On the Handover Security Key Update and Residence Management in LTE Networks

Abstract

Abstract-In LTE networks, key update and residence management have been investigated as an effective solution to cope with desynchronization attacks in mobility management entity (MME) handovers. In this paper, we first analyse the impacts of the key update interval (KUI) and MME residence interval (MRI) on the handover performance in terms of the number of exposed packets (NEP) and signaling overhead rate (SOR). By deriving the bounds of the NEP and SOR over the KUI and MRI, it is shown that there exists a tradeoff between the NEP and the SOR, while our aim is to minimise both of them simultaneously. This accordingly motivates us to propose a multiobjective optimisation problem to find the optimal KUI and MRI that minimise both the NEP and SOR. By introducing a relative importance factor between the SOR and NEP along with their derived bounds, we further transform the proposed optimisation problem into a singleobjective optimisation problem which can be solved via a simple numerical method. In particular, the results show that a higher accuracy of up to 1 second is achieved with the proposed approach while requiring a lower complexity compared to the conventional approach employing iterative searches.

Enhancing Security of MME Handover via Fractional Programming and Firefly Algorithm

“…Specifically, in Fig. 10(a), the initial population of fireflies are generated over the 2-D grid with a notice that their location should satisfy the OPV constraint (33) where the the target maximum OPV and the vulnerable interval threshold are α = 0.01 and τ th = 5 seconds, respectively. It can be observed in Fig.…”

“…This work is extended from[33] where only the impacts of the KUI and MRI were considered on the optimisation of handover security performance. We now take a further step with the analysis of the OPV and the proposal of two approaches for solving the developed MO problem.…”