| 摘要 |
PROBLEM TO BE SOLVED: To avoid calls from a telephone number to be rejected after the concerned telephone number which had been used to make nuisance calls is cancelled or is stopped to be used to make the nuisance calls.SOLUTION: A management server, which is connected to a telephone or an adapter connected to the telephone via a network, continually updates, from an incoming call history, a reference time as a reference by which time of the latest incoming call is determined for each telephone number registered on a telephone number list used for determining whether an incoming call is a nuisance call or not, determines, from an elapsed time from the reference time, whether or not a predetermined time period has passed since the incoming call was made for each telephone number, and updates the telephone number list by removing the telephone number with no incoming call from a target to be determined as the nuisance call or changing so as to lower an evaluation point indicating a possibility of the nuisance call so that the possibility of being the nuisance call is reduced. By this configuration, the telephone number with no incoming call record for a predetermined time period is assumed that the concerned telephone number is possibly cancelled, allowing to be reflected in the determination of possibility of nuisance calls. |
