| 摘要 |
Even when an SIP server imposes a restriction on a description content of an SDP, an image communication device can freely define a content of a media session with another end without receiving the restriction. Even when the image communication device is connected to a carrier network set for a purpose of only a usage of voice communication, the image communication device can carry out communication of image data or transmission of a character string. An image communication device establishes a media session by exchanging a message of a call control protocol with a communication device of another end and transmits image data. The image communication device describes information relating to the media session to be requested to the communication device of the other end or a character string to be transmitted to the communication device of the other end in a field not interfered by a call control server.
|
