PRIVATE BRANCH EXCHANGE HAVING ABSENCE SETTING FUNCTION

摘要

PROBLEM TO BE SOLVED: To make it possible to easily change the absence setting of an extension telephone set without an external telephone set operator performing a special operation and regardless of the type of a line on a private branch exchange side. SOLUTION: The extension number of a user of an extension telephone system, caller number notification information notified from a public network L and a relating table in which the relationship of the presence of absence setting is defined are preliminarily stored in the memory 10c of the private branch exchange 10 by using the caller number notification information (number display service) of the public network. When an incoming call comes from the network L, a main controlling part 10b refers to the relating information of the memory 10c and performs setting change of an extension telephone set system coinciding with notified caller number notification information so as to correspond to the presence of absence setting.