>>From the ISP's perspective what's the practical difference between using
>PRI and CT1? It seems that ultimately CT1 will allow 24 B's and is
>certainly cheaper (and more widely available). I'm aware that the CT1
>code is in beta. But this question is really not Livingston-specific.
>(So why am I posting it here? Because its at least highly
>Livingston-relevant.)
Chris, the difference comes in the signalling. CT1 does allow 24 B's
but the price you pay for that is that each channel is only 56K (in-band
signalling robs the bits from within each channel rather than taking them
from a separate "D" channel). As a result, any analog calls taken over
them tend to connect about 4K-8K lower than PRI if you are using the newer
technologies that try to "push the envelope" so to speak. Current
28.8/33.6 modem users may not see a difference but it most likely will
make a difference for 56K/X2 etc. They may develop a CT1 that does not
use in-band signalling. But then it will still not necessarily be PRI.
The other difference is the "missing I", ie. No ISDN. Many ISP's like
the fact that they can support ISDN, 56K technology, and existing analog
modems all with the same phone number thus minimizing customer confusion.
The only other technology that currently can provide the same flexibility
is PRI's cousin, BRI which many ISP's can get at a much more reasonable
rate than either PRI or CT1.
Hope that helps.