Patent ID: 7583685

Claim:
A gateway device which connects a first network and at least one second network and performs communication based on a call control protocol with a terminal device on the first network, comprising: a connection detecting unit which detects appliances on the at least one second network; an identification information generator which generates identification information of each of the detected appliances for identifying by the call control protocol each of the detected appliances; a classification unit which groups the detected appliances according to at least either control protocols with which the detected appliances comply or the second networks to which the detected appliances belong such that appliances complying with same control protocol belong to same category group or appliances belonging to same second network belong to same category group; a storage unit which stores the identification information of the detected appliances while associating the identification information of the detected appliances with respective category groups; an information publishing unit which, upon receipt of an information subscription request according to the call control protocol from the terminal device on the first network, publishes for the terminal device on the first network, of the control protocols or the second networks to the terminal device, and upon receipt of data designating one of the control protocols or the second networks, publishes for the terminal device identification information of appliances which is included in the group of the designated one; a call connection unit which, upon receipt of a request for call connection with the identification information of an appliance according to the call control protocol from the terminal device on the first network, establishes call connection with the terminal device having made the request for call connection; and a mediation unit which mediates communication between the terminal device having made the request for call connection and the appliance on the second network assigned the identification information serving as a target of the request for call connection.