February 16, 1999
NDSU has its own local telephone private branch exchange (PBX) that presently serves
for a total of 4377 local lines. The University owns the local exchange (the 231 prefix), so it could support up to 10,000 campus telephone numbers. The Call Management System of the PBX has a lot of capabilities relative to being able to gather statistics on various kinds of use and relative to line control. Because of the complexities of maintaining a system of this size, NDSU employs an outside consultant for specialized engineering of the Call Management System.
To cover its cost of operation, the NDSU telephone system operates on a "charge back" basis. Long distance calls are charged from $0.10 to $0.25 per minute depending upon time of day, day, and destination. Phones connected to the NDSU switch have to get their long distance service through NDSU. NDSU is the only "carrier" permitted to provide service to all buildings on campus (including the residence halls and the university apartments). Campus phone lines are billed $15.00 per month for being connected to the switch. Installation and other phone repair service is billed at $30.00 per hour.
There are a few (less than two dozen) telephones on campus that do not connect through the campus PBX but instead connect directly to US West's local switch. These are primarily emergency phones.
The connection from the campus switch to off campus is via a number of T1 lines, where each T1 provides for 23 connections. Besides connections to long distance carriers, the local incoming and outgoing ISDN trunking (over the T1 lines) to/from campus gives
If all of the modem pool is in full use (presently there are 149 modem lines) and all the calls come from local off-campus sources, 72% of NDSU's local incoming connection capacity is in use. (Statistics collected recently indicate that between 7 and 8% of the modem pool calls come from on-campus; that is, they do not use the T1 lines. Although there is no further breakdown on the source of those campus calls, it is likely that most of them are coming from the university apartments.)