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View Full Version : Slower Modems, Faster Computers...



IBMMuseum
September 1st, 2006, 11:58 AM
Hello All,
The thread "Modem for XT Computer" brings up an interesting inverse: What are the conditions where a slower internal modem would be desired on a much more capable system? In my case it was microchannel PS/2s going up to Socket 5 "Classic" Pentiums (able to run Windows 95 or NT easily), but internal modems above 14.4Kbps not existing.
But when even some modern-day systems use lower baud rates because they don't need faster speed it becomes worthwhile to consider:

A paging system terminal
In my office we monitor equipment through the network. When a server goes down, the modem (really only on there for that purpose) dials a paging system to notify us. Paging equipment is typically run at 1200bps or below, where some newer modems can't step down to that rate quite so well.
I'm not suggesting something in modern office use where the systems are PCI only, but some mid-range concept to get the ideas flowing here...

A send/receive faxing system
FAX machines have never gone over 14,400bps. A fax/modem with that capability is easy to find. Put some flavor of DOS or Windows faxing software in place & you have it all set up. This is a situation where the modem isn't used where a faster connection isn't needed (just like the previous idea).

Remote console
Even though they have interfaces that can be used over a network, many routers/gateways have a local console port. Top speed there is usually 9600bps. It does take an external modem at the equipment end, but on the other side an internal modem on a mid-range system to dial in remotely. Security has to be considered, but that is at the equipment end.

Any others?

mbbrutman
September 1st, 2006, 12:52 PM
Is it an issue? Are there modems, modern or otherwise that can drop down to 300 or 1200 bps?

In the classic setup, the UART is on the machine and the modem is an external device. When the PC sets the speed it is setting the speed of it's UART, not anything in the modem.