Patent ID: 6781979
Filing Date: 2004-08-24
Classification: H04L,H04W

Abstract:
A connection control device for controlling data communication involving set-up of a connection provided on both sides of a communication source and a communication destination to control connection states of both sides in cooperation with a communication partner, each said device controlling communication between a data terminating equipment and a data circuit-terminating equipment on the side the device is disposed, comprising:connection holding means for holding the state of an established connection after a disconnection of a physical line; communication resuming means for resuming communication by said connection held after a re-connection of a physical line; communication resuming means for resuming communication by said connection held after a re-connection of a physical line; information storage means for storing information of a communication partner and information of a connection with said communication partner; and a control message communication means for transmitting and receiving information of a communication partner and information of a transition of said connection states to and from said communication partner as a control message; wherein said state of a connection with a communication partner has three kinds of communication states: a release state indicative of a state where a physical line is disconnected and a connection is released, a communication state indicative of a state where a physical line is connected and a connection is established, and a wait state indicative of a state where a physical line is disconnected while holding a connection, and said connection control device further comprises control means for processing a transition of said connection states; wherein when receiving an instruction of a kind designated for controlling a connection of communication from said data terminating equipment, said control message communication means transmits said control message indicative of information of the instruction in question to said communication partner prior to execution of the instruction, every time a new connection is established, said information storage means stores information of a communication partner having the connection in question and information of the connection in question, and when at the communication state, a physical line is disconnected without receiving a notification of a communication disconnection by said control message from a communication partner, information stored in said information storage means is held as it is to make a transition to the wait state without executing processing of communication end by a disconnection of a physical line with respect to said data terminating equipment.