Ethereal-users: [Ethereal-users] Re: capture filter

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From: Phil Reinemann <Phil.Reinemann@xxxxxxxx>
Date: Wed, 18 Feb 2004 17:31:49 -0600
>> use colons, even though Ethereal documentation shows MACs with periods.

>Guy Harris: To which Ethereal documentation *on capture filters* are you 
referring?

The one you get from Ethereal (V0.10.0) Help->Contents, Capture Filters 
tab:
...
Some common examples:
---------------------
Example Ethernet: capture all traffic to and from the Ethernet address 
08.00.08.15.ca.fe

ether 08.00.08.15.ca.fe
... <end of excerpt>

(I'm assuming that "Ethernet address" is the MAC address.)

>       represented in hex digits.  The hex digits may be
>       separated by colons, periods, or hyphens:

>           fddi.dst eq ff:ff:ff:ff:ff:ff
>           ipx.srcnode == 0.0.0.0.0.1
>           eth.src == aa-aa-aa-aa-aa-aa

Yeah, I see that (in the Ethereal.com man page), not sure how I missed that 
before. Maybe I didn't look hard enough.

I can't see what I might have been looking at for tcpdump that lead me to 
believe periods were used for the MAC. Today, I didn't see anything in 
http://www.tcpdump.org/tcpdump_man.html that specifies colons, periods or 
anything for the MAC. Maybe I was looking at something within Ethereal.com 
that showed tcpdump (instead of providing a URL), but I can't find it now.

My major intent was to help others who may have capture filter problems, 
and who looked at the Ethereal on-line (within the program) help for info 
about capture filters, and assumed periods were OK and that "ether" without 
"host" was OK.

	Phil