| 1 | Host SoftwareS. Crocker | Unknown | April 1969 |
| 1004 | Distributed-protocol authentication schemeD.L. Mills | Experimental | April 1987 |
| 1411 | Telnet Authentication: Kerberos Version 4D. Borman, Ed. | Experimental | January 1993 |
| 1412 | Telnet Authentication: SPXK. Alagappan | Experimental | January 1993 |
| 1413 | Identification ProtocolM. St. Johns | Proposed Standard | February 1993 |
| 1421 | Privacy Enhancement for Internet Electronic Mail: Part I: Message Encryption and Authentication ProceduresJ. Linn | Historic | February 1993 |
| 1422 | Privacy Enhancement for Internet Electronic Mail: Part II: Certificate-Based Key ManagementS. Kent | Historic | February 1993 |
| 1423 | Privacy Enhancement for Internet Electronic Mail: Part III: Algorithms, Modes, and IdentifiersD. Balenson | Historic | February 1993 |
| 1424 | Privacy Enhancement for Internet Electronic Mail: Part IV: Key Certification and Related ServicesB. Kaliski | Historic | February 1993 |
| 1507 | DASS - Distributed Authentication Security ServiceC. Kaufman | Experimental | September 1993 |
| 1510 | The Kerberos Network Authentication Service (V5)J. Kohl, C. Neuman · obsoleted by RFC 4120, RFC 6649 | Historic | September 1993 |
| 1731 | IMAP4 Authentication MechanismsJ. Myers | Proposed Standard | December 1994 |
| 1734 | POP3 AUTHentication commandJ. Myers · obsoleted by RFC 5034 | Proposed Standard | December 1994 |
| 1828 | IP Authentication using Keyed MD5P. Metzger, W. Simpson | Historic | August 1995 |
| 1829 | The ESP DES-CBC TransformP. Karn, P. Metzger, W. Simpson | Proposed Standard | August 1995 |
| 1847 | Security Multiparts for MIME: Multipart/Signed and Multipart/EncryptedJ. Galvin, S. Murphy, S. Crocker, N. Freed | Proposed Standard | October 1995 |
| 1848 | MIME Object Security ServicesS. Crocker, N. Freed, J. Galvin, S. Murphy | Historic | October 1995 |
| 1851 | The ESP Triple DES TransformP. Karn, P. Metzger, W. Simpson | Experimental | September 1995 |
| 1864 | The Content-MD5 Header FieldJ. Myers, M. Rose | Draft Standard | October 1995 |
| 1928 | SOCKS Protocol Version 5M. Leech, M. Ganis, Y. Lee, R. Kuris, D. Koblas, L. Jones | Proposed Standard | March 1996 |
| 1929 | Username/Password Authentication for SOCKS V5M. Leech | Proposed Standard | March 1996 |
| 1949 | Scalable Multicast Key DistributionA. Ballardie | Experimental | May 1996 |
| 1961 | GSS-API Authentication Method for SOCKS Version 5P. McMahon | Proposed Standard | June 1996 |
| 1964 | The Kerberos Version 5 GSS-API MechanismJ. Linn | Proposed Standard | June 1996 |
| 1968 | The PPP Encryption Control Protocol (ECP)G. Meyer | Proposed Standard | June 1996 |
| 2015 | MIME Security with Pretty Good Privacy (PGP)M. Elkins | Proposed Standard | October 1996 |
| 2025 | The Simple Public-Key GSS-API Mechanism (SPKM)C. Adams | Proposed Standard | October 1996 |
| 2082 | RIP-2 MD5 AuthenticationF. Baker, R. Atkinson · obsoleted by RFC 4822 | Proposed Standard | January 1997 |
| 2085 | HMAC-MD5 IP Authentication with Replay PreventionM. Oehler, R. Glenn | Proposed Standard | February 1997 |
| 2093 | Group Key Management Protocol (GKMP) SpecificationH. Harney, C. Muckenhirn | Experimental | July 1997 |
| 2094 | Group Key Management Protocol (GKMP) ArchitectureH. Harney, C. Muckenhirn | Experimental | July 1997 |
| 2154 | OSPF with Digital SignaturesS. Murphy, M. Badger, B. Wellington | Experimental | June 1997 |
| 2195 | IMAP/POP AUTHorize Extension for Simple Challenge/ResponseJ. Klensin, R. Catoe, P. Krumviede | Proposed Standard | September 1997 |
| 2203 | RPCSEC_GSS Protocol SpecificationM. Eisler, A. Chiu, L. Ling | Proposed Standard | September 1997 |
| 2222 | Simple Authentication and Security Layer (SASL)J. Myers · obsoleted by RFC 4422, RFC 4752 | Proposed Standard | October 1997 |
| 2228 | FTP Security ExtensionsM. Horowitz, S. Lunt | Proposed Standard | October 1997 |
| 2243 | OTP Extended ResponsesC. Metz | Proposed Standard | November 1997 |
| 2245 | Anonymous SASL MechanismC. Newman · obsoleted by RFC 4505 | Proposed Standard | November 1997 |
| 2246 | The TLS Protocol Version 1.0T. Dierks, C. Allen · obsoleted by RFC 4346 | Historic | January 1999 |
| 2284 | PPP Extensible Authentication Protocol (EAP)L. Blunk, J. Vollbrecht · obsoleted by RFC 3748 | Proposed Standard | March 1998 |
| 2289 | A One-Time Password SystemN. Haller, C. Metz, P. Nesser, M. Straw | Internet Standard | February 1998 |
| 2385 | Protection of BGP Sessions via the TCP MD5 Signature OptionA. Heffernan · obsoleted by RFC 5925 | Proposed Standard | August 1998 |
| 2401 | Security Architecture for the Internet ProtocolS. Kent, R. Atkinson · obsoleted by RFC 4301 | Proposed Standard | November 1998 |
| 2402 | IP Authentication HeaderS. Kent, R. Atkinson · obsoleted by RFC 4302, RFC 4305 | Proposed Standard | November 1998 |
| 2403 | The Use of HMAC-MD5-96 within ESP and AHC. Madson, R. Glenn | Proposed Standard | November 1998 |
| 2404 | The Use of HMAC-SHA-1-96 within ESP and AHC. Madson, R. Glenn | Proposed Standard | November 1998 |
| 2405 | The ESP DES-CBC Cipher Algorithm With Explicit IVC. Madson, N. Doraswamy | Proposed Standard | November 1998 |
| 2406 | IP Encapsulating Security Payload (ESP)S. Kent, R. Atkinson · obsoleted by RFC 4303, RFC 4305 | Proposed Standard | November 1998 |
| 2407 | The Internet IP Security Domain of Interpretation for ISAKMPD. Piper · obsoleted by RFC 4306 | Historic | November 1998 |
| 2408 | Internet Security Association and Key Management Protocol (ISAKMP)D. Maughan, M. Schertler, M. Schneider, J. Turner · obsoleted by RFC 4306 | Historic | November 1998 |
| 2409 | The Internet Key Exchange (IKE)D. Harkins, D. Carrel · obsoleted by RFC 4306 | Historic | November 1998 |
| 2410 | The NULL Encryption Algorithm and Its Use With IPsecR. Glenn, S. Kent | Proposed Standard | November 1998 |
| 2419 | The PPP DES Encryption Protocol, Version 2 (DESE-bis)K. Sklower, G. Meyer | Proposed Standard | September 1998 |
| 2420 | The PPP Triple-DES Encryption Protocol (3DESE)H. Kummert | Proposed Standard | September 1998 |
| 2440 | OpenPGP Message FormatJ. Callas, L. Donnerhacke, H. Finney, R. Thayer · obsoleted by RFC 4880 | Proposed Standard | November 1998 |
| 2444 | The One-Time-Password SASL MechanismC. Newman | Proposed Standard | October 1998 |
| 2451 | The ESP CBC-Mode Cipher AlgorithmsR. Pereira, R. Adams | Proposed Standard | November 1998 |
| 2459 | Internet X.509 Public Key Infrastructure Certificate and CRL ProfileR. Housley, W. Ford, W. Polk, D. Solo · obsoleted by RFC 3280 | Proposed Standard | January 1999 |
| 2478 | The Simple and Protected GSS-API Negotiation MechanismE. Baize, D. Pinkas · obsoleted by RFC 4178 | Proposed Standard | December 1998 |
| 2510 | Internet X.509 Public Key Infrastructure Certificate Management ProtocolsC. Adams, S. Farrell · obsoleted by RFC 4210 | Proposed Standard | March 1999 |
| 2511 | Internet X.509 Certificate Request Message FormatM. Myers, C. Adams, D. Solo, D. Kemp · obsoleted by RFC 4211 | Proposed Standard | March 1999 |
| 2522 | Photuris: Session-Key Management ProtocolP. Karn, W. Simpson | Experimental | March 1999 |
| 2523 | Photuris: Extended Schemes and AttributesP. Karn, W. Simpson | Experimental | March 1999 |
| 2535 | Domain Name System Security ExtensionsD. Eastlake 3rd · obsoleted by RFC 4033, RFC 4034, RFC 4035 | Proposed Standard | March 1999 |
| 2536 | DSA KEYs and SIGs in the Domain Name System (DNS)D. Eastlake 3rd | Proposed Standard | March 1999 |
| 2538 | Storing Certificates in the Domain Name System (DNS)D. Eastlake 3rd, O. Gudmundsson · obsoleted by RFC 4398 | Proposed Standard | March 1999 |
| 2539 | Storage of Diffie-Hellman Keys in the Domain Name System (DNS)D. Eastlake 3rd | Proposed Standard | March 1999 |
| 2560 | X.509 Internet Public Key Infrastructure Online Certificate Status Protocol - OCSPM. Myers, R. Ankney, A. Malpani, S. Galperin, C. Adams · obsoleted by RFC 6960 | Proposed Standard | June 1999 |
| 2585 | Internet X.509 Public Key Infrastructure Operational Protocols: FTP and HTTPR. Housley, P. Hoffman | Proposed Standard | May 1999 |
| 2587 | Internet X.509 Public Key Infrastructure LDAPv2 SchemaS. Boeyen, T. Howes, P. Richard · obsoleted by RFC 4523 | Proposed Standard | June 1999 |
| 2617 | HTTP Authentication: Basic and Digest Access AuthenticationJ. Franks, P. Hallam-Baker, J. Hostetler, S. Lawrence, P. Leach, A. Luotonen, L. Stewart · obsoleted by RFC 7235, RFC 7615, RFC 7616, RFC 7617 | Draft Standard | June 1999 |
| 2623 | NFS Version 2 and Version 3 Security Issues and the NFS Protocol's Use of RPCSEC_GSS and Kerberos V5M. Eisler | Proposed Standard | June 1999 |
| 2631 | Diffie-Hellman Key Agreement MethodE. Rescorla | Proposed Standard | June 1999 |
| 2632 | S/MIME Version 3 Certificate HandlingB. Ramsdell, Ed. · obsoleted by RFC 3850 | Proposed Standard | June 1999 |
| 2633 | S/MIME Version 3 Message SpecificationB. Ramsdell, Ed. · obsoleted by RFC 3851 | Proposed Standard | June 1999 |
| 2634 | Enhanced Security Services for S/MIMEP. Hoffman, Ed. | Proposed Standard | June 1999 |
| 2659 | Security Extensions For HTMLE. Rescorla, A. Schiffman | Experimental | August 1999 |
| 2660 | The Secure HyperText Transfer ProtocolE. Rescorla, A. Schiffman | Historic | August 1999 |
| 2692 | SPKI RequirementsC. Ellison | Experimental | September 1999 |
| 2693 | SPKI Certificate TheoryC. Ellison, B. Frantz, B. Lampson, R. Rivest, B. Thomas, T. Ylonen | Experimental | September 1999 |
| 2712 | Addition of Kerberos Cipher Suites to Transport Layer Security (TLS)A. Medvinsky, M. Hur | Proposed Standard | October 1999 |
| 2716 | PPP EAP TLS Authentication ProtocolB. Aboba, D. Simon · obsoleted by RFC 5216 | Experimental | October 1999 |
| 2743 | Generic Security Service Application Program Interface Version 2, Update 1J. Linn | Proposed Standard | January 2000 |
| 2744 | Generic Security Service API Version 2 : C-bindingsJ. Wray | Proposed Standard | January 2000 |
| 2747 | RSVP Cryptographic AuthenticationF. Baker, B. Lindell, M. Talwar | Proposed Standard | January 2000 |
| 2773 | Encryption using KEA and SKIPJACKR. Housley, P. Yee, W. Nace | Experimental | February 2000 |
| 2797 | Certificate Management Messages over CMSM. Myers, X. Liu, J. Schaad, J. Weinstein · obsoleted by RFC 5272 | Proposed Standard | April 2000 |
| 2817 | Upgrading to TLS Within HTTP/1.1R. Khare, S. Lawrence | Proposed Standard | May 2000 |
| 2829 | Authentication Methods for LDAPM. Wahl, H. Alvestrand, J. Hodges, R. Morgan · obsoleted by RFC 4510, RFC 4513 | Proposed Standard | May 2000 |
| 2830 | Lightweight Directory Access Protocol (v3): Extension for Transport Layer SecurityJ. Hodges, R. Morgan, M. Wahl · obsoleted by RFC 4510, RFC 4511, RFC 4513 | Proposed Standard | May 2000 |
| 2831 | Using Digest Authentication as a SASL MechanismP. Leach, C. Newman · obsoleted by RFC 6331 | Historic | May 2000 |
| 2845 | Secret Key Transaction Authentication for DNS (TSIG)P. Vixie, O. Gudmundsson, D. Eastlake 3rd, B. Wellington · obsoleted by RFC 8945 | Proposed Standard | May 2000 |
| 2847 | LIPKEY - A Low Infrastructure Public Key Mechanism Using SPKMM. Eisler | Proposed Standard | June 2000 |
| 2853 | Generic Security Service API Version 2 : Java BindingsJ. Kabat, M. Upadhyay · obsoleted by RFC 5653 | Proposed Standard | June 2000 |
| 2857 | The Use of HMAC-RIPEMD-160-96 within ESP and AHA. Keromytis, N. Provos | Proposed Standard | June 2000 |
| 2865 | Remote Authentication Dial In User Service (RADIUS)C. Rigney, S. Willens, A. Rubens, W. Simpson | Draft Standard | June 2000 |
| 2875 | Diffie-Hellman Proof-of-Possession AlgorithmsH. Prafullchandra, J. Schaad · obsoleted by RFC 6955 | Proposed Standard | July 2000 |
| 2930 | Secret Key Establishment for DNS (TKEY RR)D. Eastlake 3rd | Proposed Standard | September 2000 |
| 2931 | DNS Request and Transaction Signatures ( SIG(0)s )D. Eastlake 3rd | Proposed Standard | September 2000 |
| 2935 | Internet Open Trading Protocol (IOTP) HTTP SupplementD. Eastlake 3rd, C. Smith | Proposed Standard | September 2000 |
| 2941 | Telnet Authentication OptionT. Ts'o, Ed., J. Altman | Proposed Standard | September 2000 |
| 2942 | Telnet Authentication: Kerberos Version 5T. Ts'o | Proposed Standard | September 2000 |
| 2943 | TELNET Authentication Using DSAR. Housley, T. Horting, P. Yee | Proposed Standard | September 2000 |
| 2944 | Telnet Authentication: SRPT. Wu | Proposed Standard | September 2000 |
| 2945 | The SRP Authentication and Key Exchange SystemT. Wu | Proposed Standard | September 2000 |
| 2946 | Telnet Data Encryption OptionT. Ts'o | Proposed Standard | September 2000 |
| 2947 | Telnet Encryption: DES3 64 bit Cipher FeedbackJ. Altman | Proposed Standard | September 2000 |
| 2948 | Telnet Encryption: DES3 64 bit Output FeedbackJ. Altman | Proposed Standard | September 2000 |
| 2949 | Telnet Encryption: CAST-128 64 bit Output FeedbackJ. Altman | Proposed Standard | September 2000 |
| 2950 | Telnet Encryption: CAST-128 64 bit Cipher FeedbackJ. Altman | Proposed Standard | September 2000 |
| 2984 | Use of the CAST-128 Encryption Algorithm in CMSC. Adams | Proposed Standard | October 2000 |
| 3007 | Secure Domain Name System (DNS) Dynamic UpdateB. Wellington | Proposed Standard | November 2000 |
| 3008 | Domain Name System Security (DNSSEC) Signing AuthorityB. Wellington · obsoleted by RFC 4033, RFC 4034, RFC 4035 | Proposed Standard | November 2000 |
| 3012 | Mobile IPv4 Challenge/Response ExtensionsC. Perkins, P. Calhoun · obsoleted by RFC 4721 | Proposed Standard | November 2000 |
| 3029 | Internet X.509 Public Key Infrastructure Data Validation and Certification Server ProtocolsC. Adams, P. Sylvester, M. Zolotarev, R. Zuccherato | Experimental | February 2001 |
| 3039 | Internet X.509 Public Key Infrastructure Qualified Certificates ProfileS. Santesson, W. Polk, P. Barzin, M. Nystrom · obsoleted by RFC 3739 | Proposed Standard | January 2001 |
| 3041 | Privacy Extensions for Stateless Address Autoconfiguration in IPv6T. Narten, R. Draves · obsoleted by RFC 4941 | Proposed Standard | January 2001 |
| 3062 | LDAP Password Modify Extended OperationK. Zeilenga | Proposed Standard | February 2001 |
| 3090 | DNS Security Extension Clarification on Zone StatusE. Lewis · obsoleted by RFC 4033, RFC 4034, RFC 4035 | Proposed Standard | March 2001 |
| 3097 | RSVP Cryptographic Authentication -- Updated Message Type ValueR. Braden, L. Zhang | Proposed Standard | April 2001 |
| 3110 | RSA/SHA-1 SIGs and RSA KEYs in the Domain Name System (DNS)D. Eastlake 3rd | Proposed Standard | May 2001 |
| 3118 | Authentication for DHCP MessagesR. Droms, Ed., W. Arbaugh, Ed. | Proposed Standard | June 2001 |
| 3162 | RADIUS and IPv6B. Aboba, G. Zorn, D. Mitton | Proposed Standard | August 2001 |
| 3207 | SMTP Service Extension for Secure SMTP over Transport Layer SecurityP. Hoffman | Proposed Standard | February 2002 |
| 3275 | (Extensible Markup Language) XML-Signature Syntax and ProcessingD. Eastlake 3rd, J. Reagle, D. Solo | Draft Standard | March 2002 |
| 3280 | Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) ProfileR. Housley, W. Polk, W. Ford, D. Solo · obsoleted by RFC 5280 | Proposed Standard | May 2002 |
| 3315 | Dynamic Host Configuration Protocol for IPv6 (DHCPv6)R. Droms, Ed., J. Bound, B. Volz, T. Lemon, C. Perkins, M. Carney · obsoleted by RFC 8415 | Proposed Standard | July 2003 |
| 3369 | Cryptographic Message Syntax (CMS)R. Housley · obsoleted by RFC 3852 | Proposed Standard | September 2002 |
| 3789 | Introduction to the Survey of IPv4 Addresses in Currently Deployed IETF Standards Track and Experimental DocumentsP. Nesser, II, A. Bergstrom, Ed. | Informational | June 2004 |