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Altera_Forum
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14 years ago

InterNiche stack drops packets when ip_chksum field is set to 0xFFFF

For our embedded products we use the iNiche stack. We have several systems running and we see occasionally network packets being dropped by the iNiche stack. We have the impression that it is somehow...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

Hmmm I just read the thread http://www.ietf.org/mail-archive/web/ietf/current/msg21280.html

The general view is that both 0x0000 and 0xffff are valid (and equivalent) for IP header checksums. Most code that generates them will not generate 0xffff.

The InterNiche stack should just remove all the code that zaps the checksum, and just sum the entire header and verify the result is 0xffff.

Note that 0xffff is special for the UDP checksum => not computed.