The shape of this usage pattern remains relatively constant throughout the academic year with only slight variation in the usage amplitude. Call Rejection During the hours of peak usage, customers receive a busy signal when all the trunks are filled. The Modem Usage vs. Time of Day chart also indicates the time of day that a customer is most likely to receive a busy signal. Call rejection may also be a function of modems refusing a call due to improper string commands, authentication, or frozen modems. Of the three, the frozen modem is the greatest cause for concern because this condition cannot be cleared until after the connection is dropped.
Frozen modems require a manual reset of the modem port.
On a particularly high usage day during Finals Week, approximately 22,000 calls were offered to the general use modem bank. A contention ratio is the ratio of the number of users per remote access port. Industry standards indicate that for satisfactory service in the general Internet community, the ratio of users per port should be between 10 and 12 to one. This is the current contention ratio after adding 480 modems to the pool through the Provost s Office funding allocation and the conversion of the RAMP pilot to full service. The average pilot user connected approximately three times daily with a session length of approximately 35 minutes.