| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To solve the problem that transfer efficiency is improved in header compression, code conversion, etc. in communication on a transmission line with a limited transmission band, while, when a new call is connected and used while a plurality of calls are communicated, if a full-header packet is delivered, packets of the other calls are discarded or delayed. <P>SOLUTION: Information acquired by an SIP packet monitor is omitted from a packet header for transmission, and then packet type information by both internal coding method and external coding method is added to create a short header. Coded voice data obtained by coding the voice data of the packet for transmission and the short header are assembled into a packet and are delivered to a device at the other end. Then, based on the packet information contained in a packet received from the device at the other end, the speech data code-converted by a reception-side code converting means and a packet header which is the short header in the received packet decoded by a packet header decoding means based on the information from the SIP packet monitor are assembled into a packet and are delivered to a telephone device. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
