Abstract：Existing routing protection schemes do not accurately consider the relationships between the failure protection ratio and the path stretch. A simple IP fast reroute based on the segment routing (IPFRRBSR) algorithm is given here to consider these relationships. IPFRRBSR calculates two paths between each source-destination pair with one being the shortest path and the other being a backup path constructed using segment labels. The packets are forwarded along the shortest path when the network is in the normal state, but are forwarded along the backup path when a network failure occurs. Since the shortest path and the backup path (except for the source and destination nodes) do not have any common nodes, the probability of them failing simultaneously is very low. Tests show that IPFRRBSR can deal with single node failures in the network and has a small path stretch.
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