eric@madhaus.utcs.utoronto.ca (Eric M. Carroll) (03/29/91)
On campus and in the Ontario Regonal Network we have had occasion to utilize Datapath modems from NT. These are circuit switched data modems that are of value when we cannot get leased line service to a locale. They are also cheaper for incity connections due to Canadian tariffs. We usually run them permanently nailed up. From time to time, the circuit falls over, and must be redialed. With the autoline feature, this part is not a problem. What is a problem, is that the modems are designed to require a DTE DTR transition before it will allow the call to succeed. While this is fine for terminals, it is lousy for Proteons, which expect a leased line, and not to have to toggle DTR. Does anyone know of a box that would provide V.35 interfaces and would auto-toggle the DTR when CD is lost or there is no activity on a line? The closest I have seen is a RS232 timeout box from Black Box. Any ideas? -- Eric Carroll University of Toronto Computing Services Network Development Support
lstowell@pyrnova.pyramid.com (Lon Stowell) (03/29/91)
In article <1991Mar28.201053.20100@gpu.utcs.utoronto.ca> eric@madhaus.utcs.utoronto.ca (Eric M. Carroll) writes: > >Does anyone know of a box that would provide V.35 interfaces >and would auto-toggle the DTR when CD is lost or there is no >activity on a line? The closest I have seen is a RS232 timeout >box from Black Box. > If you can't find one, just hack up the RS-232 box and use it. You'll need two V.35 connectors, then strip off the DTR and CD signals from these, pass them through the 232 box. Just bypass the clock and data leads around the 232 box...the rest of the V.35 signals are 232 compatible.
stigall@silver.ucs.indiana.edu (john stigall) (03/29/91)
I'm in the same situation that you are, Datapaths being the cheapest
solution for short haul 56K from our campus switch. If you notice the
characterics of the Automatic Line feature, you see several scenarios.
1. Power failure to the Datapath. This is OK, re-dialing happens fine.
(Switch set for DTR ON.)
2. Manual release of line - does not re-dial without toggle of DTR.
(Not so good.)
3. Any other loss of connection - You're out of luck, fella.
Anyway, Here's what my "Phone man" had to say about this recently:
I'M GLAD TO HEAR THAT THE DATAPATHS ARE PROVING RELIABLE. I WENT AHEAD
AND PUT THAT AUTOMATIC LINE FEATURE OF THE OTHER LINE. BY THE WAY,
IN BCS31 9( THE NEW SOFTWARE LOAD DUE IN MAY) THERE IS A FEATURE CALLED
CRITICAL PATH RESTORATION. WITH THIS FEATURE ACTIVATED ON A DATAPATH
LINE, THE SWITCH WILL SCAN THE LINE EVERY 5 MINUTES TO SEE THAT IT IS
CONNECTED, AND IF IT IS NOT, IT WILL REESTABLISH THE CONNECTION.
Looks promising, Eh? I'd call Northern Telecomm about this. It was
a feature requested by Indiana Bell. Any more questions?
--
John Stigall - Indiana University Computing Services Network
750 N. State Rd. 46 Bypass, Bloomington, Indiana 47405
(812)855-9255 stigall@ucs.indiana.eduroot@zswamp.fidonet.org (Geoffrey Welsh) (03/30/91)
Eric M. Carroll (eric@madhaus.utcs.utoronto.ca ) wrote: >From: eric@madhaus.utcs.utoronto.ca >Organization: UTCS, Network Development >Does anyone know of a box that would provide V.35 interfaces >and would auto-toggle the DTR when CD is lost or there is no >activity on a line? The closest I have seen is a RS232 >timeout box from Black Box. Surely someone at the U of T could wire up a 555 circuit that drops DTR for a second or five whenever a true -> false transition is detected on DCD?!? Such a thing would cost only a few bucks a box (hardly worth the parking, let alone the gas, for me to come out & build some for you!) -- UUCP: watmath!xenitec!zswamp!root | 602-66 Mooregate Crescent Internet: root@zswamp.fidonet.org | Kitchener, Ontario FidoNet: SYSOP, 1:221/171 | N2M 5E6 CANADA Data: (519) 742-8939 | (519) 741-9553 The mile is traversed not by a single leap, but by a procession of coherent steps; those who insist on making the trip in a single element will be failing long after you and I have discovered new worlds. - me