Abstract: On the basis of a state of multicast packets which are transmitted among a plurality of terminals connected via a network, a terminal, which determines a receive order for maintaining an identical order of multicast packets to be received by the plurality of terminals, is selected. Upon transmitting a multicast packet from one of the plurality of terminals, the receive order informed from the selected terminal is appended to that multicast packet.

Abstract: On the basis of a state of multicast packets which are transmitted among a plurality of terminals connected via a network, a terminal, which determines a receive order for maintaining an identical order of multicast packets to be received by the plurality of terminals, is selected. Upon transmitting a multicast packet from one of the plurality of terminals, the receive order informed from the selected terminal is appended to that multicast packet.

Abstract: On the basis of a state of multicast packets which are transmitted among a plurality of terminals connected via a network, a terminal, which determines a receive order for maintaining an identical order of multicast packets to be received by the plurality of terminals, is selected. Upon transmitting a multicast packet from one of the plurality of terminals, the receive order informed from the selected terminal is appended to that multicast packet.

Abstract: In an electronic conference system, a speaker's equipment acquires information regarding the audience's equipment from the audience's equipment, produces presentation data for transmission suitable for the audience's equipment, by applying a prescribed processing to the presentation data according to the information regarding the audience's equipment, and transmits the presentation data for transmission to the audience's equipment, such that the presentation data can be displayed correctly even at the audience's equipments which have display capabilities different from that of the speaker's equipment.

Abstract: In the presentation system in which images are to be presented to audience during a presentation by a speaker according to image display commands issued by the speaker, a receiving side apparatus stores the image files received from a transmitting side apparatus operated by the speaker, monitors a state of storing the image files in the storage device, and changes at least a part of storing states of the image files stored in the storage device, when it is detected that storing of one image file that is currently received or scheduled to be received from the transmitting side apparatus is impossible, so as to make the storing of the one image file into the storing device possible.

Abstract: A communication control apparatus according to the present invention has receive means and own terminal identifier setting means. The receive means receives terminal ID information having information of one or more terminal identifiers transmitted from one or more terminals with which communication is being held. The own terminal identifier setting means sets a terminal identifier among a plurality of terminal identifiers which are other than the terminals of the other terminals obtained from all terminal ID information items received from the receive means, which have been previously set and which can be used for the communication.

Abstract: A plurality of terminals communicate. One terminal belongs to a plurality of groups of terminals. In the communication apparatus, a terminal information memory stores terminal identifiers. A sending section sends the communication information with the terminal identifiers of other terminals participating in one group to the other terminals. A receiving section receives information sent by the other terminal. A group discrimination section compares the received terminal identifiers with the stored terminal identifiers, and discriminates the group from which the received information was communicated according to the comparison.