TRAFFIC CONTROL SYSTEM AND TRAFFIC CONTROL METHOD

PROBLEM TO BE SOLVED: To provide a traffic control system and a traffic control method which prevent dual control to the same congestion in the IP network. SOLUTION: After performing congestion control to an originating call from an IP telephone 1, a subscriber call control device 2 adds an original header indicating that the congestion control is already performed to the SIP message of the originating call to relay it to a first relay call control device 3. When the original header is added to the SIP message of the originating call which is relayed from the subscriber call control device 2, the first relay call control device 3 relays the originating call transparently to a second relay call control device 4 without performing congestion control. COPYRIGHT: (C)2011,JPO&INPIT