Cabling Systems and Network Performance

Graybar technology professionals and corporate executives are concerned, and rightfully so, about network performance. Bandwidth has been described as the currency of the next decade—those that have it, and can utilize it most effectively, will deliver critical business applications to internal and external customers before their competition and gain a competitive edge. Doing so cost effectively will determine the winners.

As networks continue to evolve, expand, and increase in speed exponentially, traffic analysis tools are a critical component to network management. All major switch manufacturers include network management functions with their core products, to analyze each port's utilization, errors, and other key statistics. Using these permanent monitoring tools is the only way to track data on all ports, and obtain a complete understanding of what is happening on a network.

Network management software including, CiscoView by Cisco, and Transcend from 3Com, are available to present the traffic statistics graphically at a fraction of the per-port costs of other tests requiring special external monitoring devices. Many of today's newest switches allow the network manager to display these statistics, and administer the device from a standard web browser such as Netscape Communicator or Microsoft Explorer. All these tools can be utilized to monitor data on all ports, or on a port by port basis. The Graybar is gathered and passed from the switch to the network management station using SNMP and RMON. Monitoring traffic this less intrusive way does not require a connection that will actually alter traffic patterns as it attempts to measure them. Handheld test units, like the 68x series of products from Fluke, provide trouble shooting capabilities to analyze traffic identified through the switch to provide customers with the network performance they require.

Claims that the cabling system must be designed specifically for a generation of electronics have been outdated since the TIA-EIA standards provided the market with guidelines. The "If you don't install my proprietary cabling system" tactics have long fallen on deaf ears. The IEEE sets guidelines for the development of products, which are based on cabling systems designs that induce minimal losses. Loss budgets have been incorporated into product development for fiber and copper networking for years. To protect our customer's investment in time and business efficiencies, cabling systems should be designed to support multiple generations of electronics, since cabling upgrades are so disruptive to the work environment. That is one of the reasons we developed the VIP Program, which requires independently verified channel performance beyond the TIA standards.

The concept that a standards compliant cabling system would induce loss that is unacceptable for electronics is not based in fact. The fact that not all cabling system components perform the same with other components is the truth. That is why with the VIP program, Graybar and ITS-ETL verify the performance of cabling systems, so you know that what you buy, will perform. Many segments of new installations will not be used at full network speeds for years. But our VIP laboratory test, with field verification program, gives you the option to check your installations' readiness, without the electronics installed.

Deterioration in network performance is usually attributed to changes made after the network installation. The most common change is, on a network segment, the number of users goes up. With these additional users, the performance of the network goes down. What role does a properly installed, VIP compliant cabling infrastructure play in this? NONE. Not segmenting the network adequately and insufficient backbone provisioning create many of the problems.

As desktop workstations get faster, and we migrate to faster network connections, the network backbone must be sized correctly to accommodate the increased traffic. A commonly used sizing technique is to implement backbones with at least 10 times more bandwidth than the port speed of the switch it is serving. Customers running Fast Ethernet to the workstation should be installing at least One-Gigabit backbones. This is why we will release our VIP Fiber program, to provide sufficient backbone bandwidth, later this year.

Verifying performance claims through an independent testing organization is the best way to assure products meet the claims of manufacturers. Look for independently verified solutions to protect your investment, and to identify the best products available.

Written by: *Rob R. Bezjak, RCDD and Russell Ost, RCDD

* Rob, is a National Market Manager based at Graybar's corporate headquarters in Clayton, Missouri.

** Russell is a <%=company%> Network System Specialist, with his Cisco CCNA and CCDA, based in San Jose.