FYI,
I am trying to open a Unix snoop on the Ehtereal, from a Sun Sparc 9 box...
On Tue, 03 Feb 2004 Guy Harris wrote :
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>On Feb 2, 2004, at 8:28 PM, Jonty Ray wrote:
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>> Have Ethereal 0.10.1 and The h225 setup msg appears as unreassembled packet ( incorrect TCP check sum )
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>You're probably capturing traffic being sent by the machine running Ethereal, and the machine probably has a network interface that does checksum offloading. Packets sent on an interface that does checksum offloading, when they're captured by the machine sending the packet, don't have a valid checksum - the host hasn't given the packet a checksum, as it's letting the network interface do that.
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>Select "Preferences" from the "Edit" menu, open up the "Protocols" list, select "TCP", turn off the "Check the validity of the TCP checksum when possible" option, and click "OK" (click "Save" before you click "OK" if you want this to be your default setting).
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>That causes Ethereal not to check whether the TCP checksum is valid on a packet, so that it'll be willing to reassemble higher-level packets across TCP segment boundaries even if the checksum appears to be bad.
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>> All other msgs like call proceeding and alerting appear fine.
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>Those messages are probably small enough that they don't cross TCP segment boundaries.
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