When a user dials in, their analog signal is converted to digital and
travels to the ISP onto their channelized T1 (24 channels) into the PM3,
then connects to the digital modem. What is really cool is that 24
lines are combined into 1 physical line that plugs directly into the
box. Which eliminates any serial cables, extra wires, etc.. also the
digital lines are much better quality, which means your users should get
real 28.8, 33.6 connections rather than 21600 or 24000.
The problem with Channelized T1s? The bells! BellSouth charges
aproximately $1,000 for a channelized T1. Another company smack dab in
the middle of BellSouth territory (North State) was charging
aproximately $250 for a channelized T1 until their new tarrif allowed
them to charge $1,000. I am always interested in the phone companies
pricing as it directly affects the ISPs and internet users.
So, if you pay $1,000 for a channelized T1, your paying $41.67 per
phone line. This isn't too bad if analog phone lines are comparatively
priced. But around here analog lines are anywhere from $15 to $60. So
there is a trade off either in $cash$ or in busy signals or unhappy
customers.