Sorry Ed, Toslink and ST (AT&T) are not compatible. They are both "optical" in that they both use light as the transmission medium, but there the similarity ends. They use completely different transmit/receive devices. The Toslink device costs about $5, the ST costs about $150, on each end!
There are digital switching devices available. The only brand I know, which is now only available used and excellent, is the Wadia Digilink. But I'm sure there are others.
There are digital switching devices available. The only brand I know, which is now only available used and excellent, is the Wadia Digilink. But I'm sure there are others.