Band control system, load distribution device and band control device

The invention provides a band control system, a load distribution device and a band control device. Band control is conducted for each user by distributing traffic for each user in a case where a plurality of band control devices are required due to increased traffic and under the condition where the user uses a plurality of terminals or has a plurality of IP addresses with one terminal to generate a plurality of communications at the same time. The band control is performed for each user, using a load distribution device for specifying a user identifier such as a contractor number or telephone number from the source IP address used by the users in making the communication, and transferring the traffic based on the user identifier, a user management device for managing the correspondence between the user identifier and the source IP address, and a plurality of band control devices for managing the traffic for each user identifier, and making the band control of traffic for each user through a transparent proc