| 摘要 |
A relay device for multicast communications. The relay device transmitting a user data packet, containing a content, in which to set a multicast address associated with the content, to a plurality of base stations belonging to a same zone in order to wirelessly transmit the content substantially simultaneously from the plurality of base stations, comprises a storing unit storing information indicative of a multicast group in which the mobile terminal participates together with information about the zone to which the base station performing wireless communications with the mobile terminal belongs, and generates a query packet for checking if the mobile terminal continues to participate in the multicast group stored therein, and transmits the user data packet containing the query packet to each of the base stations belonging to the same zone. |
