Abstract: A technique for performing message communications while assigning a space and respective time periods or time points at present, in past and in future is disclosed. A space-time object intercepts a message. Alternatively, this object per se executes the processing for immediately transmitting a message to a target object under management with relevancy thereto, for retaining the message by a future time point assigned, or for preparing and sending a message for searching logs in the past, thereby to realize the space-time communications.

Abstract: A presence management apparatus connected to first and second apparatuses via a network includes a unit for updating a first user's presence received from the first apparatus and a second user's presence received from the second apparatus, wherein the first user uses the first apparatus and the second user uses the second apparatus; a unit for registering a matching condition for another user's presence received from the first apparatus and designated by the first user and a matching condition for another user's presence received from the second apparatus and designated by the second user; and a unit for deciding if the first and second user's presences match the designated conditions when registration processing and/or update processing is performed.

Abstract: A multimedia communication system having at least one terminals capable of multimedia communication, a user information storage for storing the information on the users of the terminals, a terminal information storage for storing the information on the terminals and a media information storage for storing the occupied/unoccupied status of one or more communication media capable of being used at the terminals, wherein the occupied/unoccupied status of all the communication media for a designated user are read from the media information storage, the dynamic situation of the user is read from the user information storage, and the occupied/unoccupied status thus read is changed in accordance with one or more rules including the conditions for the dynamic situation and the contents of change in the occupied/unoccupied status.

Abstract: A presence management apparatus connected to first and second apparatuses via a network includes a unit for updating a first user's presence received from the first apparatus and a second user's presence received from the second apparatus, wherein the first user uses the first apparatus and the second user uses the second apparatus; a unit for registering a matching condition for another user's presence received from the first apparatus and designated by the first user and a matching condition for another user's presence received from the second apparatus and designated by the second user; and a unit for deciding if the first and second user's presences match the designated conditions when registration processing and/or update processing is performed.

Abstract: The conventional multi-user audio communication system and an IM system each require a server for managing a conference or a terminal having functions of the server. Thus, an environment without a server cannot be implemented. A specific terminal broadcasts an online or offline command for indicating an online or offline state with respect to an ad hoc network to all other terminals. In an online state, resources such as buffers used by a plurality of channels consenting in advance are allocated, a participation-expressing command including a number of a channel, which the terminal itself desires to participate in, is multicasted to a pre-assigned address, and audio as well as IM data is transmitted to the address at the same time. If other terminals are participating in the channel, a plurality of pieces of audio and IM data is received from the other terminals. In the case of audio data, a plurality of pieces of audio data are mixed and the mixed data is reproduced.

Abstract: A multimedia communication system having at least one terminals capable of multimedia communication, a user information storage for storing the information on the users of the terminals, a terminal information storage for storing the information on the terminals and a media information storage for storing the occupied/unoccupied status of one or more communication media capable of being used at the terminals, wherein the occupied/unoccupied status of all the communication media for a designated user are read from the media information storage, the dynamic situation of the user is read from the user information storage, and the occupied/unoccupied status thus read is changed in accordance with one or more rules including the conditions for the dynamic situation and the contents of change in the occupied/unoccupied status.

Abstract: The voice mail system includes a voice mail exchanger and a mail server. A voice mail communication between a telephone and a terminal device, such as a client computer, is registered in a LAN based multi-media mail box. A PBX based voice mail apparatus and a LAN based multi-media mail system are integrated such that voice information can be commonly used and reused.

Abstract: A data transmission method and system of a token passing type capable of periodically transmitting cyclic data produced in a station to other stations while enabling a packet data communication with high efficiency and without disturbing the periodicity of the cyclic communication. A token circulation time is set to be shorter than a cycle time for production of the cyclic data where no packet data to be transmitted. Also each station will pass an acquired token immediately to the next station if the station has no data to be transmitted. Thus, at least one station can have a token at least two times during the cycle time to transmit the cyclic data and the packet data. Upper limits may be set to capacities of the cyclic data and the packet data which are capable of being transmitted each time the token is acquired.

Abstract: A read/write replica of a file in a file server is updated through a communication line by a client. At the same time, a replica server detects the update data by using a virtual communication line between the client and a read-only replica of the file. The update data are used for refreshing the read-only replica. The refreshing process makes it unnecessary to send the update data from the file server to the replica server. Also, communication is made between the file server and the replica server to confirm validity of the update information taken in by the replica server to maintain equality of the files of the file server and the replica server. This can efficiently refresh the read-only replica of the replica server in a distributed data processing system without re-sending the update data.

Abstract: A data transmission method and system of a token passing type capable of periodically transmitting cyclic data produced in a station to other stations while enabling a packet data communication with high efficiency and without disturbing the periodicity of the cyclic communication. A token circulation time is set to be shorter than a cycle time for production of the cyclic data where no packet data is to be transmitted. Also each station will pass an acquired token immediately to the next station if the station has no data to be transmitted. Thus, at least one station can receives a token at least two times during the cycle time to transmit the cyclic data and the packet data. Upper limits may be set to capacities of the cyclic data and the packet data which are capable of being transmitted each time the token is acquired.

Abstract: A bridge apparatus for interconnecting networks in which at least two networks including a plurality of stations are connected, and which, when a transmission frame including an identifier of one station and an identifier of another station of a destination is received from the one station, forwards the transmission frame to a network to which the another station belongs based on the identifier of another station. A processor of the bridge apparatus for interconnecting networks performs delivery control of the transmission frame using an information which has been read out of an address check circuit for identifying the network to which the another station belongs with the identifier of the another station which is included in the transmission frame.