THE MAC FORWARDING METHOD FOR MULTI-HOP ROUTING IN AUTOMOBILE COMMUNICATION SYSTEM

摘要

A MAC(Media Access Control) forwarding method for multi-hop routing in an inter-vehicle communication system is provided to offer various application services of an inter-vehicle communication system and enable high-speed multi-hoc routing by using a forwarding method in the MAC layer in executing multi-hop routing for ad-hoc communication between vehicles. A node receives a frame, and judges whether the received frame is a repeated frame(201). If so, the node partially updates FCT(Forwarding Cache Table) information(202). Then, if Retry_flag of the received frame is "0", the node sends a d_ack(delay acknowledge) frame(204). If not, the node discards the frame(220). In case the received frame is not a repeated frame, the node updates SNT(Sequence Number Table) information(205). Then, the node confirms whether the destination address is its own(206). If so, the node updates FCT information(207), sends an Ack signal(208), and forwards the frame to an upper layer(209). In case the destination address is not address of the node, the node checks whether the frame is registered as a destination address in the FCT(210). If so, the node updates FCT information(211), sends a d-ack frame(212), and inserts an implicit unicast frame into an IFQ if the d-ack frame is successfully sent(214).