Wireshark · Ethereal-users: Re: [Ethereal-users] question about fddi on ethernet inferface

[Guy Harris <gharris@xxxxxxxxx>]

Snyder, William T wrote:

> We have an fddi ring we are trying to analyze.
>
> We have a black box fiber splitter, fiber to ether net converter and a 
> pc with ethereal.
>
> We want to capture the traffic on the FDDI ring.  We know FDDI is 
> different then Ethernet packets.
>
> Is it possible to get ethereal capture for us?

If you can run Ethereal on one of the machines on the FDDI ring, or can 
get an FDDI adapter for the PC, you might be able to capture on that 
machine's FDDI interface.

I don't know what the "fiber to Ethernet converter" does, but it's 
probably a bridge or router.  As a bridge, FDDI frames bigger than the 
default 1514 or so byte standard Ethernet maximum might cause problems. 
 As a router, those frames would be fragmented, at least if they're 
frames for a fragmentable protocol (IPv4, IPv6) and don't have the 
"don't fragment" bit set).  Both of those are side-effects of not 
*directly* capturing on the FDDI ring, and might, or might not, cause 
problems.