Wireshark-users: Re: [Wireshark-users] pcap filter for ingress egress selection

From: Sake Blok <sake@xxxxxxxxxx>
Date: Sat, 2 Jul 2011 10:00:44 +0200
On 24 jun 2011, at 11:10, Oguz Yilmaz wrote:

> Are there any pcap filter for selecting packets according to their
> direction. My solution was using "ether dst" or "ether src". hoıwever
> this depends on knowing MAC address of the interface. I want to ask
> whteter there is another way of selection of ingress and egresss
> packets seperately.

The pcap format does not provide means to store the direction of a packet (or the interface on which it was captured). So when using pcap files, you will have to filter by mac-addresses and/or IP addresses. This does however mean you have to know the topology of the network.

In pcap-ng, I think there is the possibility to store interface and direction information. But AFAIK this has not been implemented in Wireshark yet (pcap-ng support is slowly increasing in Wireshark).

Hope this helps,
Cheers,


Sake