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New Member

duplicate ACK

What could be the cause of a duplicate ACK besides mismatched duplex and speed settings?

New Member

Re: duplicate ACK

dropped packets for one thing...not just mismatched settings...can be caused by excessive traffic, physical errors, bad drivers, bad nics....

where and how are you seeing them?

New Member

Re: duplicate ACK

I am not sure where my boss was seeing them but you can see the dropped packets when you ping. What kind of physical cable problems could there be? Mainly bad cables?


Re: duplicate ACK

dropped pings can be cause by a lot of different problems, physical line issues only being a small part of them. Check the speed/duplex of the interfaces between the host doing the pinging and the host receiving the ping. Check for errors. Check cpu utilization on routers, swtich and the hosts. Check buffer size and queue size. You could have anything from a router with 100% cpu to a interface queue thats full or even if the end host is over utilized and not responding in time.


Super Bronze

Re: duplicate ACK

Packets delivered out of sequence will also generate dup ACKs.