A method for creating a single
virtual LAN including a source (S) attached to a first
Token ring LAN (N1), a target (T) within a subnet attached to a different
Token ring LAN (N2), and an interconnecting
router (R). The source (S) encapsulates the first packet with a
Token ring header including the
router MAC address (RMAC), SMAC as source
MAC address as layer 2 information, and
IP address of T (TIP) as layer 3 data and sends this packet over N1 toward the
router. When receiving the first packet, R reads its IP table for best match with TIP address to identify the subnet including T. The net handler runs an ARP protocol to identify TMAC address, substitutes the MAC header with said TMAC address into said first packet destination
MAC address field and forwards said first packet over N2. R then sends a conventional ICMP message over N1 limited broadcast and reconfigures itself in
proxy ARP for the defined subnet. For the second packet, S runs an ARP and R answers with RMAC address and the RIF data to be used for next packets.