| 摘要 |
PROBLEM TO BE SOLVED: To improve communication efficiency.SOLUTION: An L2 tunnel termination device establishes an L2 tunnel between a termination device disposed in an opposed network and itself. When an RA message transmitted from a router contains specification of an MTU value indicating the maximum data size which can be transmitted at a time by a user terminal, the L2 tunnel termination device calculates, from the MTU value and an overhead size of packets passing through the L2 tunnel, a data size which can pass through the L2 tunnel. On the other hand, if the RA message does not include the MTU value, the L2 tunnel termination device calculates, from predetermined designated data size and overhead size, a data size which can pass through the L2 tunnel. Then, the L2 tunnel termination device transmits the calculated data size, as a maximum data size, to the user terminal. |
