Forwarding model of backplane Ethernet for open architecture router

Diversified IP services have recently required flexible and scalable edge routers to support advanced service functions such as IPsec VPN and application layer firewalls. However, those functions cannot be integrated into existing routers easily, and this prevents required routers from becoming available. A common forwarding model of backplane Ethernet for a router supporting separate control, line, and service cards is proposed in this paper. This model enables an open architecture router that has multivendor control, line, and service cards, where packets are forwarded among them based on a common method of backplane routing. It supports inline, host, and tap service cards. We propose an efficient forwarding decision-making algorithm in terms of the required speed and efficiency of table lookup and demonstrate that the method requires half the table lookup processing resources compared with those of a naive method.