cted about the network: Solution required and technology Network elements, quantity, capacity and site location Site availability/spare capacity Transmission requirements and interfaces Existing transmission network Required services and new product roll-out schedule Subscriber forecasts Numbering plan Network topology Geographical information Charging plan and data used Traffic measurements A careful evaluation of project requirements is needed to determine which part of this information is necessary in the process of network assessment. The requirements may vary from project to project and not all of the above information may be relevant to every project. Network Design Process Table 4.1 Subscriber forecast Phase_1 Phase_2 Phase 3 MSC_01 130 000 210000 350000 MSC-02 112000 182000 240 000 MSC_03 190 000 260 000 MSC_04 50 000 Table 4.2 Subscriber categories Phase_1 Business Post-paid Pre-paid Network Subscriber Forecast An important input and key parameter required for network dimensioning is the number of subscribers forecasted and the subscriber growth for each of the next phases of network growth. These are usually provided by the operator's marketing department. In the absence of such data, a market service penetration forecast may be used. If market service penetration is assumed, a population census of the main population centres may be used to determine the number of subscribers expected from these centres for each phase and each service. The geographical distribution of the subscribers will in this case be directly proportional to the population distribution. It is easier to assume switching locations in the major population centres or cities to reduce transmission costs. The number of subscribers in each switch at the end of each phase can therefore be presented in table form, enabling the network design engineer to estimate the required number of network elements (Table 4.1). Sometimes it is possible to specify the percentages of different users, i.e. business users, post-paid users and pre-paid users (