Tabu search based approach to solve the TAs reconfiguration problem in LTE networks -

Abstract

Designing tracking areas (TAs) in LTE networks affects the signaling cost of user equipment (UE) during mobility. Indeed, when the latter is called, the mobility management entity (MME), which records the TA in which the UE is registered, broadcasts a paging message in the UE’s TA to determine the exact cell through which the call should be delivered. When a UE moves to a new TA, a TA update (TAU) might be performed either to update the MME or the home subscriber server (HSS), which is a database maintaining the subscriber’s profile, depending on whether the move is intra- or inter-MME. TA update and paging result in a significant amount of signaling overhead. The TA design is usually optimized during the network planning phase. However, the mobility of UEs might turn the initial TA configuration inefficient requiring TA reconfiguration. In this thesis, we use the tabu search (TS) heuristic to solve TAs reconfiguration problem in LTE networks taking into consideration both signaling overhead and reconfiguration cost. We compare our solution with a variation of the genetic algorithm (GA) based solution found in the literature and with the optimal solution obtained by formulating the problem using an Integer Programming Model (IPM) and implementing it using Gurobi optimizer.