Re: TCP checksum and device driver eri0

From: Martin Paul (
Date: 06/30/03

  • Next message: Casper Dik: "Re: TCP checksum and device driver eri0"
    Date: Mon, 30 Jun 2003 10:20:49 +0200 (MEST)

    > During a snoop session on a 280R with solaris 9 and network interface
    > eri0, I noticed that the TCP checksum field of every outgoing packet was
    > incorrect.
    > ...
    > The same packet snooped on the network has the correct checksum value.
    > I believe that something happens between the snoop point on the machine
    > and the network interface eri0 output.

    I guess that's the same effect that's described in the ethereal FAQ at:
    It's because the checksum is added to the packet by the network
    interface, and not by the TCP/IP stack.


                             Martin Paul | Systems Administrator
          Institute for Software Science |
    Liechtensteinstrasse 22, A-1090 Wien | Tel: 01 4277 38803
   | Fax: 01 4277 9388

  • Next message: Casper Dik: "Re: TCP checksum and device driver eri0"

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