security aspects in UMTS network

Cellular Internet access Yet, security and privacy issues in femtocell-enabled cellular networks, such as UMTS and LTE, still need to be fully addressed by the bodies.we review significant threats to the security and privacy of femtocell-enabled cellular networks. We also propose novel solution directions in order to tackle some of these threats by drawing inspiration from solutions to similar challenges in wireless data networks such as WLANs and mobile ad hoc networks (MANETs).

                               

The use of mobile devices has changed since the advent of digital technologies such as GSM. What started as a voice only service, has been upgraded mobile networks are used by more than 4 billion users worldwide. One effective way to meet the increasing demand for data rates is to deploy femtocells, which are low-power base stations that connect to the mobile operator through the subscriber’s residential to support data traffic as well. With modern smartphones, users are able to browse the Inter-net and obtain services such as ebanking, navigation, social networking and recommendations based on the subscriber’s location. Femtocells, which are low-power and low-range base stations for cellular networks installed by users at their own premises, are believed to meet the surge in data rates that these multimedia and interactive services require. They offload the macrocell network and provide backhaul connections to the cellular operators’ networks through the users’ residential broadband accesses.

Long Term Evolution (LTE) is the mobile network tech-nology for the next generation mobile communications, as defined by the 3rd Generation Partnership Project (3GPP). In addition to features such as increased data-rates, lower latencies and better spectral efficiency, one of the most in-teresting aspects is the radically novel all-IP core network architecture, known as Evolved Packet Core (EPC). LTE is expected to make extensive use of user-installed femtocells, in order to achieve its goals of spectral efficiency and high-speed for a greater number of users. It is clear that the sensitivity and confidentiality of users and data transiting in such digital cellular networks is paramount both to businesses and private users.

The issue of user identity protection was already raised in the early GSM networks, and the solution that has been adopted ever since has never been substantially revisited. With the ongoing migration towards all-IP and femtocell-enabled cellular networks, the legacy solution might not be appropri-ately suited anymore. In fact, GSM, UMTS and LTE standards mandate the use of unlinkable temporary identifiers  to protect the identity of mobile devices at the air interface, but the capillary deployment of femtocells might render this insufficient to guarantee a satisfactory level of protection for the users. TMSIs  are usually unchanged in a given location (or tracking) area, which is composed by up to a hundred adjacent cells, and femtocells could make it possible for malicious users not only to track the movements of mobile subscribers, but due to the low range, to have an unprecedented accuracy as well. For instance, such tracking attacks could be perpetrated by curious employers, in order to monitor whether an employee is visiting a competitor, or by governmental agencies, in order to illegitimately track people’s locations.