 1994IMAP v 4
Lightweight Directory Access ProtocolMarch 1995LDAP
Netiquette GuidelinesOctober 1995Netiquette
Address Allocation for Private InternetsFebruary 1996Private network
SOCKS Protocol Version 5March 1996SOCKS5
Post Office Protocol - Version 3May 1996POP v 3
Hypertext Transfer Protocol—HTTP/1.0May 1996HTTP v 1.0
Defending Against Sequence Number AttacksMay 1996IP spoofing
ZLIB Compressed Data Format Specification version 3.3May 1996Zlib v 3.3
DEFLATE Compressed Data Format Specification version 1.3May 1996DEFLATE v 1.3
GZIP file format specification version 4.3May 1996Gzip v 4.3
The Kerberos Version 5 GSS-API MechanismJune 1996Kerberos; GSSAPI
RIPng for IPv6January 1997RIP v ng
Key words for use in RFCs to Indicate Requirement LevelsMarch 1997Request for CommentsUpdated by RFC 8174
Dynamic Host Configuration ProtocolMarch 1997DHCP
IMAP4 IDLE commandJune 1997IMAP IDLE
IMAP/POP AUTHorize Extension for Simple Challenge/ResponseSeptember 1997CRAM-MD5
FTP Security ExtensionsOctober 1997FTP
Key Exchange Delegation Record for the DNSNovember 1997Secure DNS
The TLS Protocol Version 1.0January 1999TLS 1.0
Lightweight Directory Access Protocol December 1997LDAP v 3
Lightweight Directory Access Protocol : Attribute Syntax DefinitionsDecember 1997LDAP v 3
Lightweight Directory Access Protocol : UTF-8 String Representation of Distinguished NamesDecember 1997LDAP v 3
The String Representation of LDAP Search FiltersDecember 1997LDAP v 3
The LDAP URL FormatDecember 1997LDAP v 3
A Summary of the X.500 User Schema for use with LDAPv3December 1997LDAP v 3
Real Time Streaming Protocol April 1998RTSP
SDP: Session Description ProtocolApril 1998SDP
OSPF Version 2April 1998OSPF
Mapping of Airline Reservation, Ticketing, and Messaging Traffic over IPMay 1998MATIP
Protocol Independent Multicast-Sparse Mode June 1998PIM
The "data" URL schemeAugust 1998Data: URI scheme
Internet IP Security Domain of Interpretation for ISAKMP.November 1998IKE
Internet Security Association and Key Management Protocol November 1998IKE
The Internet Key Exchange November 1998IKE
Multiprotocol Interconnect over Frame RelaySeptember 1998Frame Relay1294, 1490
RIP Version 2November 1998RIP v 2
Internet Protocol, Version 6 SpecificationDecember 1998IPv6RFC 8200
IP over Avian Carriers with Quality of ServiceApril 1, 1999IP over Avian Carriers
30 Years of RFCsApril 7, 1999Retraces the history of RFCs
Introduction to Version 3 of the Internet-standard Network Management FrameworkApril 1999SNMP v3
Using TLS with IMAP, POP3 and ACAPJune 1999STARTTLS for IMAP, POP3 and ACAP
Reserved Top Level DNS NamesJune 1999Fictitious domain nameexample.com,.test,...
OSPF for IPv6December 1999OSPF
Generic Security Service Application Program Interface Version 2, Update 1January 2000GSSAPI v 2
Generic Security Service API Version 2 : C-bindingsJanuary 2000GSSAPI v 2
Internet Open Trading Protocol - IOTP Version 1.0April 2000Internet Open Trading Protocol
Digital Signatures for the v1.0 Internet Open Trading Protocol April 2000Internet Open Trading Protocol
Internet Relay Chat: ArchitectureApril 2000IRC
Internet Relay Chat: Channel ManagementApril 2000IRC
Internet Relay Chat: Client ProtocolApril 2000IRC
Internet Relay Chat: Server ProtocolApril 2000IRC
Generic Security Service API Version 2 : Java BindingsJune 2000GSSAPI v 2
Remote Authentication Dial In User Service June 2000RADIUS
RADIUS AccountingJune 2000RADIUS
Internet Open Trading Protocol HTTP SupplementSeptember 2000Internet Open Trading Protocol
Session Announcement ProtocolOctober 2000SAP
Internet Open Trading Protocol, Version 1, ErrataMarch 2003Internet Open Trading Protocol
Traditional IP Network Address Translator January 2001NAT
Multiprotocol Label Switching ArchitectureJanuary 2001MPLS
IPv6 Tunnel BrokerJanuary 2001Tunnel Broker
Connection of IPv6 Domains via IPv4 CloudsFebruary 20016to4
The Blocks Extensible Exchange Protocol CoreMarch 2001BEEP
RADIUS and IPv6August 2001RADIUS
SMTP Service Extension for Secure SMTP over Transport Layer SecurityFebruary 2002STARTTLS for SMTP
SIP: Session Initiation ProtocolJune 2002SIP
The VCDIFF Generic Differencing and Compression Data FormatJune 2002VCDIFF
An Introduction to the Stream Control Transmission Protocol May 2002SCTP
Dynamic Host Configuration Protocol for IPv6 July 2003DHCP
Date and Time on the Internet: TimestampsJuly 2002Timestamp
Internet Group Management Protocol, Version 3October 2002IGMP v 3
Dynamic Delegation Discovery System Part One: The Comprehensive DDDSOctober 2002DDDS
Dynamic Delegation Discovery System Part Two: The AlgorithmOctober 2002DDDS
Dynamic Delegation Discovery System Part Three: The Domain Name System DatabaseOctober 2002DDDS
Dynamic Delegation Discovery System Part Four: The Uniform Resource Identifiers Resolution ApplicationOctober 2002DDDS
Dynamic Delegation Discovery System Part Five: URI.ARPA Assignment ProceduresOctober 2002DDDS
Punycode: A Bootstring encoding of Unicode for Internationalized Domain Names in Applications March 2003Punycode
INTERNET MESSAGE ACCESS PROTOCOL - VERSION 4rev1March 2003IMAP v 4r1
Network File System version 4 ProtocolApril 2003NFS v 4RFC 7530
Secure Electronic Transaction Supplement for the v1.0 Internet Open Trading Protocol June 2003Internet Open Trading Protocol
RTP: A Transport Protocol for Real-Time ApplicationsJuly 2003RTP
The Secure Real-time Transport Protocol March 2004SRTP
Internet Small Computer Systems Interface April 2004ISCSI
Extensible Provisioning Protocol March 2004Extensible Provisioning Protocol
Small Computer Systems Interface Command Ordering Considerations with iSCSIMay 2004ISCSI
Voice Profile for Internet ProtocolJune 2004VPIM
MIKEY: Multimedia Internet KEYingAugust 2004MIKEY
Payment Application Programmers Interface for v1.0November 2004Internet Open Trading Protocol
Network News Transfer ProtocolOctober 2006NNTP
The Kerberos Version 5 - Generic Security Service Application Program Interface July 2005Kerberos
A Universally Unique IDentifier URN NamespaceJuly 2005UUID
The 'tag' URI SchemeOctober 2005Tag URI scheme
Basic Transition Mechanisms for IPv6 Hosts and RoutersOctober 20056in4
Securing FTP with TLSOctober 2005SSL FTP (FTPS)
Border Gateway Protocol 4January 2006Border Gateway Protocol
The Atom Syndication FormatDecember 2005Atom
The Secure Shell Protocol ArchitectureJanuary 2006SSH-2
IP Version 6 Addressing ArchitectureFebruary 2006IPv6
A Framework for Conferencing with the Session Initiation Protocol February 2006Conference call
Sender Policy Framework for Authorizing Use of Domains in E-Mail, Version 1January 2006SPF
Simple Authentication and Security Layer June 2006SASL
Considerations for Internet Group Management Protocol and Multicast Listener Discovery Snooping SwitchesMay 2006IGMP snooping
A Session Initiation Protocol Event Package for Conference StateAugust 2006Conference call
Session Initiation Protocol Call Control - Conferencing for User AgentsAugust 2006Conference call
RFC 6234US Secure Hash Algorithms July 2006SHA-1, SHA-2
A Path Computation Element -Based ArchitectureAugust 2008 Path computation element
Network Address Translation Behavioral Requirements for Unicast UDPJanuary 2007NAT
Stream Control Transmission ProtocolSeptember 2007SCTP
The Atom Publishing ProtocolOctober 2007Atom
Sieve: An Email Filtering LanguageJanuary 2008SieveObsoletes RFC 3028
Simple Mail Transfer ProtocolOctober 2008SMTP, Internet Message Format
Internet Message FormatOctober 2008SMTP, Internet Message Format
Shim6: Level 3 Multihoming Shim Protocol for IPv6June 2009Site Multihoming by IPv6 Intermediation
iCalendar SpecificationSeptember 2009iCalendar
Tags for Identifying LanguagesSeptember 2009language tags
The OAuth 1.0 ProtocolApril 2010OAuth
Bidirectional Forwarding DetectionJune 2010BFD
BFD for IPv4 and IPv6 June 2010BFD
Network Time Protocol Version 4: Protocol and Algorithms SpecificationJune 2010NTP v 4Obsoletes RFC 1305, RFC 4330
IPv6 Rapid Deployment on IPv4 Infrastructures January 2010IPv6 rapid deployment
TOTP: Time-Based One-Time Password AlgorithmMay 2011TOTP
HTTP State Management MechanismApril 2011HTTP cookie
Message submission for mailNovember 2011message submission agentreplaces 2476, 4409
The WebSocket ProtocolDecember 2011WebSocket
Sakai-Kasahara Key Encryption February 2012SAKKE
Definition of the Opus Audio CodecSeptember 2012Opus (audio format)Updated by RFC 8251
File Delivery over Unidirectional Transport November 2012FLUTEObsoletes RFC 3926
The OAuth 2.0 Authorization FrameworkOctober 2012OAuth
HTTP Strict Transport Security November 2012HTTP Strict Transport Security
The Application of the Path Computation Element Architecture to the Determination of a Sequence of Domains in MPLS and GMPLSNovember 2012Path computation element
Hypertext Transfer Protocol : Message Syntax and RoutingJune 2014HTTP v1.1Obsoletes 2616
Hypertext Transfer Protocol : Semantics and ContentJune 2014HTTP v1.1Obsoletes 2616
Hypertext Transfer Protocol : Conditional RequestsJune 2014HTTP v1.1Obsoletes 2616
Hypertext Transfer Protocol : Range RequestsJune 2014HTTP v1.1, Byte servingObsoletes 2616
Hypertext Transfer Protocol : CachingJune 2014HTTP v1.1Obsoletes 2616
Hypertext Transfer Protocol : AuthenticationJune 2014HTTP v1.1Obsoletes 2616
Constrained Application Protocol June 2014Constrained Application Protocol
Transport Layer Security : Application-Layer Protocol Negotiation ExtensionJuly 2014Application-Layer Protocol Negotiation
Virtual eXtensible Local Area Network : A Framework for Overlaying Virtualized Layer 2 Networks over Layer 3 NetworksAugust 2014VXLAN
Public Key Pinning Extension for HTTPApril 2015HTTP Public Key Pinning
Network File System version 4 ProtocolMarch 2015NFS v 4
Hypertext Transfer Protocol Version 2 May 2015HTTP/2
HPACK: Header Compression for HTTP/2May 2015HTTP/2
IETF Recommendations Regarding Active Queue ManagementJuly 2015Active Queue Management
An HTTP Status Code to Report Legal ObstaclesDecember 2015HTTP 451
Client Subnet in DNS QueriesMay 2016Domain Name System
XMSS: eXtended Merkle Signature SchemeMay 2018Hash-based cryptography
CBOR Web Token May 2018
QUIC: A UDP-Based Multiplexed and Secure TransportMay 2021QUIC
Transmission Control Protocol August 2022TCPObsoletes RFC 793
CBOR Object Signing and Encryption : CountersignaturesDecember 2022COSEUpdates RFC 9052
The Messaging Layer Security ProtocolJuly 2023Messaging Layer Security
JSONPathFebruary 2024JSONPath
OpenPGPJuly 2024OpenPGPObsoletes RFC 4880, RFC 5581, RFC 6637

Topical list

Obsolete RFCs are indicated with struck-through text.
TopicRelated RFCs
Address Resolution ProtocolRFC 826
Blocks Extensible Exchange ProtocolRFC 3080
Bidirectional Forwarding DetectionRFC 5880, RFC 5881
BOOTPRFC 951
CRAM-MD5RFC 2195
Date and Time on the Internet RFC 3339
DEFLATERFC 1951
DISCARDRFC 863
Domain Name SystemRFC 1034, RFC 1035, RFC 2606, RFC 7871
Dynamic Delegation Discovery SystemRFC 2168, RFC 2915, RFC 3401, RFC 3402, RFC 3403, RFC 3404, RFC 3405
Dynamic Host Configuration ProtocolRFC 1531, RFC 1541, RFC 2131, RFC 3315
Extensible Messaging and Presence ProtocolRFC 3920 RFC 3921 RFC 3922
ECHO protocolRFC 862
Fictitious domain nameRFC 2606
File Transfer ProtocolRFC 114, RFC 172, RFC 265, RFC 354, RFC 765, RFC 959, RFC 2228, RFC 4217
Frame RelayRFC 1294, RFC 1490, RFC 2427
Generic Security Services Application Program InterfaceRFC 1508, RFC 1509, RFC 1964, RFC 2078, RFC 2743, RFC 2744, RFC 2853
gzipRFC 1952
HyperText Transfer ProtocolRFC 1945, RFC 2616, RFC 7230, RFC 7231, RFC 7232, RFC 7233, RFC 7234, RFC 7235
Internet Control Message ProtocolRFC 792
Internet Group Management ProtocolRFC 966, RFC 988, RFC 1054, 1112, RFC 2236, RFC 3376
Internet Key ExchangeIKE RFC 2409, RFC 2407, RFC 2408, IKEv2 RFC 4306, IKEv2 RFC 4301, RFC 4310
Internet Message Access ProtocolRFC 1176, RFC 1730, RFC 2060, RFC 3501
Internet Protocolsee IPv4 and IPv6
IP over Avian CarriersRFC 1149, RFC 2549
IPv4RFC 760, RFC 790, RFC 791
IPv6RFC 1883, RFC 2460, RFC 8200
IPv6 addressingRFC 2373, RFC 3513, RFC 4291
Internet Relay ChatRFC 1459, RFC 2810, RFC 2811, RFC 2812, RFC 2813
Internet Open Trading ProtocolRFC 2801, RFC 3504, RFC 2802, RFC 2935, RFC 3538, RFC 3867
ISCSIRFC 3720, RFC 3783
KerberosRFC 1964
Lightweight Directory Access ProtocolRFC 1487, RFC 1777, RFC 2251, RFC 2252, RFC 2253, RFC 2254, RFC 2255, RFC 2256, RFC 4510, RFC 4511, RFC 4512, RFC 4513, RFC 4514, RFC 4515, RFC 4516, RFC 4517, RFC 4518, RFC 4519, RFC 4520, RFC 4521, RFC 4522, RFC 4523, RFC 4524, RFC 4525, RFC 4526, RFC 4527, RFC 4528, RFC 4529, RFC 4530, RFC 4531, RFC 4532, RFC 4533, RFC 4534
Microsoft Point-to-Point EncryptionRFC 2118, RFC 3078
MIKEYRFC 3830, RFC 4650, RFC 4738, RFC 6043, RFC 6267, RFC 6509
MD5RFC 1321
Multiprotocol Label SwitchingRFC 3031
Multipurpose Internet Mail ExtensionsRFC 2045 RFC 2046 RFC 2047 RFC 2049
Network address translationRFC 1631, RFC 2663, RFC 2993, RFC 3022, RFC 3027, RFC 3234, RFC 3489, RFC 4787, RFC 5389
Network File SystemRFC 1094, RFC 1813, RFC 3010, RFC 3530, RFC 7530
Network News Transfer ProtocolRFC 977, RFC 3977
Network Time ProtocolRFC 1059, RFC 1119, RFC 1305, RFC 5905
Open Shortest Path FirstRFC 1131, RFC 1247, RFC 1583, RFC 2178, RFC 2328, RFC 2740, RFC 5340
Pretty Good PrivacyRFC 1991, RFC 2440, RFC 4880
Protocol Independent MulticastRFC 2117, RFC 2362, RFC 4602
Reverse Address Resolution ProtocolRFC 903
QUICRFC 9000
Post Office ProtocolRFC 918, RFC 937, RFC 1081, RFC 1225, RFC 1460, RFC 1725, RFC 1939
RADIUSRFC 2058, RFC 2059, RFC 2138, RFC 2139, RFC 2865, RFC 2866, RFC 2867, RFC 2868, RFC 2869, RFC 3162
Real-time Transport ProtocolRFC 1889
Real Time Streaming ProtocolRFC 2326
Routing Information ProtocolRFC 1058, RFC 1388, RFC 1723, RFC 2453, RFC 2080
Sender Policy FrameworkRFC 4408
Secure Shell-2RFC 4251
Session Announcement ProtocolRFC 2974
Session Description ProtocolRFC 2327
Session Initiation ProtocolRFC 3261
SHA hash functionsRFC 3174, RFC 4634, RFC 6234
Simple Authentication and Security LayerRFC 2222, RFC 4422
Simple Mail Transfer Protocol,
Internet Message Format
RFC 196, RFC 772, RFC 821, RFC 822, RFC 2821, RFC 2822, RFC 5321, RFC 5322
Simple Network Management ProtocolRFC 1067, RFC 1098, RFC 1157, RFC 1441 RFC 2570
Stream Control Transmission ProtocolRFC 2960, RFC 4960, RFC 3286
Tag URI schemeRFC 4151
TELNETRFC 15, RFC 854, RFC 855
Transmission Control ProtocolRFC 675, RFC 793, RFC 9293
Transport Layer Security 1.0RFC 2246
Trivial File Transfer ProtocolRFC 783, RFC 1350
UsenetRFC 850, RFC 1036
Uniform Resource IdentifierRFC 3986
User Datagram ProtocolRFC 768
UTF-8RFC 3629
zlibRFC 1950