Communication system, a communication method and communication terminal

摘要

A service of reducing the number of tunnels in exchange for a specified service fee. A communication system, which generates tunnels in physical lines and multiplexes a plurality of sessions on the physical lines, comprises a monitor unit for monitoring the state of use of tunnels and sessions used by the user when the user using a plurality of tunnels is a customer who requires service of reserving sessions in a smaller number of tunnels in exchange for a specified service fee; a tunnel/session control unit performs control so as to gather the plurality of sessions of said user in a specified tunnel when the sessions currently used by the user can be reserved in a smaller number of tunnels; and a charging unit for charging a usage rate according to the number of tunnels or the number of physical lines used.