On Thu, 17 Nov 2011 11:32:27 -0500, wrote:

On Thu, 17 Nov 2011 05:41:40 -0600, "HeyBub"
wrote:



Bub, you must be young. The original modems were 300 BPS
As late as the 80s, the standard business modem was 1200 or 2400 BPS
and the 9600 BPS modem was leased line only.

I wish I was young. An actual federal regulation prohibited modems from
working at the speeds over (if I remember) 56K.

Even today, most modems operate at 2400 BPS. And there are millions of them.
(Think ATM machines).

The 56kb was not a federal regulation it was simply the limitation of
one channel of a T-1 line (actually 64kb) minus the overhead necessary
to move data on it. That limit still exists on a dial up line. You do
quite a bit better with ADSL but that is a different breed of cat and
the data is not moving through the switched network. It gets split out
before you get to the switching equipment.

No, there is/was an FCC regulation disallowing 56K (53K max for V.92). The
56K "limit" isn't T-1 speed (1.5Mb) limited, rather audio channel limited
(8kHz x 16b).

I have been away from the ATM business for 20 years but I would be
surprised if they are still running on SDLC lines. I would expect them
to be on the network with the rest of the bank system and going out in
their broad band traffic. I really don't know for sure tho. I just
threw away a couple of old bisync modems a while ago because I
couldn't get a bite on Ebay. I also had a 9600 BPS modem that was
either bisync or async. All of them could either be leased or dialup.

Depends on the ATM, I'm sure. The ATM at the QuickieMart (I'm sure the vast
majority of them) are dialup. At one time they were 1200bps, but they could
easily be 2400bps, now. The issue is connect speed, so the lines can be
turned around quickly.