| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a SIP proxy server which notifies alternative address information to a calling side automatically when a SIP message addressed to a SIP communication equipment in the network area within its jurisdiction is received from outside of the network area and the above-mentioned SIP communication equipment cannot establish the data communications by SIP. <P>SOLUTION: The SIP proxy server has a means for judging whether a SIP communication equipment 4 in LAN2 within its jurisdiction is in the state where new SIP communication is establishable; a table T for memorizing alternative address information in relation to the SIP communication equipment 4 in LAN2; and a means for describing in a redirection message the alternative address information M1 related with the SIP communication equipment 4 concerned and answering the calling side 30 (T12), when it is judged with the SIP communication equipment 4 as in the state where new SIP communication is not establishable while receiving INVITE addressed to the SIP communication equipment 4 from outside of the network area 2 (T11). <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
