Patent ID: 7660303

Claim:
A method for communication, comprising: coupling a group of switches in a Layer-2 bridged network, each switch comprising multiple network interfaces; configuring the interfaces so that at least one interface of at least one of the switches is configured as a first type of the interfaces, and a plurality of other interfaces are configured as a second type of the interfaces; upon receiving frames through the interfaces of the first and second types for transmission over the network, labeling the received frames with corresponding first and second type indications; forwarding the frames through the Layer-2 bridged network using the switches responsively to the type indications, such that the frames labeled with the first type indication are permitted to be transmitted through any of the interfaces, while the frames labeled with the second type indication are permitted to be transmitted through the interfaces of the first type and prevented from being transmitted through the interfaces of the second type; wherein forwarding the frames comprises, upon receiving through a first interface of a given switch a frame comprising a given destination address: looking up the destination address in a forwarding database, further containing an identification of at least a second interface through which the frame should be forwarded and a type designation of the destination address as being associated with the first or second type of the interfaces; and comparing the type designation with a type indication of the frame in order to determine whether to forward the frame through the second interface; receiving through a first interface of a given switch a frame comprising a source address; creating an entry comprising the source address and a type number equal to a type indication of the frame; adding the entry to the forwarding database; and updating the forwarding database using a database learning process responsively to the source address and to the type indication of the frame.