Ethereal-dev: [ethereal-dev] ECN = Explicit Congestion Notification

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From: Dax Kelson <dax@xxxxxxxxxxxx>
Date: Thu, 14 Sep 2000 13:29:39 -0600 (MDT)
RFC 2481 describes ECN:

http://www.faqs.org/rfcs/rfc2481.html

In a nutshell, here is how it works in IPv4:

ECN uses the two bits after the DiffServe field in the IP header, the
"CU" bits.

Bit 6 is designated as the ECT bit, and bit 7 is designated as the CE bit.


The first layer 4 protocol to get ECN support is TCP.

Bit 9 in the Reserved field of the TCP header is designated as the
ECN-Echo flag.

Bit 8 in the Reserved field of the TCP header is designated as the CWR
flag.

It would be great if Ethereal could decode and display ECN.  The Linux
kernel 2.4.0-test8 and up support and use ECN.

Dax Kelson
Guru Labs