RE: [NAT] TCP checksum adjustment in NAT
"Kjeld Borch Egevang" <kjeld@egevang.dk> Sat, 01 September 2001 20:59 UTC
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From: Kjeld Borch Egevang <kjeld@egevang.dk>
To: Kavleen Bhatia <kavleenk@delhi.tcs.co.in>, nat@ietf.org
Subject: RE: [NAT] TCP checksum adjustment in NAT
Date: Sat, 01 Sep 2001 22:51:19 +0200
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Hi Kavleen. If your TCP checksum is bad, it might be because you forgot to include the pseudo header in the checksum calcalution. I can recommend, that you adjust the TCP checksum incrementelly (based on old address/port and new address/port). This will ensure that if the checksum was bad due to a transmission error in the path it will still be bad. Try to dump that packet, and calculate the TCP checksum by hand before and after NAT. /Kjeld -----Original Message----- From: nat-admin@ietf.org [mailto:nat-admin@ietf.org]On Behalf Of Kavleen Bhatia Sent: 29. august 2001 13:56 To: nat@ietf.org Subject: [NAT] TCP checksum adjustment in NAT Hi, I am currently implementing NAT on VxWorks. I am not able to calculate the adjustment to the TCP Checksum. The packet is not received at the destination due to bad checksum. could anybody provide any pointers to the same. Kavleen
- [NAT] TCP checksum adjustment in NAT Kavleen Bhatia
- Re: [NAT] TCP checksum adjustment in NAT Pyda Srisuresh
- RE: [NAT] TCP checksum adjustment in NAT Kjeld Borch Egevang