| 2104 | HMAC: Keyed-Hashing for Message AuthenticationH. Krawczyk, M. Bellare, R. Canetti | Informational | February 1997 |
| 2119 | Key words for use in RFCs to Indicate Requirement LevelsS. Bradner | Best Current Practice | March 1997 |
| 2743 | Generic Security Service Application Program Interface Version 2, Update 1J. Linn | Proposed Standard | January 2000 |
| 2865 | Remote Authentication Dial In User Service (RADIUS)C. Rigney, S. Willens, A. Rubens, W. Simpson | Draft Standard | June 2000 |
| 2898 | PKCS #5: Password-Based Cryptography Specification Version 2.0B. Kaliski · obsoleted by RFC 8018 | Informational | September 2000 |
| 2945 | The SRP Authentication and Key Exchange SystemT. Wu | Proposed Standard | September 2000 |
| 3174 | US Secure Hash Algorithm 1 (SHA1)D. Eastlake 3rd, P. Jones | Informational | September 2001 |
| 3454 | Preparation of Internationalized Strings ("stringprep")P. Hoffman, M. Blanchet · obsoleted by RFC 7564 | Proposed Standard | January 2003 |
| 3629 | UTF-8, a transformation format of ISO 10646F. Yergeau | Internet Standard | November 2003 |
| 3961 | Encryption and Checksum Specifications for Kerberos 5K. Raeburn | Proposed Standard | February 2005 |
| 3962 | Advanced Encryption Standard (AES) Encryption for Kerberos 5K. Raeburn | Proposed Standard | February 2005 |
| 4013 | SASLprep: Stringprep Profile for User Names and PasswordsK. Zeilenga · obsoleted by RFC 7613 | Proposed Standard | March 2005 |
| 4086 | Randomness Requirements for SecurityD. Eastlake 3rd, J. Schiller, S. Crocker | Best Current Practice | June 2005 |
| 4121 | The Kerberos Version 5 Generic Security Service Application Program Interface (GSS-API) Mechanism: Version 2L. Zhu, K. Jaganathan, S. Hartman | Proposed Standard | July 2005 |
| 4401 | A Pseudo-Random Function (PRF) API Extension for the Generic Security Service Application Program Interface (GSS-API)N. Williams | Proposed Standard | February 2006 |
| 4402 | A Pseudo-Random Function (PRF) for the Kerberos V Generic Security Service Application Program Interface (GSS-API) MechanismN. Williams · obsoleted by RFC 7802 | Historic | February 2006 |
| 4422 | Simple Authentication and Security Layer (SASL)A. Melnikov, Ed., K. Zeilenga, Ed. | Proposed Standard | June 2006 |
| 4510 | Lightweight Directory Access Protocol (LDAP): Technical Specification Road MapK. Zeilenga, Ed. | Proposed Standard | June 2006 |
| 4616 | The PLAIN Simple Authentication and Security Layer (SASL) MechanismK. Zeilenga, Ed. | Proposed Standard | August 2006 |
| 4648 | The Base16, Base32, and Base64 Data EncodingsS. Josefsson | Proposed Standard | October 2006 |
| 4949 | Internet Security Glossary, Version 2R. Shirey | Informational | August 2007 |
| 5056 | On the Use of Channel Bindings to Secure ChannelsN. Williams | Proposed Standard | November 2007 |
| 5226 | Guidelines for Writing an IANA Considerations Section in RFCsT. Narten, H. Alvestrand · obsoleted by RFC 8126 | Best Current Practice | May 2008 |
| 5234 | Augmented BNF for Syntax Specifications: ABNFD. Crocker, Ed., P. Overell | Internet Standard | January 2008 |
| 5246 | The Transport Layer Security (TLS) Protocol Version 1.2T. Dierks, E. Rescorla · obsoleted by RFC 8446, RFC 9846 | Proposed Standard | August 2008 |
| 5741 | RFC Streams, Headers, and BoilerplatesL. Daigle, Ed., O. Kolkman, Ed., IAB · obsoleted by RFC 7841 | Informational | December 2009 |
| 5801 | Using Generic Security Service Application Program Interface (GSS-API) Mechanisms in Simple Authentication and Security Layer (SASL): The GS2 Mechanism FamilyS. Josefsson, N. Williams | Proposed Standard | July 2010 |
| 5803 | Lightweight Directory Access Protocol (LDAP) Schema for Storing Salted Challenge Response Authentication Mechanism (SCRAM) SecretsA. Melnikov | Informational | July 2010 |
| 5929 | Channel Bindings for TLSJ. Altman, N. Williams, L. Zhu | Proposed Standard | July 2010 |