| 摘要 |
<P>PROBLEM TO BE SOLVED: To efficiently and highly reliably distribute data to a number of users. <P>SOLUTION: A transmitter 1 transmits data via a broadcasting link 2 consisting of a satellite link, for example. Receivers 3<SB>1</SB>-3<SB>5</SB>receive the data, and verify whether to have successfully received the data. Only when having failed to successfully receive the data, any of the receiver 3<SB>2</SB>, 3<SB>3</SB>and 3<SB>5</SB>, which can transmit information to the transmitter 1, transmit a NAK (negative acknowledgement) that is the request retransmitting the data via a communication link 4 consisting of the Internet, for example. When the NAKs are transmitted, the transmitter 1 only receives the NAKs and summarizes them. The transmitter 1 transmits the data for the NAKs based on the results of the summarizing via the broadcasting link 2, then the receivers 3<SB>1</SB>-3<SB>5</SB>receive them. <P>COPYRIGHT: (C)2007,JPO&INPIT |
