| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To enable a client on receiving multicast content to continue to receive the content in a moving destination area, even if the client moves to another area during reception. <P>SOLUTION: While multicast-distributing the content to a first area, a multicast control apparatus for receiving the content from a content-distributing apparatus transmits a query message for causing the client in a state on receiving the content to return a reply message, to the first area. If the reply message is not returned, the multicast control apparatus transmits a query message to a second area, and when it receives a reply message to the query message, the multicast control apparatus starts multicast distribution of the content to the second area. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
