An effective Caching on Forwarding Table Scheme for Metro Ethernet

Metro Ethernet has recently attracted remarkable attention due to its simplicity and low cost. Although Ethernet is the dominant technology in the Local Area Network (LAN) which usually handles small number of nodes, when deploying in Metropolitan Area Networks (MANs), it faces certain challenges. One major challenge is its broadcasting based address resolution scheme. A broadcast-based address resolution scheme triggers many broadcast messages in a network, and hence make the Ethernet unscalable. This paper proposes a cache scheme, called Caching on Forwarding Table (CFT), to reduce broadcast messages for Metro Ethernet. CFT caches end user's Address Resolution Protocol (ARP) entries by inserting an IP address in each forwarding entry. If an ARP request is answered by a cached entry, the broadcast is stopped. Hence CFT can significantly reduce the broadcast messages in the network. We also discuss how to cache ARP entries in a Metro Ethernet using End User Enabled MAC-in-MAC (MiM) scheme. The simulation results show that CFT can effectively decrease the communication messages for address resolution and make Metro Ethernet more scalable.