The conceptual basis of the STEM modelling system is a unique method for representing, in a structured manner, the relationships between demand and the resources required by a telecommunications operator to meet that demand as it evolves.
By varying the level of detail at which demand and resources are represented in a model, it is possible to create a consistent description of a complete operator (such as a national telecommunications operator offering voice and data services, local, national and international calls) or of any part of it (such as the access network).
Once an operator, or a part of it, has been represented in this way, STEM allows the user to describe alternative strategies and then compare the consequences of those strategies over the course of time. In particular, the way in which demand is met by different equipment types may change over time, so that a given proportion of new and replacement demand for a particular service might be met by, for example, optical fibre rather than copper access links after a given date.
Alternatively, the user may wish to build a number of models to study the effect of the use of different technologies in the local access network and compare their results.
Apart from the implementation strategy, other ‘levers’ over which the user has control include growth of demand, tariffs, capital and operating costs of equipment, and cost trends. By altering these variables and comparing the results, the user can assess the robustness of alternative strategies.