Abstract: To compare communication link importance in communication networks invulnerability，a algorithm based on link-contraction is proposed.The algorithm compares the number of spanning trees after every link is contracted，and estimate every link importance in communcation networks invulnerability，the more the number of spanning trees，the more important this link，and the more its effection to communication networks invulnerability.Experimental results show the algorithm is simple and can reflect link importance in communication networks invulnerability more precisely.

摘要： 为了比较通信链路在通信网抗毁性中的重要性，提出了一种基于链路收缩的算法。该算法通过比较每条链路收缩后的通信网生成树数目，判断每条链路对通信网抗毁性影响的重要程度，生成树数目越多，表明该链路越重要，对通信网抗毁性的影响越大。实验结果表明，该算法计算简单，可以精确地反映不同链路对通信网抗毁性的重要程度。