Although the security properties of 3G and 4G mobile networks have significantly improved by comparison with 2G (GSM), significant shortcomings remain with respect to user privacy. A number of possible modifications to 2G, 3G and 4G protocols have been proposed designed to provide greater user privacy; however, they all require significant modifications to existing deployed infrastructures, which are almost certainly impractical to achieve in practice. In this article we propose an approach which does not require any changes to the existing deployed network infrastructures or mobile devices, but offers improved user identity protection over the air interface. The proposed scheme makes use of multiple IMSIs for an individual USIM to offer a degree of pseudonymity for a user. The only changes required are to the operation of the authentication centre in the home network and to the USIM, and the scheme could be deployed immediately since it is completely transparent to the existing mobile telephony infrastructure. We present two different approaches to the use and management of multiple IMSIs.
Dupr 'e @cite_25 presents a process to control a subscriber identity module (SIM) for mobile phone systems. He provides generic guidance regarding the transmission of control information from the network to the SIM. The schemes described in this paper extends Dupr 'e's idea in a more concrete way.
@cite_25
344917603 2112207969 2002455623 2023924043
A process to control a subscriber identity module (SIM) in mobile phone systems. The process consists of the mobile phone network sending one or more specific control values to the subscriber identity module that initiate specific actions or procedures within the subscriber identity module. Certain random values sent by the mobile phone network to the subscriber identity module for regular authentication purposes are used as control values (Control RANDs). Identity privacy is a security issue that is crucial for the users of a cellular network. Knowledge of the permanent identity of a user may allow an adversary to track and amass comprehensive profiles about individuals. Such profiling may expose an individual to various kind of unanticipated risks, and above all may deprive an individual of his right to privacy. With the introduction of sensitive services like online banking, shopping, etc. through cellular phones, identity privacy has now become a bigger security issue. In GSM and UMTS, the problem of user identity privacy vulnerability is proven to exist. In both these systems, there are situations where the permanent identity of a subscriber may get compromised. Long Term Evolution (LTE), which evolved from GSM and UMTS, is proposed by 3GPP for inclusion into the fourth generation of cellular networks. Although security of LTE has evolved from the security of GSM and UMTS, due to different architectural and business requirements of fourth generation systems, LTE security is substantially different and improved compared to its predecessors. However, the issue of identity privacy vulnerability continue to exist in LTE. In this paper, we discuss how the security architecture of LTE deals with identity privacy. We also discuss a possible solution that may be utilised to overcome the problem of user identity privacy in LTE. To guarantee the secure access by authorized subscribers in mobile pay-TV systems, user authentication is required. User authentication is a security mechanism used to verify the identity of a legal subscriber. In 2012, Yeh and Tsaur proposed an authentication scheme for access control in mobile pay-TV systems to improve the Sun and Leu's scheme. Yeh and Tsaur claimed that their scheme meets all security requirements for mobile pay-TV systems. However, this paper indicates that Yeh and Tsaur's scheme suffers from some critical weaknesses. An attacker without knowing secret information can successfully impersonate both mobile sets and head-end system. As a remedy, we propose an improved authentication scheme for mobile pay-TV systems using bilinear pairings. The proposed scheme maintains the merits and covers the demerits of the previous schemes, and provides a higher level of the efficiency for mobile pay-TV systems. Mutual authentication is important in a mobile pay-TV system. Traditional authentication schemes make use of one-to-one delivery, that is, one authentication message per request is delivered from a head-end system to subscriber. This delivery occupies too much bandwidth and therefore is inefficient and costly. One-to-many authentication scheme for access control in mobile pay-TV systems was proposed by in 2009. In one-to-many authentication scheme, only one authentication message for multiple requests is broadcasted from the head-end system (HES) to subscribers. claimed that their scheme is secure and provides anonymous authentication for protecting user privacy. However, the authors demonstrate that their scheme has a critical weakness. An attacker without any secret information can not only successfully impersonate mobile set (MS) to cheat the HES but also impersonate HES to cheat MS. The authors result is important for security engineers who design and develop user authentication systems. Afterwards, the authors design a novel one-to-many authentication scheme from bilinear pairings. They give the formal security proof in the random oracle model. In addition, they present the performance analysis of our scheme. The analysis results showed that their novel authentication scheme has shorter transmission message and can be applied in the environment which has limited bandwidth. At the same time, their scheme is also the first secure one-to-many authentication scheme for access control in pay-TV systems.