| 摘要 |
PURPOSE:To ensure a minimum line with respect to a VIP by providing a traffic monitoring function to an exchange accommodating each portable master set in a broad band portable telephone system and permitting outgoing/incoming call to a VIP portable equipment only at congestion. CONSTITUTION:Exchanges 1-5 are connected in the hierarchy constitution and plural portable telephone sets T are accommodated in a 1st class exchange 1 in the lowest layer via a portable master telephone set. The 1st class exchange 1 applies the following VIP(very important person) service when the traffic exceeds a predetermined quantity to be an abnormal congestion. That is, when an incoming call signal comes to its own exchange, the call from the VIP portable telephone set only is accepted. As to the outgoing call, only the outgoing call from the VIP portable telephone set is permitted. Furthermore, as to the location registration of its own service area, it is allowed only for the VIP portable telephone set. |
