AbstractA new network design algorithm called “NABLE” (network constructing algorithm based on link significance evaluation) is proposed for constructing future circuit‐switched telecommunications networks. First, this algorithm creates synthetically a backbone network by utilizing a new concept called “link significance.” Then it adds other links to the created network. The flowchart for constructing a network based on this concept is explained. Design examples on digital 64 kbit/s and high‐speed/ broadband circuit‐switched networks show that NABLE is a powerful heuristic algorithm for total network optimization. NABLE can be used in practice for the long‐range planning of various ty