Problem Statement and Requirements for a TCP Authentication Option

Document Type Expired Internet-Draft (individual in tsv area)
Author Steven Bellovin 
Last updated 2015-10-14 (latest revision 2007-07-12)
Stream Internet Engineering Task Force (IETF)
Intended RFC status (None)
Expired & archived
pdf htmlized (tools) htmlized bibtex
Stream WG state (None)
Document shepherd No shepherd assigned
IESG IESG state Expired (IESG: Dead)
Action Holders
Consensus Boilerplate Unknown
Telechat date
Responsible AD Lars Eggert
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This Internet-Draft is no longer active. A copy of the expired Internet-Draft can be found at


The TCP-MD5 option is commonly used to secure BGP sessions between routers, although it is known to have many serious deficiencies. This memo presents requirements for a TCP segment authentication mechanism that is intended to replace TCP-MD5. While TCP-MD5 was designed to protect TCP sessions whose payload is BGP, the applicability of the mechanism described herein is broader. This mechanism can be applied to any TCP connection, regardless of payload.


Steven Bellovin (

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