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From: dheeraj@cs.umd.edu (Dheeraj Sanghi)
Newsgroups: comp.protocols.tcp-ip
Subject: Re: Duplicate packets in Internet
Message-ID: <24805@mimsy.umd.edu>
Date: 8 Jun 90 03:53:46 GMT
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Reply-To: dheeraj@cs.umd.edu (Dheeraj Sanghi)
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Organization: U of Maryland, Dept. of Computer Science, Coll. Pk., MD 20742
Lines: 37

>I wonder if people have noticed duplicate IP packets in
>any study. Is there any possibility of duplication apart
>from because of some bug in the gateway software?
>
>Any pointers in this regard would be much appreciated.
>
>Thanks,
>
>-dheeraj

I have received lots of replies to my query. I wish to thank all
of you. Because of large amount of mail I have received, I am sorry
I would not be able to reply to all of you personally.

Here is the summary of responses:

Many people suggested that there is some problem with NSS gateways
and they duplicate packets. It could be checked by pinging any of
the NSS gateways.

Many people suggested that duplicates are due to congestion, bad
timers etc at the transport level. Sorry, I was interested in
duplicates that the network generates, and not those which are
generated by the source transport level protocol.

Couple of people suggested that duplicates at the IP level could
be the result of link level retransmission.

Thanks once again to all of you,

-dheeraj

--
Dheeraj Sanghi			(h):301-794-6247	(o):301-454-1516
Internet: dheeraj@cs.umd.edu	UUCP: uunet!mimsy!dheeraj
	When you find you are on the side of the majority,
	it is time to reform.		- Mark Twain