Patent ID: 7933261
Filing Date: 2011-04-26
Classification: H04L,H04M

Abstract:
1. A communication method for performing data communication between a transmission-side communication device and a reception side communication device via a network according to a predetermined mode, the communication method comprising the steps of: at the transmission-side communication device, sending a data transmission request, according to a session initiation protocol, to the reception-side communication device for transmitting transmission data to the reception side communication device; at the reception-side communication device, sending a substitution notification to the transmission-side communication device according to the session initiation protocol in response to the data transmission request from the transmission-side communication device and before completion of reception of the transmission data; at the transmission-side communication device, making a first attempt to establish the data communication for transmitting the transmission data according to a first communication mode; at the transmission-side communication device, making a second attempt to establish the data communication according to a second communication mode for transmitting the transmission data when the first attempt has failed; and at the reception-side communication device, sending a reception completion response notification according to the session initiation protocol to the transmission-side communication device at the time of the completion of reception of the transmission data performed according to the first communication mode or the second communication mode.