falcone@erlang.DEC (Joe Falcone, HLO2-3/N03, dtn 225-6059) (10/01/84)
CC: The issue which bothered me the most of the three I posted was the one dealing with charges for data transmission over phone lines. Apparently, just for modems to work correctly, the central office has to sense when a carrier is on the line and do something special to make sure it isn't inadvertently clipped or interrupted during the data conversation. So there is technology available to detect when someone is using a modem on a telephone line, and presumably this technology could be connected to the time & charges apparatus in the central office. The result would be that if you use your line for voice, one set of charges apply, and if you use it for data, another set might apply. This mechanism is rather crude though since I does not keep track of the amount of bits being communicated. The new all-digital telephone systems will do this and charge by the bit for use of a special digital data channel paired with a quality voice line (which is fairer for us slow terminal hackers). Some of this stuff is going into medium-scale testing soon. (There was an article about a large experimental Japanese digital telephone system in IEEE Spectrum a few months ago. There was another article about internation datacomm wars more recently.) Since I know there are hundreds of telecomm engineers outs there, I sincerely invite corrections and further enlightenment. I was very disappointed that I did not get a single response on this particular issue. Please don't leave me disappointed any longer! (I don't read any of the comm newsgroups anymore, so followup or direct reply will have to do.) Joe Falcone Eastern Research Laboratory decwrl! Digital Equipment Corporation decvax!deccra!jrf Hudson, Massachusetts tardis!