Effects of multiple access alternatives in heterogeneous wireless networks

The future mobile telecom systems will consists of a set of different radio access networks. A typical scenario will consist of at least one network that covers wide geographical area supplemented by so-called hot spots that provides higher bandwidth access within limited areas. When the user finds himself in these hot spots he will frequently have to choose which wireless link to use to connect to the core network according to his needs and the characteristics of the available wireless networks. There will be a handover algorithm that takes these decisions on behalf of the user. Different handover algorithms will choose different wireless networks and correspond in a varying degree to the user´s needs. In other words, the user may be more or less satisfied with his telecom services depending on which handover algorithm is used. In this paper, an approach to evaluate the user satisfaction in such a scenario is described. A set of simple mobility models and handover algorithms are used to illustrate this approach, and a user satisfaction function will determine which handover algorithm is best for the various scenarios. The mobility models, the handover algorithms and the user satisfaction function presented are simple, but they will nevertheless serve as good illustrations of how to approach the problem of user satisfaction in overlay networks. Further study can develop these models more, incorporating other parameters and features, and thus get more detailed and realistic estimates of the user satisfaction using the same principles as outlined in this paper.