The link of backbone optical communication network is easily destroyed

resulting in communication failure.Therefore

it is important to identify the link importance of backbone optical communication networks and determine the protection level of links according to the link importance.In topology of backbone optical communication network

this paper first calculates the natural connectivity of the network

and defines the weighted natural connectivity by taking the zero eigenvalues of the Laplace matrix as the weight of the natural connectivity.By analyzing the impact of link failure on network invulnerability with the weighted natural connectivity

the link topology importance is quantitatively calculated

which can realize the identification of the link importance in the backbone optical communication networks.Finally

the algorithm in this paper is expounded.Taking a model of specific power communication optical backbone network as an example

the effectiveness and accuracy of the proposed algorithm are verified by comparison with other algorithms.In addition

it is demonstrated that the weighted natural connectivity is more comprehensive and reasonable in evaluating link importance than natural connectivity.