스패닝 트리 프로토콜을 이용한 브릿지 시뮬레이션

A Simulation of Bridge using the Spanning Tree Protocol

MAC (media access control) bridge is used to interconnect separate LANs and to relay frames between the BLANs (bridged LANs). Bridge architecture consists of MAC entity, MAC relay entity and bridge protocol entity and performs learning, filtering and forwarding functions using filtering database. In this paper, we simulate these functions of bridge and the SIP (spanning tree protocol). The SIP derives an active topology from an arbitrarily connected BLAN. Our simulation model assumes a BLAN consisted of three bridges forming a closed loop. In order to remove the loop, each bridge process exchanges configuration BPDU (bridge protocol data unit) with other bridge processes connected to the bridge itself. To simulate the communication between bridges, we implement the IPC (inter-process communication) server using message queues. Our simulation results show that the assumed BLAN contains no closed loop and then there is no alternative route and no unnecessary traffic.