Patent ID: 8406222

Claim:
A control system of a communication network performing control to continue a communication with a communication terminal of an opposite side without interrupting said communication between communication terminals by switching at least one communication terminal performing said communication to a switch destination communication terminal not performing said communication, wherein the communication to be continued includes a session having a logical data transmission path between opposite side applications of said communication terminals, said control system comprising: a processor coupled to: a call control part operable to set a physical and logical transmission path between said communication terminals by performing a routing control of data packet transfer in a transport layer to control a call connection; a session management part operable to manage establishment of a session between the applications of said communication terminals; and a switching request processing unit operable to control said call control part and said session management part, wherein said switching request processing unit exercises functions of: receiving a session switching request signal from said at least one communication terminal, the session switching request signal including identification information identifying the switch destination communication terminal and session state information including states of applications on said at least one communication terminal; instructing and controlling said call control part to originate a call to and establish the call connection with said switch destination communication terminal based on the identification information and the session state information and to set a transmission path between said switch destination communication terminal and said communication terminal of the opposite side, and instructing and controlling said session management part to switch the session between applications on the communication terminals to a session between applications on said switch destination communication terminal and said communication terminal of the opposite side after establishment of said call connection by said call control part.