Patent ID: 8429262

Claim:
A communication system comprising: multiple communication terminals that are used by multiple users; a management unit that holds management information expressing which type of communication mode corresponding to which communication address information is used by which user and by which communication terminal, and connection information including communication address information of one communication terminal that has communicated and communication address information of another communication terminal that has communicated; a terminal location specification unit that specifies locations of communication terminals; and a user location specification unit that specifies locations of each of the users, wherein the management unit holds connection information corresponding to an instance of communication even if that instance of communication has ended; each of the multiple communication terminals communicates with other communication terminals in one or more types of communication modes, and includes a communication support unit; in the case where a first-type communication mode of a first communication terminal that includes the communication support unit is used by a first user, the communication support unit accesses the management unit to specify communication address information corresponding to the first-type communication mode in a second communication terminal used by a second user, and the first communication terminal communicates with the second communication terminal in the first-type communication mode using the specified communication address information; the first user is a user that used a second-type communication mode of a communication origin terminal prior to switching to the first-type communication mode of the first communication terminal; the second user is a user that communicated with the first user using the second-type communication mode of a communication destination terminal prior to switching to the first-type communication mode of the first communication terminal; and the specified communication address information is communication address information specified based on an instance of communication address information within the connection information that has another instance of communication address information corresponding to the second-type communication mode used by the first user, and based on the management information, and wherein in the case where information expressing that a user using the first communication terminal is the first user is not included in the management information, the first user is specified for the first communication terminal based on a location of the first communication terminal as specified by the terminal location specification unit and a location of each of the users as specified by the user location specification unit.