Wireshark-users: Re: [Wireshark-users] Display Filter - Byte Offset Notation

From: Stephen Fisher <stephentfisher@xxxxxxxxx>
Date: Wed, 23 Aug 2006 20:50:19 -0700
On Wed, Aug 23, 2006 at 03:01:41PM -0500, Prigge Scott wrote:

> Using version 0.99.2, and am struggling to create a simple display 
> filter using byte offset notation. I want to simply capture traffic 
> where the first two bytes of the source address are 68.154. Shouldn't 
> this filter be as simple as ip[12:2]==68 154? I've tried lots of 
> different permutations, but can't get any to work. I have created the 
> same offset filter in another product, Network Instruments Observer, 
> and I get the results I would expect.

I don't think that Wireshark supports that format.  Do you want to match 
packets with source IP addresses in the 68.154.x.x range?  If so, 
"ip.src ==" will do that (or ip.addr to match either the 
source or destination).