The present invention provides a network device, such as a network switch or a router, having a high degree of modularity and reliability. The network device includes a data plane and a control plane. The data plane relays datagrams between a pair of receive and transmit network interface ports. The...http://www.google.com.hk/patents/US6639910?utm_source=gb-gplus-share專利 US6639910 - Functional separation of internal and external controls in network devices
