DIGITAL BROADCASTING DATA DISTRIBUTION SYSTEM AND ITS METHOD

摘要

A packet loss in IP multicast is covered. In a digital broadcasting data distribution system for distributing digital broadcasting data from a distribution server to a plurality of receivers, the distribution server has an error detection symbol inserting means for inserting an error detection symbol for detecting a transmission error in each distribution packet or discontinuous errors in the distribution packets or both of them into the digital broadcasting data, a multicast means for multicasting the digital broadcasting data into which the error detection symbol is inserted to the receivers, and a unicast means for unicasting a distribution packet whose retransmission is requested by one receiver to the one receiver. Each of the receivers has an error detecting means for detecting the transmission error in each distribution packet or the discontinuous errors in the distribution packets, or both of them by using the error detection symbol and a retransmission request means for requesting the retransmission of the distribution packet in which any of the errors has been detected to the distribution server.