Formulation of optimization problems for access selection in next generation wireless networks

Wireless Networks are rapidly evolving, constantly increasing both in coverage and offered bandwidth, while the vision for Next Generation Wireless Networks (NGWNs) encompasses a unified core network incorporating various Radio Access Technologies (RATs) in a unified and seamless manner. In such an environment providers would like to maximize their users' satisfaction, while at the same time avoid overloading their subsystems. In this paper we identify several aspects of access selection and resource allocation in NGWNs and provide different variations of optimization problems that seem to present significant interest in this context. All problem formulations seem to be NP-Hard, and our ongoing research focuses on designing approximation techniques for solving them.