Network engineering is the process of meeting the users and applications requirements. The design process starts from requirements analysis, then through capacity planning to the architecture high-level design to the detailed design of your network.
When talking about data networks design, we are talking not only about the technical part of it, but also about the financial and economical parts. It is very easy to "through throughput at the problems" as some do, but it more difficult to perform an adequate design, that will meet the customer's requirements, and this is our expertise.