jdominey@bsga05.attmail.com (06/21/91)
In V11#471 Jim Redelfs <ivgate!Jim.Redelfs@uunet.uu.net> writes: Mark Miller wrote: >> as I understand it, virtually all long distance calls are sent in a >> digital format. > I believe this is in error. Although AT&T is actively replacing the > analog facilities within their VAST system, I'm sure they have a LONG > way to go. > It wouldn't surprise me to find that only HALF of their traffic makes > the long haul digitally -- perhaps even less. Surprise! My figures are at least a year out of date, but AT&T's network digitization is almost complete. As of mid-1990, about 95% of the network was digital. Since digital circuits are given preference by the switches, the actual percent of calls carried digitally was closer to 98%. AT&T made an immense push starting in '87 or '88 to switch as much as possible from analog to digital facilities. This included a six billion dollar accounting write-down one year to dump some of the old stuff. It's been a remarkable shift, really. >> is this "fiber optic quality" spiel just some marketing drival > You can bet that it is actively persued my the marketing honchos, but > there is certainly a lot of truth to the implication that data > transmitted via optical fiber is usually of a higher quality than that > which is not. Not really. As someone already pointed out, once you go digital, the medium doesn't matter much any more. There's error correction built in to the process. If you're on a modem, the critical part of the data transmission path is the analog line between you and the local telco. Jack Dominey, AT&T Commercial Marketing, Tucker GA voice mail: 404-496-6925 AT&T Mail: !dominey or !bsga05!jdominey