DMME: A Distributed LTE Mobility Management Entity

Abstract

DMME is a distributed architecture that implements mobility management for next-generation cellular systems. It has been designed to serve as a scalable and cost-effective drop-in replacement for the Long Term Evolution (LTE) mobility management entity (MME). DMME is an example of a flexible control plane architecture that can be deployed incrementally across operator networks: processing locality is obtained by assigning control plane events to a local DMME replica and by allowing the transparent migration of control plane state across the different replicas as the users move. We evaluate the DMME scheme via analysis and simulation under several deployment scenarios, using mobility patterns drawn from both synthetic models and traces collected in a production network. Our analysis shows that DMME can achieve performances that are comparable with a centralized, server-based infrastructure in terms of system availability and signaling delay. Furthermore, we propose and evaluate a set of heuristics based on user behavior that specify the allocation policy of DMME instances over the available replicas. We also report preliminary performance figures from our DMME prototype implementation. Our results confirm that distributed architectures are a viable choice to reliably support high-throughput, latency-sensitive control plane functions such as cellular mobility management. © 2012 Alcatel-Lucent.