| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a multicast delivery system in which the same data can be delivered to a large number of terminals while avoiding concentration of processing load due to acknowledgement processing or retransmission processing at a transmission server in a large scale system where the total number of terminals being delivered with multicast data is several thousands or several tens of thousand. SOLUTION: The multicast delivery system is arranged such that a terminal group having a plurality of terminals and a group server for managing the receiving condition of multicast data at each terminal is formed, each terminal in the terminal group transmits the acknowledgement information of multicast data to the group server, and the group server specifies the terminal receiving the acknowledgement information as a received terminal, specifies the terminal not receiving the acknowledgement information as a not yet received terminal and requests the received terminal to transfer the received multicast data.</p> |
