Dual communication system, cellular communication terminal and dual communication method therefor

Abstract

A dual communication system comprises a cellular communication terminal 1 having a plurality of communication means. The cellular communication terminal 1 is provided with a function to register the telephone number of WLAN communication means 12 to cellular phone switching network 100 and a function to register the telephone number of cellular phone communication means 11 to IP telephone switching network 200. When it is impossible to communicate with the cellular phone communication means 11 of the cellular communication terminal 1, the cellular phone switching network 100 automatically transfers any receiving call to the previously registered telephone number of the WLAN communication means 12. On the other hand, when it is impossible to communicate with the WLAN communication means 12 of the cellular communication terminal 1, the IP telephone switching network 200 automatically transfers any receiving call to the previously registered telephone number of the cellular phone communication means 11.

Dependencies are inferred from the claim text.