Chapter 14: Network Planning and Design Tools

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14.1 Introduction

Today’s networks are more complex by orders of magnitude than networks built only a few years ago. New Internet services, technologies, and trends toward VPNs, voice-data convergence, and wireless, plus the sheer number of new equipment offerings, have made reliance on traditional paper-and-pencil solutions to network documentation and design simply unworkable. Intelligent design tools with auto-discovery, error-detection, simulation and analysis capabilities, and plug-in modules for ancillary functionality are now the norm.

A typical corporate network consists of different kinds of transmission facilities, equipment, LAN technologies, and protocols—all cobbled together to meet the differing needs of workgroups, departments, branch offices, divisions, subsidiaries, and, increasingly, strategic partners, suppliers, and customers. Building such networks presents special design challenges that require comprehensive documentation and design tools.

A variety of automated design tools have become available in recent years. With built-in intelligence, these tools take an active part in the design process, from building a computerized model of the network, validating its design, and gauging its performance, to quantifying equipment requirements and exploring reliability and security issues before the purchase and installation of any network component. Even faulty equipment configurations, design flaws, and standards violations are identified in the design process.

These tools are especially valued by IT departments experiencing high staff turnover because they allow new personnel to become familiar with the details of the network they played no part in designing and managing. The essential information can be retrieved on a moment’s notice—often with point-and-click ease— analyzed, queried, manipulated, and reanalyzed if necessary, with the results displayed in easy-to-understand graphical form or exported to other applications for further manipulation and study.

Network documentation and design tools are often purchased as separate applications, but each contains some of the functionality of the other. For example, both types of tools feature drawing capabilities and come with libraries of equipment shapes that can be linked together. But a documentation tool excels at documentation and is not so adept at design to the point of alerting the user to standards violations, for example. Likewise, a design tool excels at design and is not so adept at allowing users to add descriptions of equipment, lines, and services in the detail they often need.

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