IP phone system, IP exchange, IP terminal, method of backup IP exchange, and how to log in IP terminal

摘要

PROBLEM TO BE SOLVED: To provide appropriate technologies, when three or more IP exchanges are to be multiplexed.;SOLUTION: Each of a plurality of IP exchanges 1 is assigned with a priority. Each of the IP exchanges 1 autonomously switches its operation mode so that the IP exchange 1, which has the highest priority in the operating IP exchanges 1 is operated in an operational system and the other IP exchanges 1 are operated in a waiting system. In addition, an IP terminal 2 logs in the IP exchange which has the highest priority in the operating IP exchanges 1 to receive IP telephone exchange services from the IP exchange 1.;COPYRIGHT: (C)2009,JPO&INPIT