Abstract—In hierarchical mobile ad hoc networks, the architectual stability is a key factor in determining the network performance. There are many solutions proposed to construct stable clusters, none of which has however revealed the maximum stability attainable in the mobile environments. In this paper, we define two metrics to measure the stability of hierarchical networks: the cluster lifetime and the inter-cluster link lifetime. We model and analyze the maximum of these two lifetimes with consideration of node mobility. The analytical understanding of maximum stability provides a guideline for the clustering and routing protocol design to optimize network performance.