Distributed mobility management (DMM) requires a flattened cellular network architecture to meet ever-increasing traffic demands of mobile users. In order to get rid of centralized mobility entities, it is desirable to manage locations of mobile nodes (MNs) in a distributed but secure and fault-tolerant manner. To address such issues, in this paper, we propose a secure and fault-tolerant mechanism for DMM. The proposed mechanism utilizes a distributed hash table of access nodes for distributed location management, and a ticket-reuse approach is adopted for improving authentication performance while providing secure authentication of the MNs. We present an analytical model to calculate the processing time of a location query. We have evaluated the proposed security mechanism in terms of authentication latency and a number of authentication messages required for secure handover. Analysis results confirm that the proposed mechanism outperforms the popular existing authentication protocol, EAP-TLS, in a DMM environment.