Patent ID: 8327418

Claim:
A projector comprising: a communication connection establishing unit which establishes a communication connection with a plurality of terminals over a network, the plurality of terminals including a plurality of receiving terminals and a source terminal, the plurality of receiving terminals including a first receiving terminal having a token that grants the receiving terminal authority to control the source terminal over the network through the projector, the communication connection establishing unit receiving from the source terminal a presentation transmitted over the network to the projector; a lens through which the presentation is projected to display the presentation; a presentation data relay unit which receives presentation data of the presentation from the source terminal over the network, broadcasts a presentation image to the plurality of receiving terminals over the network so as to display the presentation image of the received presentation data on each of the plurality of receiving terminals, and, while broadcasting the presentation image to the plurality of receiving terminals, broadcasts voice information received from at least one terminal among the plurality of terminals to the plurality of terminals other than the at least one terminal so as to output, from each of the plurality of terminals other than the at least one terminal, the voice information input from the at least one terminal; a priority order determining unit which determines a priority order of the plurality of receiving terminals; and a presentation control unit which controls at least one of transmission and reception of the presentation image and the voice information, receives from a second receiving terminal and a third receiving terminal among the plurality of receiving terminals a request to control the source terminal, assigns the token to one of the second receiving terminal and the third receiving terminal having a highest priority among the second receiving terminal and the third receiving terminal requesting the token, receives from the one of the second receiving terminal and the third receiving terminal assigned the token a command to control the presentation transmitted by the source terminal, and transmits the command to the source terminal, wherein the source terminal receives the command from the presentation control unit, controls the presentation in accordance with the command, and transmits the controlled presentation to the communication connection establishing unit.