Patent ID: 8184527

Claim:
A method for conducting redundancy checks in a chain network, wherein the network architecture includes a chain network with a plurality of switches; the chain network have at least two switches at both ends, namely a first switch and a second switch; one or more relay switches are connected between the first switch and second switch, both of which are connected with an external network respectively; the method for handling redundancy mechanisms comprising the steps of: (A) the port of the second switch connecting with the external network is set to blocking state, while ports of other switches of the chain network are set to be forwarding state; (B) If any communication failure happen in the chain network, the port of the switch that is linked with the both side of failure will be blocked; (C) the two switches whose blocking the link fail point send a first control packet to the first switch and second switch respectively; (D) the port of the second switch that is originally set to blocking state changes to forwarding state after receiving the first control packet.