RFC 2836 (rfc2836) - Page 1 of 7
Per Hop Behavior Identification Codes
Alternative Format: Original Text Document
Network Working Group S. Brim
Request for Comments: 2836 B. Carpenter
Category: Standards Track F. Le Faucheur
May 2000
Per Hop Behavior Identification Codes
Status of this Memo
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 of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2000). All Rights Reserved.
Table of Contents:
1. Introduction................................................. 1
1.1. Usage Scenarios............................................ 2
2. Encoding..................................................... 3
3. IANA Considerations.......................................... 4
4. Security considerations...................................... 4
References...................................................... 4
Authors' Addresses.............................................. 5
Intellectual Property........................................... 6
Full Copyright Statement........................................ 7
1. Introduction
Differentiated Services [RFC 2474, RFC 2475] introduces the notion of
Per Hop Behaviors (PHBs) that define how traffic belonging to a
particular behavior aggregate is treated at an individual network
node. In IP packet headers, PHBs are not indicated as such; instead
Differentiated Services Codepoint (DSCP) values are used. There are
only 64 possible DSCP values, but there is no such limit on the
number of PHBs. In a given network domain, there is a locally defined
mapping between DSCP values and PHBs. Standardized PHBs recommend a
DSCP mapping, but network operators may choose alternative mappings.
Brim, et al. Standards Track
