The Role of the Network Designer

Prior to taking a look at the various tasks involved in designing a network infrastructure, it’s important to be familiar with the role that a network designer or architect plays. Although the exact responsibilities that a network designer will take on for the duration of a specific project can vary based on the size or scope of the undertaking, common themes apply to almost all projects.

Certainly most network designers start their careers on some network engineering-related path; foundation knowledge and hands-on experience in these areas is critical. However, the main goal of a network design professional is to map an organization’s main business and technical goals to a functional network design that meets all stated needs. In some cases this can be a relatively simple undertaking, but in many cases, the process is much more complex. On a typical network design project, the designer handles roles that include needs analysis, data gathering, producing documentation, designing an appropriate solution, overseeing implementation, troubleshooting, verification, and more.

Quite simply, network designers wear many hats; they not only have to be able to effectively determine the true business and technical requirements driving a project, but also deal with a range of non-technical issues including personnel, politics, scheduling, and even “selling” their concept. At the end of the day, however, a good network designer will still be able to roll up their sleeves, get in there, and configure equipment if necessary. Their approach may seem very high-level in some ways, but a thorough understanding of how systems function, interrelate, and are configured is equally crucial.

Protocol Analyzers and Cable Testers

A protocol analyzer is a software utility that allows network traffic to be captured, and the contents of frames to be analyzed. A protocol analyzer often provides the best point of reference with respect to communication issues and errors that may be occurring on a network. The capabilities of protocol analyzers vary greatly, and range from enterprise products like Sniffer from Network Associates, to freeware tools like Ethereal.

A cable tester is a small handheld hardware device that can be used to troubleshoot a variety of physical connection and cabling issues. For example, a cable tester can be used to determine whether the pinouts of cables are correct, whether maximum distances have been exceeded, if a cable contains breaks, and so forth. Cable testers are available for a variety of different media (twisted pair, coax, fiber) and tend to be an invaluable resource in when troubleshooting physical layer issues.

Cisco FastStep

Cisco FastStep is another free Windows-based utility that helps users configure, troubleshoot, and monitor selected Cisco routers. Aimed at the small office and home market, this wizard-based tool walks inexperienced users through the configuration of connections to an ISP and/or a corporate network. The product also allows more advanced features (such as DHCP or NAT) to be configured through the wizard interface, depending on the IOS version included with the router. Once configured, another utility called FastStep Monitor provides the ability to monitor router interfaces, and generate email alerts when something goes wrong.

FastStep is only provided for certain router models, including those in the 700, 800, and 1600 series, and the 2509 and 2511 models. The tool is included on a CD with those models, or can be downloaded from the Cisco website.

Cisco ConfigMaker

Cisco ConfigMaker is a great free utility that allows Cisco routers, switches, and hubs to be configured from a graphical application that runs on Windows. The drag-and-drop interface allows you to create a “map” of your network (including links), and then access the properties of devices to complete their configuration. The tool doesn’t require any knowledge of the Cisco IOS command line interface. Once complete, the generated configuration files can be uploaded to devices via their console port, or over the network.

The ConfigMaker tool is aimed at small and medium businesses, as well as Cisco resellers. Routers that can be configured with the tool include those in the 800, 1000, 1600, 2500, 2600, 3600, and 4000 series.

Cisco Netsys Baseliner for Windows NT

Rather than generating network views using SNMP (as is the case with most network management applications), Cisco Netsys Baseliner for Windows NT generates a view of your network using the actual configuration files from existing Cisco network equipment. This provides you with a complete view of the network, including both the physical and logical relationships between devices.

After Netsys Baseliner has created a model of the existing network, it uses an offline version of this model to test for configuration errors. The application also allows you to make changes offline for testing purposes. This provides the opportunity to see what impact any changes may have, before they are committed to the live network. Cisco Netsys Baseliner is currently an End-of-Life product.

Cisco Netsys Performance Service Manager

The Cisco Netsys Performance Service Manager tool is also part of the Cisco Netsys Service-Level Management Suite. Capabilities found within the program include the ability to manage network performance service levels, define performance policies, and troubleshoot performance-related issues. Like the Connectivity Service Manager tool, this tool also builds a view of the current network topology using information stored in the configuration files of deployed equipment.

This tool gathers data in a number of ways, including using SNMP and RMON performance data from network switches and routers. This data provides the ability to visualize network performance in real-time, or to create a baseline measurement against which future changes can be compared, both through “what-if” analysis and actual implementations. Baseline data can also be used to develop service-level policies against which regularly collected data can be compared via a difference mechanism. Tools within the Cisco Netsys Service-Level Management Suite are mainly aimed at larger networks, where service-level agreements have been defined and need to be measured.

Cisco Netsys Connectivity Service Manager

The Cisco Netsys Connectivity Service Manager tool is part of the Cisco Netsys Service-Level Management Suite. The product is focused on providing information that allows you to troubleshoot a variety of network connectivity issues. The application builds a map of the existing network using the configuration files of existing Cisco devices, and subsequently allows you to use this information to troubleshoot issues relating to network availability, security, and reliability.

Capabilities found in the application include the ability to view different topologies, such as the physical or logical connections between equipment. Taken a step further, protocol views are also provided, for example the ability to view OSPF areas and interconnections. The application also helps in determining the source of network errors, including those related to access lists, mismatched frame types, incorrect subnet masks, and so forth. Positioned as a tool to help companies move towards a proactive management strategy, the Netsys Connectivity Service Manager also provides extended capabilities such as offline “what-if” analysis by way of the VISTA (view, isolate, solve, test, apply) troubleshooting methodology.

Note: All of the software in Cisco’s Netsys line has reached end-of-life (EOL) status.