Yeah, I somehow ended up being responsible for the college campus modem bank a bit before I got my home ISDN setup; a pair of livingston portmasters and a pair of T1s that connected them to the phone co.
One of the hardest / most confusing problems I ever had was with that stuff -- TPC gave me 2 hunt groups (one for faculty/staff the other for students). One worked fine the other just wouldn't work at all. Eventually (after turning off the "broken" one and still getting a login/PPP prompt when dialing I called TPC and asked "hey -- your docs have these 2 hunt groups -- are you _sure_ they're right?" and they'd actually given me another org's phone number for one of them and that other org also had a livingston portmaster on it. Sigh.
SDLC phone network stuff is fascinating -- "why is it all on one clock?" (synchronous data link control) -- because when it was invented it was absurd to presume you could get enough ram to buffer things for packets (ha! What's a packet?) -- it all just happens at all at once everywhere.
Another time someone dropped a backhoe on the cable trunks between the campus phone bunker and the campus; I glanced over and saw the techs patiently stitching back together the eleventy billion cable pairs between the switch and each phone on campus. 30 tons of copper later got replaced by 500 pounds of memory...
One of the hardest / most confusing problems I ever had was with that stuff -- TPC gave me 2 hunt groups (one for faculty/staff the other for students). One worked fine the other just wouldn't work at all. Eventually (after turning off the "broken" one and still getting a login/PPP prompt when dialing I called TPC and asked "hey -- your docs have these 2 hunt groups -- are you _sure_ they're right?" and they'd actually given me another org's phone number for one of them and that other org also had a livingston portmaster on it. Sigh.
SDLC phone network stuff is fascinating -- "why is it all on one clock?" (synchronous data link control) -- because when it was invented it was absurd to presume you could get enough ram to buffer things for packets (ha! What's a packet?) -- it all just happens at all at once everywhere.
Another time someone dropped a backhoe on the cable trunks between the campus phone bunker and the campus; I glanced over and saw the techs patiently stitching back together the eleventy billion cable pairs between the switch and each phone on campus. 30 tons of copper later got replaced by 500 pounds of memory...
Ayhow, grandpa DELNI needs a nap...