TCP Processing of the IPv4 Precedence Field
draft-xiao-tcp-prec-03

A new Request for Comments is now available in online RFC libraries.

        RFC 2873

        Title:      TCP Processing of the IPv4 Precedence Field
        Author(s):  X. Xiao, A. Hannan, V. Paxson, E. Crabbe
        Status:     Standards Track
        Date:       June 2000
        Mailbox:    xipeng@gblx.net, alan@ivmg.net,
                    edc@explosive.net, vern@aciri.org  
        Pages:      8
        Characters: 15565
        Updates/Obsoletes/SeeAlso:  None

        I-D Tag:    draft-xiao-tcp-prec-03.txt

        URL:        ftp://ftp.isi.edu/in-notes/rfc2873.txt

This memo describes a conflict between TCP [RFC793] and DiffServ
[RFC2475] on the use of the three leftmost bits in the TOS octet of
an IPv4 header [RFC791]. In a network that contains DiffServ-capable
nodes, such a conflict can cause failures in establishing TCP
connections or can cause some established TCP connections to be reset
undesirably. This memo proposes a modification to TCP for resolving
the conflict.

Because the IPv6 [RFC2460] traffic class octet does not have any
defined meaning except what is defined in RFC 2474, and in particular
does not define precedence or security parameter bits, there is no
conflict between TCP and DiffServ on the use of any bits in the IPv6
traffic class octet.

This is now a Proposed Standard Protocol.

This document specifies an Internet standards track protocol for
the Internet community, and requests discussion and suggestions
for improvements.  Please refer to the current edition of the
"Internet Official Protocol Standards" (STD 1) for the
standardization state and status of this protocol.  Distribution
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