kuma kk wrote: > > hello group, > > I am facing a slow response issue on the network, have > captured the packet > with etherreal and found that the IP header for the data > orignated from the > source hosts have Header checksum as incorrect. > Noticed this error for all the TCPsegments > > E.g : Header Checksum: 0xd7f1 (incorrect, should be 0x1251) > Header checksum: 0x0000 (incorrect, should be 0x1a78) > > However the data received as response from the remote hosts > does not show > any checksum error
If the IP header really has an incorrect checksum, it would be dropped at the first device that deals with IP. It sounds like you're sniffing on the source side and Ethereal thinks that the source is setting the checksum incorrectly. The first router would drop this packet. The fact that you're seeing a response from the remote host means that the packet didn't get dropped, though. Unless what you're really seeing is a retransmission from the host and then a response from the remote host. Check for lots of retransmissions. That is what you would see if there was really a problem with the checksum. I would suspect that Ethereal got confused. Just to be safe, though consider what could be mucking with the checksum. For example, a NAT gateway needs to change it since it changes the IP addresses. Could it be confusing matters? Priscilla > > Don't know this is how it will work or is there any problem in > my network. > > Would appreicate any help ? > > TIA, > Kum > > _________________________________________________________________ > Chill out. Win a Himalayan holiday! > http://server1.msn.co.in/sp03/summerfun/index.asp > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=71545&t=71533 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
