Patent ID: 7400634

Claim:
For use in a network providing a wide-area LAN service which allows communications to be performed between a plurality of second networks via a first network, a MAC address learning apparatus comprising edge switches located in said first network and connected to said second networks, wherein each of said edge switches comprises: a tentative learning registration means which, when a packet whose source MAC address and receiving port are not yet learned is received from said first network, registers said source MAC address and said receiving port in a tentatively learned state; a learned state changing means which, when a packet whose destination MAC address is registered in a learned state is received from an associated one of said second networks, changes the learned state of said destination MAC address to a permanently learned state; and a permanent learning registration means which, when a packet whose destination MAC address is registered in a learned state is received from said first network, registers the source MAC address and receiving port of the packet received from said first network in a permanently learned state.