Method of changing the function of a telephone apparatus, a customer center for carrying out the method, and an user system including the telephone apparatus, and a method of changing the number of telephone lines, a customer center for carrying out the method, and an user system including the telephone apparatus, and a method of changing the function of a terminal, a customer center for carrying out the method, and an user system including the terminal

摘要

To add new functions to key telephone apparatuses, the user PC in the user system transmits a function add request to the customer center. The function add request includes information on the functions to be added and the telephone numbers of the key telephone apparatuses. Then, the customer center accesses the user's key telephone apparatuses via a public network on the basis of the received telephone numbers, acquires function information about the key telephone apparatuses, and determines whether the functions can be added, on the basis of the function information. Then, if the functions can be added, the customer center sends license codes for the functions to be added to the user's key telephone apparatuses via the public network, thereby additionally setting the functions.