Both in US and In Japan, SONET/SDH systems are used to deliver such non-IP
traffic as CATV/Video over the same physical facilities as IP traffic.
Indeed, I can walk you into a top-rated commercial television station using
a large Unix box with six ATM-over-SONET interfaces to drive video
broadcast streams to the stations' live broadcast to millions of viewers.
The same interfaces also transport TCP-IP application control data between
Unix and the various off-line editing systems and the graphic development
engines (MAC/W'95).
You should not think that the prospect of internet based viewers are
outside the planning horizion of commercial broadcast industry, even if
that industry consists of predominately time critical (non-IP traffic)
today.
Some major players in this industry agree that the mixture of SONET/SDH
with both IP and ATM traffic is "really keen".
..mike..