To handle 56K the central site MUST have a digital carrier. This is
primarily going to be PRI and Channelized-T1 lines connected to units
like the PM-3 or Ascend MAX. However, a BRI line would seem to allow
for the digital channel needed.
If your USR externals will accept a BRI line (I don't think they will, but..)
then you can use them to terminate the call.
But chances are you'll either need to pick up something like the Courier
I-modem to handle BRI lines - and I'm not sure that will terminate 56K.
You'd probably be better off going with a new unit that handles PRI or
channelized T1 - like a PM-3.
This isn't just us - ANY serial comm server will have this issue. 56K
MUST be terminated on a digital line. So ISPs are either going to have
to replace their analog modems with digital modems and replace POTS with
BRI, or they'll have to buy new comm servers and get PRI or channelized T1
to feed them.
The latter is likely to be less expensive for most. And you can still use
the older equipment for POTS users. It is expected that most users will
not upgrade to 56K since most modems out right now can't be upgraded - they
need to be replaced. AND the user needs to have a clean line and a fully
digital path through the phone company to use it.
If you are looking at the PM-3 for 56K start telling your users not to
buy USR X2 units, but to wait for Rockwell or - better - Lucent modems.
Lucent is claiming 45K uplinks, the others are 33.6K uplinks. So tell
them the wait may gt higher speeds. And since we're going with Lucent
if they have Lucent there should be no problems. Rockwell modems should
also work with us. But right now USR X2 will *not* work with the Lucent
system.
Eventually the ITU-T will produce a standard and we'll support that.
-MZ
-- Livingston Enterprises - Chair, Department of Interstitial Affairs Phone: 800-458-9966 510-426-0770 FAX: 510-426-8951 megazone@livingston.com For support requests: support@livingston.com <http://www.livingston.com/> Snail mail: 4464 Willow Road, Pleasanton, CA 94588