Re: DNS packet analysis.

Hi V.Jay,

There is nothing malicious happening here.

Each DNS response comes in two legitimate-looking fragments, for a total of 1480+575=2055 bytes. By "legitimate looking", I mean that the first fragment is always at offset 0 and of 1480bytes, and the second starts at offset 1480. Nothing untowards here.

It shows that the MTU of at least part of the path between DNS.server.com and outside.guy.com is 1480 bytes. I understand that this is the default MTU for Win/XP using PPPoE.

Hope this helps.

Regards,

Mark

---
Mark Cooper
SANS GCIA


----- Original Message -----
From: "larosa, vjay" 
To: 
Sent: Wednesday, December 11, 2002 8:37 PM
Subject: DNS packet analysis.

> Hello,


familiar

> with snort

Do you need help?

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