Subject: Re: ICMP handling for a fragmented packet.
To: Rohit Dhawan <>
From: Charles M. Hannum <>
List: tech-net
Date: 03/18/2001 22:15:52
On Mon, Mar 19, 2001 at 10:57:34AM +0530, Rohit Dhawan wrote:
>     Consider a packet, which gets fragmented while traversing through the network, such that the Fragment One has the higher layer header (say TCP header, with associated port numbers etc.). Lets us consider a case when  (say) fragment Seven's TTL becomes zero & an ICMP message is sent back to the Message Source. At the source, there is no way of identifying the port number of the originator of the message. 
>     In such a scenario, could you explain how would the Source handle the packet?

You're thinking too hard.  ICMP TIME EXCEEDED is basically ignored by
a host, so the presence or absence of connection information in the
packet is irrelevant.

> NB: I donot belong to your mailing list. I'll like to join it - if you think that is possible.

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