| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To maintain continuity of a session between communication apparatuses even after systems of relay apparatuses are switched, in a communication system where the relay apparatuses each for relaying a packet flowing between communication apparatuses of different communication conditions are made redundant. <P>SOLUTION: A communication system includs a relay system having a plurality of relay apparatuses each for relaying a packet flowing between a first communication apparatus and a second communication apparatus. The relay apparatus of an active system has a unit for acquiring continuity information about continuity of packet of a communication session between the first communication apparatus and the second communication apparatus, a unit for converting the packet of the communication session utilizing the continuity information and for transmitting the packet to a destination; and a unit for giving notification information including the calculated continuity information to the relay apparatus of a standby system. The relay apparatus of the standby system then has a unit for receiving the notification information from the relay apparatus of the active system and holding the notification information, and a unit for converting the packet of the communication session utilizing the held notification information and for transmitting the packet to the destination. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
