| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a communication device, a communication system, a communication method, and a communication program that allow a communication device that has established a session with another communication device to reliably establish a session with a new communication device. <P>SOLUTION: A communication device 12 sends a request packet (INVITE) for requesting a session to be established with a communication device 13 (S12). The request packet stores offer information. The communication device 13 specifies media information used in the session with a communication device 14 as offer information and stores it with answer information in a positive response packet (OK response). The communication device 13 sends the positive response packet to the communication device 12 (S14). The communication device 12 sends an ACK packet storing the answer information to the communication device 13 (S16). A session is established between the communication devices 12 and 13 to carry out a TV conference (S18). <P>COPYRIGHT: (C)2012,JPO&INPIT |
