COMMUNICATION DEVICE, COMMUNICATION METHOD, AND COMMUNICATION PROGRAM

摘要

PROBLEM TO BE SOLVED: To provide a communication device and the like for performing communication using an optimal band according to communication forms with various transmission destinations including NGN while enhancing connectivity.

SOLUTION: A communication device related to the present invention selects a first band from among plural candidate bands when a connection form is a first connection form of being connected to an IP network that uses SIP in session control and that has a charge amount different for each band range in which the IP network is used via a GW for the IP network, selects a second band that is the highest band in a band range with a charge amount different from that of the first band and that is a band lower than the first band from among the plural candidate bands when transmitting a first negotiation message in which the first band is declared and receiving an error response, and determines a communication band to be the second band when transmitting a second negotiation message in which the second band is declared and receiving a declaration acceptance message.

COPYRIGHT: (C)2012,JPO&INPIT