Network switching apparatus for redundancy gateway system

摘要

A network switching apparatus which is provided between a redundancy gateway system and a packet network and enables an uninterruptible changeover in a system changeover to be performed. The apparatus includes an up-direction transfer unit and a down-direction transfer unit. The down-direction transfer unit receives a changeover notification packet accompanied with designation information of a new active system gateway apparatus which has newly been set in place of an active system gateway apparatus. After the reception of the changeover notification packet, only in the case where a down-direction packet which is newly transmitted by the packet network is accompanied with designation information of the active system gateway apparatus before the changeover, the down-direction transfer unit changes the designation information to the designation information of the new active system gateway apparatus, thereby transferring the down-direction packet to the new active system gateway apparatus.