Recent advancements in cellular networks have led to the demand of ‘any-where’ service - immaterial of the location of the user or the coverage area of the service provider. The increasing demand for providing subscribers with services beyond ones home service area necessitates the service providers to set up elaborate trust relationships and agreements amongst themselves, to ensure secured and reliable service to the genuine subscribers. This process however limits the ease and span of extending the services by a service provider. In addition, it is important that such services are provided without compromising the identity privacy of the subscriber. While identity privacy is an accepted requirement, vulnerability of the same remained across the generations. Newer threat like location tracking and comprehensive profiling - wherein data about movement, usage, etc., of a subscriber is amassed and linked to his/her identity to explore various attacks - has been identified. Much of the aforesaid limitations can be attributed to the trust model adopted by the cellular networks. In this article, we highlight the benefits of a trust model that may contribute towards reducing the complexities of a-priori agreements amongst service providers, for providing service beyond their territories in future mobile networks.

Roaming agreements, Authentication, Anonymity, IMSI, Privacy

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