d to determine the key breaking points when more radio capacity is required or when SGSN/GGSN need to be integrated. Therefore, there should be a close follow-up of the dimensioning results together with the overall rollout plan of the customer, with regular updates in order to avoid unexpected expansions of the network due to higher-than-expected growth rates; or, on the opposite side, to avoid the deployment of excessive capacity for the true traffic demand. B.5 MMS PERFORMANCE MONITORING AND OPTIMISATION MMS application performance is measured in a number of ways: subscribers' complaints, network statistics and static/drive test measurements all provide a good starting point for analysis. One of the tasks is to perform some measurements, using test tools capable of generating automated MMS traffic, to provide meaningful KPIs (key performance indicators) to ac- curately reflect the end-user experience. Then the current performance of the network can be evaluated and any further action decided on. Data and statistics from the NMS (network management system) can also be used as indicators of network performance and MMS service performance. Another point is to identify current problem areas as well as potential bottlenecks in the delivery of MMS services as traffic increases. The network design (planning and dimen- sioning) can be reviewed with an emphasis on core and radio network configurations and dimensioning in line with the rollout plan. Consideration is also given to the interaction of MMS with other data applications as well as roaming and interoperability. Then, a comprehensive bearer investigation can be conducted to determine the perfor- mance of the main MMS traffic bearers, for instance the GPRS network. The key point of the bearer investigation is to simulate the end users and generate real traffic, including tracing and post-processing at all layers of the radio and core protocol stacks and at all points in the end-to-end network. Static tests determine the core network performance for MMS as well a