COMMUNICATION EQUIPMENT

摘要

PURPOSE:To obtain a system having link fault detection capacity and enabling the saving of communication expense by performing a link fault detection only when the transmission/reception of a data packet exist. CONSTITUTION:A call setting procedure part 1 sets a call with a public network and a communication procedure part 3 realizes the transfer of a data packet and a link quality monitoring monitor packet with an opposite connection 2. Each part 1 and 3 shares a flag 4 showing the presence or absence of the transmission/reception of the data packet within arbitrary unit time and a flag 5 showing a call setting state. The absence of the traffic of the data packet is detected and the call with the public network is disconnected. When the traffic of the data packet does not exist, the charging in the public network is suppressed by disconnecting the call with the public network.