How to deal with network faults efficiently and quickly is the basic requirement and main task of designing routing protocol. When dynamic routing protocols deal with network faults, a large number of packets are discarded during dynamic convergence. Therefore, at present, router manufacturers generally use routing protection methods to overcome network failures. Among many route protection methods, the DC(downstream criterion) rules is a generally recognized method. However, the time complexity of the existing DC rules algorithms is generally high, and the complexity increases rapidly with the increase of the average degree of network nodes. In order to deal with the above problems, this paper proposed a linear time complexity university routing protection scheme ERPLR(efficient routing protection method with linear time complexity). The method firstly proposed the backup next hop calculation rule, and then calculated the backup next hop for all source-destination node pairs based on the existing shortest path tree according to the backup next hop calculation rule. In the process of calculating the backup next hop, accessing each node and its neighbors at most once, so the time complexity of ERPLR is O(V+E). The experimental results show that, compared with the existing rules for implementing DC rules, ERPLR has similar results in four metrics: failure protection ratio and path stretch. Compared with DC rules, ERPLR reduces the computational overhead by about 74.93% and 78.91% in real topology and generated topology, respectively, this method can greatly reduce the calculation cost of DC rules.

[2023-01-06] Accepted Paper /doc/2022.11.0521/v1

[2023-06-05] Printed Article /doc/2022.11.0521/v2