anners have to take forecasts into account because switches are expected to cater for the expected traffic rise for a few years before their number is increased. Network analysis requires data ranging from subscriber information to demographic information. The major dataset constitutes existing network data, the existing service plan, subscriber base data, topographical data, and traffic data (both existing and forecast). Apart from these, some radio network planning data and/or transmission planning data might also be needed. Existing network data gives the core-planning engineer information about the number of sites and the traffic it is expected to generate. The total traffic within a network usually consists of traffic that is generated within the network and traffic that was generated outside the network (e.g. calls being made to mobile subscribers from fixed lines). This traffic distribution is very helpful during both the planning and optimisation phases of the core network. The next thing to find out about is the services to be delivered to mobile subscribers, and the traffic it is expected to generate. Apart from voice, this generally includes value-added services such as SMS, MMS, Internet, etc. Subscriber base data is one of the major inputs for switch planning. It includes the exist- ing subscribers or subscribers expected at the time of network launch, the expected traffic that will be generated by these subscribers, forecast subscribers and forecast traffic. The forecast may be in phases that may depend upon expansion of the network or the subscriber base. The information related to the different regions (urban, rural, hot spots, etc.) and the type of subscriber base (business users, residential users, etc.) will give a fair idea of the expected traffic. Other useful information comes from a numbering study, including roam- ing numbers, IMSI numbers, signalling point codes (SPC), emergency numbers, allotted subscriber numbers, etc. 4.2.2 Network Dimensioning All the information collected during the 