RFC 821. Simple Mail Transfer Protocol. J. Postel. August 1982.
RFC 876. Survey of SMTP implementations. D. Smallberg. Sep-01-1983.
(Status: UNKNOWN)
RFC 1047. Duplicate Messages and SMTP. Craig Partridge. February 1988.
RFC 1090. SMTP on X.25. R. Ullmann. Feb-01-1989. (Status: UNKNOWN)
RFC 1425. SMTP Service Extensions.
J. Klensin, WG Chair, N. Freed, Editor, M. Rose,E. Stefferud and D. Crocker.
February 1993.
(Obsoleted by RFC1651) (Status: PROPOSED STANDARD)
RFC 1426. SMTP Service Extension for 8bit-MIMEtransport.
J. Klensin, WG Chair, N. Freed, Editor, M. Rose, E. Stefferud and D. Crocker.
February 1993. (Obsoleted by RFC1652) (Status: PROPOSED STANDARD)
RFC 1427. SMTP Service Extension for Message Size Declaration.
J. Klensin, WG Chair, N. Freed, Editor, K. Moore. February 1993.
(Obsoleted by RFC1653) (Status: PROPOSED STANDARD)
RFC 1651. SMTP Service Extensions.
Klensin, N. Freed, M. Rose, E. Stefferud and D. Crocker. July 1994.
(Obsoletes RFC1425) (Obsoleted by RFC1869, STD0010) (Status: DRAFT STANDARD)
RFC 1652. SMTP Service Extension for 8bit-MIMEtransport.
Klensin, N. Freed, M. Rose, E. Stefferud and D. Crocker. July 1994.
(Obsoletes RFC1426) (Status: DRAFT STANDARD)
RFC 1653. SMTP Service Extension for Message Size Declaration.
J. Klensin, N. Freed and K. Moore. July 1994. (Obsoletes RFC1427)
(Obsoleted by RFC1870, STD0011) (Status: DRAFT STANDARD)
RFC 1830. SMTP Service Extensions for Transmission of Large and Binary
MIME Messages. G. Vaudreuil. August 1995.
RFC1845 SMTP Service Extension for Checkpoint/Restart. D. Crocker, N. Freed
and A. Cargille. September 1995.
RFC 1846. SMTP 521 Reply Code. A. Durand and F. Dupont. September 1995.
RFC 1854. SMTP Service Extension for Command Pipelining.
N. Freed. October 1995. (Obsoleted by RFC2197)
RFC 1869. SMTP Service Extensions.
J. Klensin, N. Freed, M. Rose, E. Stefferud and D. Crocker. November 1995.
(Obsoletes RFC1651) (Also STD0010) (Status: STANDARD)
RFC 1870. SMTP Service Extension for Message Size Declaration.
J. Klensin, N. Freed, and K. Moore. November 1995.
(Obsoletes RFC1653) (Also STD0010) (Status: STANDARD)
RFC 1891. SMTP Service Extension for Delivery Status Notifications.
K. Moore. January 1996. (Status: PROPOSED STANDARD)
RFC 1985. SMTP Service Extension for Remote Message Queue Starting.
J. De Winter. August 1996. (Status: PROPOSED STANDARD)
RFC 2034. SMTP Service Extension for Returning Enhanced Error Codes.
N. Freed. October 1996. (Status: PROPOSED STANDARD)
RFC 2197. SMTP Service Extension for Command Pipelining.
N. Freed. September 1997.
(Obsoletes RFC1854) (Status: DRAFT STANDARD)
RFC 2442. The Batch SMTP Media Type.
N. Freed, D. Newman, J. Belissen, M. Hoy.
November 1998.
RFC 2487. SMTP Service Extension for Secure SMTP over TLS.
P. Hoffman. January 1999.
RFC 2505. Anti-Spam Recommendations for SMTP MTA.
G. Lindberg. February 1999.
RFC 2554. SMTP Service Extension for Authentication.
J. Myers. March 1999.
RFC 2645. ON-DEMAND MAIL RELAY (ODMR) SMTP with Dynamic IP Addresses.
R. Gellens. August 1999.
RFC 2821. Klensin, J., "Simple Mail Transfer Protocol", April 2001.
(Obsoletes RFC0821, RFC0974, RFC1869)
RFC 2852. Deliver By SMTP Service Extension. D. Newman. June 2000.
(Updates RFC1894)
RFC 2920. SMTP Service Extension for Command Pipelining. N. Freed.
September 2000. (Obsoletes RFC2197) (Also STD0060) (Status: STANDARD)
RFC 3030. SMTP Service Extensions for Transmission of Large and Binary MIME
Messages. G. Vaudreuil. December 2000.
(Obsoletes RFC1830)
RFC 3207. SMTP Service Extension for Secure SMTP over Transport Layer
Security. P. Hoffman. February 2002. (Obsoletes RFC2487)