TEXPO

Network & Data Communication

TEXPO provides consulting services in both network & data communication design and implementation. A network is a collection of cables, computers and devices and requires a lot of thinking and creativity to design an optimized network. Our analysts interact with the clients to gather their requirements and propose solutions that can meet their demands. Instead of proposing a single solution our analysts propose multiple solutions with scalability, performance and cost implications.

Network planning and design is an iterative process, encompassing topological design, network synthesis, and network realization and is aimed at ensuring that a new network or service meets the needs of the subscriber and operator. The process can be tailored according to each new network or service. A traditional network planning methodology involves five layers of planning, namely:

• Business planning
• long-term and medium-term network planning
• short-term network planning
• IT asset sourcing
• Operations and maintenance

Each of these layers incorporates plans for different time horizons, i.e. the business planning layer determines the planning that the operator must perform to ensure that the network will perform as required for its intended life span. The Operations and Maintenance layer, however, examines how the network will run on a day to day basis.

The network planning process begins with the acquisition of external information. This includes:

• forecasts of how the new network service will operate
• the economic information concerning costs; and
• the technical details of the network’s capabilities

It should be borne in mind that planning a new network service involves implementing the new system across the first four layers of the OSI Reference Model. This means that even before the network planning process begins, choices must be made, involving protocols and transmission technologies.

Once the initial decisions have been made, the network planning process involves three main steps:

• Topological design: This stage involves determining where to place the components and how to connect them. The (topological) optimization methods that can be used in this stage come from an area of mathematics called Graph Theory. These methods involve determining the costs of transmission and the cost of switching, and thereby determining the optimum connection matrix and location of switches and concentrators.
  
  
• Network-synthesis: This stage involves determining the size of the components used, subject to performance criteria such as the Grade of Service (GoS). The method used is known as "Nonlinear Optimization", and involves determining the topology, required GoS, cost of transmission, etc., and using this information to calculate a routing plan, and the size of the components.
  
  
• Network realization: This stage involves determining how to meet capacity requirements, and ensure reliability within the network. The method used is known as "Multicommodity Flow Optimization", and involves determining all information relating to demand, costs and reliability, and then using this information to calculate an actual physical circuit plan.
  These steps are interrelated and are therefore performed iteratively, and in parallel with one another. The planning process is highly complex, meaning that each iteration, an analyst must increase his planning horizons, and in doing so, he must generate plans for the various layers outlined above.