MULTICAST RECEPTION TERMINAL AND MULTICAST RECEPTION METHOD, AND METHOD OF GRASPING MULTICAST GROUP

PROBLEM TO BE SOLVED: To solve the problem of an IP broadcast system having an upper limit in the number of IP broadcast channels to be simultaneously distributed to each home, in which a receiving terminal cannot receive a message and blackout occurs when the number of IP broadcast channels stored as a last channel exceeds the upper limit when the receiving terminal is started. SOLUTION: A reception request generation section of television transmits a Leave message to a multicast group corresponding to each channel (S101) immediately after start-up, thus inducing a Query message from a router, monitoring and receiving a membership report from each terminal (S102), and creating a multicast list being distributed to the home concerned (S103). When the number of multicasts being distributed has reached an upper limit, and no multicast address corresponding to the last channels are included in the multicast list, any of the multicasts being distributed is received instead (S105), thus preventing blackout. COPYRIGHT: (C)2011,JPO&INPIT