Currently all PC(s) are connecting by cable into a switch in a group(Look Like Star Network Topology). The switch connecting each others to form a line network topology. Hence, line network implicated the lost of connection when one of the switch is switch off or one of the switch is breakdown. I would like to overcome this problem, so i think of Ring Token to form a loop of network. However, I faced a problem. The switch i used could not link back itself after a circle of loop ( perhaply, only can be one direction ). Therefore, I hope any person can help me design a suitable network topology to overcome my problem. Thanks a lot.