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A Proposal for the Format and Semantics of the TOS Byte and Traffic Class Byte in IPv4 and IPv6 Headers

Document Type Expired Internet-Draft (individual)
Expired & archived
Authors Ed J. Ellesson , Steven L. Blake
Last updated 1997-12-03
RFC stream (None)
Intended RFC status (None)
Stream Stream state (No stream defined)
Consensus boilerplate Unknown
RFC Editor Note (None)
IESG IESG state Expired
Telechat date (None)
Responsible AD (None)
Send notices to (None)

This Internet-Draft is no longer active. A copy of the expired Internet-Draft is available in these formats:


This draft proposes an arrangement of fields in the IPv4 TOS byte [RFC795, RFC1349], and in the IPv6 Traffic Class byte [IPv6], and proposes a definition for their associated semantics. The intention is to enable the preservation of currently useful differential class- based queueing behavior on existing network devices, while simultaneously enabling new methods of bandwidth allocation and policing via drop preference, all within the context of flows which may be encrypted at the IP layer using IPSEC. (Note: the IPv6 Class field has recently been expanded to eight bits, but this in not yet available in any version of the specification).


Ed J. Ellesson
Steven L. Blake

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)