RFC Errata

Errata Search

Source of RFC  
Summary Table Full Records

RFC 793, "Transmission Control Protocol", September 1981

Note: This RFC has been obsoleted by RFC 9293

Note: This RFC has been updated by RFC 1122, RFC 3168, RFC 6093, RFC 6528

Source of RFC: Legacy
Area Assignment: tsv

Errata ID: 3972
Status: Rejected
Type: Technical
Publication Format(s) : TEXT

Reported By: Richard Scheffenegger
Date Reported: 2014-04-23
Rejected by: Martin Stiemerling
Date Rejected: 2014-04-24

Section 3.1 says:

 Reserved:  6 bits

    Reserved for future use.  Must be zero.

It should say:

 Reserved:  6 bits

    Reserved for future use.  SHOULD be zero.


RFC3168 specifies 2 additional bits (ECE and CWR), RFC3540 specifies one additional bit (NS). Even though RFC793 predates RFC2119, and section 2.10 states
" be conservative in what you do, be liberal in what you accept from others.", any
update to this RFC should adjust the wording apropriately.
The text is correct, as is. For implementations implementing RFC 793 purely the have to set this to zero.

Report New Errata

Advanced Search