Lots of related researches have shown that network failures occur inevitably and frequently on the Internet. When network failures occur, the currently deployed intra-domain routing protocol need to re-convergent. During the process of re-convergence, the packets may be lost due to inconsistent routing information, thus greatly reducing the Internet routing availability. LFA was proposed to cope with all the single failure scenarios. However, the existing LFA implementation algorithms are time-consuming and require a large amount of router CPU resources. This paper proves that when a single fault occurs in a network, it only needs to calculate the backup next hop for a specific node. The backup next hop of all the other affected nodes by the fault is the same as that of the specific node. Based on the above property, the paper proposes two routing protection algorithms to provide protection for networks with symmetric and asymmetric. The results show that these approaches reduce more than 90% computation overhead compared to LFA, and achieve less than 15% path stretch. Moreover, they can provide comparable protection ratio with LFA.