A proposal for Backward ECN for the Internet Protocol (IPv4/IPv6)

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Last updated 1998-06-04
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This memo proposes an alternative approach to the current ECN mechanism as proposed in the internet draft [draft-kksjf]. A Backward-ECN(BECN) is proposed which uses the existing IP signalling mechanism, the Internet Control Messaging Protocol (ICMP) [RFC 792] Source Quench message. The use of ICMP Source Quench (ISQ) allows a basic ECN mechanism for IP which does not require any negotiation between end systems. Congestion notification is kept at the network(IP) level. The congestion state can be reflected up to the transport layer (e.g. TCP or UDP) for appropriate action. The ISQ based approach reduces the reaction time to a congestion in the network. In addition, the ISQ message can include information on the severity of the congestion allowing the end host to react accordingly so as to make maximal use of the resources while maintaining network equilibrium.


Biswajit Nandy (bnandy@nortel.ca)
Nabil Seddigh (nseddigh@nortel.ca)
Jamal Hadi Salim (hadi@znyx.com)

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