Nowadays mobility is a field of great importance. The fact of travelling or moving should not mean the rupture of the connection to the Internet. And the current objective is not only to be world-wide connected, it is also to be it always through the best available connection (ABC). It means the need to perform vertical handover to switch between different networks, while maintaining the same Internet connection. All this has to be done in a transparent way to the user. In order provide the highest Quality of Experience some tools are needed to enable checking the status and performance of the different available networks, measuring and collecting statistics, in order to take advantage of each one of them. This thesis presents the theoretical base for a measurement module by describing and analysing different metrics, with special emphasis on delay jitter, collecting and comparing different methods, and discussing their main characteristics and suitability for this goal.