[Guy Harris <guy@xxxxxxxxxx>]

> I found the Quatech MPAP-200/300 RS422/485 PCMCIA card in a magazine ad.
> Not a hint of Linux support on their web page but looks like it would
> act as a high speed (up to 2.45 Mbit) serial port.  Coupled with a good
> laptop, this would make a beautiful portable analyzer.  I suppose the
> Kernel would have to be modified to work with the card's 1024 byte
> buffer. 
> 
> The protocol stack in the SONET bit stream in question is LAPD/CLNP/TP4.

Ethereal can dissect LAPD (although it doesn't hand LAPD packets to
CLNP, so you'd have to add support for that), can dissect CLNP, but
doesn't appear to have any TP4 dissection, just COTP dissection.

You'd also need some way of plugging the board into Ethereal's
packet-capture mechanism; unless you added code to Ethereal to read from
stuff other than just libpcap, you'd have to do a driver for the card
and plug it into the Linux socket mechanism to the extent that PF_PACKET
(or SOCK_PACKET) sockets would see the packets.