Patent ID: 7778623
Filing Date: 2010-08-17
Classification: H04W,Y02D

Abstract:
1. A communication system comprising: a first terminal configured to be connected to a first communication network, the first terminal being assigned a terminal ID and being driven by power supplied from a battery; a server apparatus configured to be connected to a second communication network that is different from the first communication network, the server apparatus being configured to periodically confirm the presence of the first terminal, to periodically confirm the presence of a second terminal that is configured to be connected to the second communication network, and to communicate with the first and the second terminals if they are present; and a controller configured to cause the server apparatus to monitor the presence of the first terminal on the first communication network according to a second period of time that is longer than a first period of time according to which the presence of the second terminal on the second communication network is monitored.