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ObsoletedINTERNET STANDARDLegacy stream

RFC 793: Transmission Control Protocol

This RFC has been replaced. Do not implement against it for new work — it was formally obsoleted by RFC 9293.

Current document in this lineage: RFC 7805 — Moving Outdated TCP Extensions and TCP-Related Documents to Historic or Informational Status; RFC 9293 — Transmission Control Protocol (TCP)

In plain English — editorial summary, not part of the RFC

RFC 793 defines TCP, the protocol that turns IP's unreliable packet delivery into a reliable, ordered byte stream between two programs. It specifies the three-way handshake (SYN, SYN-ACK, ACK) that opens a connection, sequence numbers and acknowledgements for retransmitting lost data, the sliding window used for flow control, and the connection teardown states you see in netstat output (TIME_WAIT, CLOSE_WAIT and the rest).

Document record

Document ID
RFC793
Published
September 1981
Authors
J. Postel
Status
INTERNET STANDARD
Stream
Legacy
Area
—
Pages
91
Also known as
—
Obsoletes:
RFC 761
Obsoleted by:
RFC 9293
Updated by:
RFC 1122, RFC 3168, RFC 6093, RFC 6528

Topics

Standards lineage

This document is one revision in a chain of 18 RFCs, each formally replacing the one before it.

  1. RFC 675 (1974)
  2. RFC 721 (1976)
  3. RFC 761 (1980)
  4. RFC 793 (1981)
  5. RFC 813 (1982)
  6. RFC 816 (1982)
  7. RFC 879 (1983)
  8. RFC 896 (1984)
  9. RFC 1078 (1988)
  10. RFC 1948 (1996)
  11. RFC 2873 (2000)
  12. RFC 6013 (2011)
  13. RFC 6093 (2011)
  14. RFC 6429 (2011)
  15. RFC 6528 (2012)
  16. RFC 6691 (2012)
  17. RFC 7805 (2016)
  18. RFC 9293 (2022) ✓

Read the full history of Transmission Control Protocol (TCP) →

Referenced by

5 later RFCs formally update or obsolete part of this document.

Related documents

Ranked automatically by shared keywords, IETF area and stream — not by editorial selection.

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About this page

The document record above — title, authors, date, status, stream, area, relationships, DOI and errata — is imported verbatim from the public RFC Editor index. The “in plain English” section is editorial: written by The metasystema editorial team, not part of the RFC. Where the two differ, the RFC text governs.

Last checked against the RFC Editor index on . RFCs are never revised after publication; changes are issued as new documents.

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canonical URL: /rfc/793-transmission-control-protocol