Switching method and apparatus having subscriber state management

Abstract

A switching system is provided in which when a calling subscriber has transmitted an identification (ID) number of a called subscriber and an ID number of the calling subscriber from a calling terminal to a switching equipment having a subscriber control table at the time of making a call, the switching equipment receives the ID numbers and connects the calling terminal with the called terminal. In response to an input of an ID number of a called subscriber and an ID number of a calling subscriber by the calling subscriber to a terminal at the time of making a call, the switching equipment changes a registration state corresponding to the ID number of the calling subscriber in the subscriber control table from an idle state to a busy state, manages the idle and busy states of the subscriber himself or herself corresponding to the ID number, retrieves the subscriber control table in response to a reception of a call signal which designates an ID number of a called signal from a calling subscriber, and forwards the call to a default terminal which has been registered in advance by the called subscriber having the ID number, when the terminal corresponding to the called subscriber having the ID number is busy and the called subscriber having the ID number himself or herself is not busy as a result of the retrieval of the subscriber control table.