I am only aware of one widely utilized standard for optical transmission of
digital audio, usually referred to as the ADAT Optical Digital Interface
(also known as a "Lite Pipe" interface or simply an "Optical Digital
Interface"). I am not sure if it actually originated with the ADAT (it may
have simply popularized it), but it is supported as a standard for optically
networking digital audio by several manufacturers of audio equipment.
I am not sure of the exact specs, but this interface will carry at least 8
channels of uncompressed Red Book audio (44.1 kHz sample rate,
16-bits/sample). I believe it is capable of considerably more than this,
but I can't say for sure. I know it allows for the basic routing of
multiple audio channels through an optical network (you could do some
fantastic stuff with this in your house if you are an audiophile), but I
don't know of anyone who has tried this over a standard data network. Some
higher end consumer electronics have built in support for Lite Pipe
interfaces, or you can buy a converter box for systems that don't include
support.
More information is available at on the Alesis site at: http://www.alesis.com
Hope this helps.
-James Rogers
jamesr@best.com