An Effective Target Cell Selection Scheme for Next-generation Open-access Femtocell Networks

Femtocell technology is a promising solution for offloading high volume cellular data traffic to low-powered indoor base stations. It allows users to perform a handoff (HO) to a femto base station (FBS) and get high data rate. Despite the importance of selecting a proper target femtocell in open-access femtocell networks, effects of attacks on the target cell selection have not been paid sufficient attention. Unlike traditional cellular networks, attackers can get root access to FBSs and perform a number of attacks utilizing these FBSs. Unfortunately, existing target cell selection and HO decision algorithms are not sufficient to detect or avoid these attacks. Moreover, existing solutions to avoid these attacks in femtocell networks cannot be directly used in the HO scenario. In this paper, we first discuss possible attacks and their effects on femtocell networks during an HO process. In addition, we propose a target cell selection and HO-decision scheme which helps a user to select a trustworthy target femtocell during an HO. As the attacks are unalike in nature, it is hard to come up with a single solution which can avoid all these attacks we consider. We use both received signal strength indicator and location database of FBSs to select a target cell in a way that the probability of HOs to a malicious femtocell is reduced without increasing the HO signaling cost significantly. Additionally, simulation results exhibit significant improvement of the femtocell utilization. To the best of our knowledge, this is the first work that considers attacks on FBSs during HOs in open-access femtocell networks.