NETWORK DESIGN

Network Design

Network Design

Introduction

A corporate or enterprise network is one of the most important additions to corporate environments of the past decade. It serves as a way to meet the ever increasing needs for dispersed business operations. Furthermore, telecommunication has become a radical force of change in the corporate environment. The massive deployment of corporate networks can transform the corporation in several ways, providing competitive advantages, including innovative method of marketing and customer service, as well as allowing restructuring and downsizing with vertical disintegration .

A corporate network is a companywide communication platform. It accesses offices and buildings beyond those which could be connected with local area network (LAN) technology. Therefore, a corporate network can be viewed as an internet and each of the constituent networks is a local subnet. These are connected by intermediate systems (ISs) such as bridges and gateways .

The interest in such a distributed configuration has become increasingly important, partly because of technological advances in data communication coupled with major distributed information processing needs. A corporate network allows internal corporate communication, such as electronic mail (E-mail), computer conference systems (CCSs), electronic information services, and groupware. Furthermore, it may be connected with external networks. The popularity of these networks in today's enterprise information processing services makes their management increasingly important. The enterprise, large or small, has made significant investments in its networking services, and it is likely that organizations will continue to need further investment in these networks.

The objective of network management is to maximize the efficiency and productivity of the network. This involves five functional areas: performance management; fault management; configuration management; security management; and accounting management (e.g. see ). The emphasis of this paper is on performance management: the first step in ensuring that the network remains accessible and effective. Thus performance management is a topic of interest to researchers .

Corporate network system evolution is important. While replacing stand alone applications with corporate networks enhances system reliability and flexibility, it may lead to a 'creeping escalation' : incrementally adding and disposing equipment results in expansion. Although an individual installation may be reasonable, the totality of installations throughout the enterprise may well exceed the overall requirements. Therefore, an integrated control mechanism is necessary. Furthermore, managing a network usually involves a variety of tasks, but their interdependency has frustrated many practitioners.

This paper proposes a framework for guiding the performance management of corporate network systems. Two primary components are addressed: a life cycle for managing user performance with a transaction delay model.

A network design problem can be decomposed into two main parts, i.e. the access network design problem and the backbone network design problem. Typical network topology could be shown in Fig.

Fig. Typical network topology (backbone+ access network).

In Fig. 1, we could see that the backbone network which is connected by the backbone router is usually a mesh topology for reliability concern. In designing an access network, a number of topologies may be selected, e.g. tree, mesh and star. However, the following two trends will strongly affect the access ...