The goal of 3GPP long term Evolution/system ArchitectureEvolution (LTE/SAE) is to move cellular cellular wireless technology into its fourth era. One of the precise challengeing situations of fourth-technology generation is the way to near a security gap through which a single compromised or malicious tool can jeopardize a whole cellular network due to the open nature of those networks. To fulfill this challenge, handover key management in the 3GPP LTE/SAE has been designed to revoke any compromised key(s) and accordingly isolate corrupted network devices. This project but identifies and information the vulnerability of this handover key management to what are referred to as desynchronization attacks; such attacks jeopardize secure communication between customers and mobile networks. Despite the fact that periodic updates of the root key are an critical part of handover key management, our work here emphasizes how crucial those updates are to minimizing the effect of desynchronization attacks that, as of now, can not be successfully prevented. Our essential contribution, however, is to explore how network operators can determine for themselves an optimal interval for updates that minimizes the signaling load they impose while protecting the security of user traffic. Our analytical and simulation studies demonstrate the impact of the key update interval on such performance criteria as network topology and user mobility.