Wireless communications has experienced a rapid development and an increasing number of services are provided by many different operators. Users expect high quality and uninterrupted provision of the services even cross borders, which entails change of operator providing the services. In such so called roaming scenarios, it may be difficult for an operator of a network to estimate the number of roaming users roaming into a network and leaving a network and hence how to make best use of communication resources.
With an increasing number of operators, the market of providing wireless services is becoming competitive and tough. It is in the best interest of all the operators to find ways of improving their services and increasing user satisfaction.