Seven ways to keep fiber migration on track and on budget

For most companies planning to build a high-speed backbone and extend fiber to the desktop, migrating from copper to a fiber network can be a smooth process...really.

BY CHERI PODZIMEK

For good business reasons, most companies are committed to building a high-speed backbone and extending it to the desktop. For many businesses, that involves migrating to fiber from an existing copper network. While this may seem intimidating, we've outlined seven strategies for success that can help make the process go more smoothly for you.

1. It's not all or nothing. Even if you ultimately want an all-fiber network, you don't necessarily need to upgrade all at once. Taking an incremental approach can help manage resources and upgrade in a targeted, planned way that saves money and reduces downtime.

As you upgrade different parts of your network to fiber, use media-conversion technology to provide a transparent link between the copper cable in the network and the fiber cable. Media converters can help bridge the gap economically, since they do not require new cable or the replacement of expensive equipment. With current pricing, it is not unusual for enterprise electronics equipped with copper ports and copper-to-fiber media converters to be less expensive than equivalent enterprise electronics equipped with fiber. And media converters are as easy to install as patch cables and connectors.

2. Keep your 850-nm electronics. Until recently, there was no seamless way to upgrade from 10 Mbits/sec to 100 Mbits/sec, even if you already had fiber installed. However, the soon-to-be-ratified 100Base-SX standard provides a migration path to Fast Ethernet using 850-nm light-emitting-diode electronics for distances up to 300 m. Eliminating the need to purchase higher-cost 1,300-nm electronics helps reduce your costs significantly and lays the groundwork for future migration to Gigabit Ethernet speeds.

3. Let auto-negotiation do it for you. Auto-negotiation is the mechanism by which two Ethernet/Fast Ethernet ports communicate with each other during the linkup phase of the connection. When two devices first connect, each one sends out a message (at the Auto-negotiation level, not an Ethernet message) stating its functionality.

Currently, the functionality in question is speed (10 Mbits/sec or 100 Mbits/sec) and mode of operation (full-duplex or half-duplex). The information is compared and the highest-performing combination is used. 10/100 auto-negotiation capability is fully supported by the 100Base-SX standard and found in network interface cards, switches, and even dual-speed hubs.

4. Centralize your electronics. Fiber-based architectures such as centralized cabling TSB-72 (which will be elevated to a normative annex with the imminent release of the revised ANSI/TIA/EIA-568B.1) offers you the ability to streamline network maintenance and reduce costs. This architecture leverages the high bandwidth and low attenuation of multimode fiber to centralize LAN electronics in one communications room within a building.

As a result, you do not need telecommunications closets (TCs) on every floor (reducing the number of active electronics), while making it easier for network managers to perform regular maintenance or troubleshoot problems. In some installations, the space assigned to TCs can be reclaimed-or minimized and used for other purposes.

5. Keep it small. Small-form-factor (SFF) connectors represent another significant factor that can reduce the cost of deploying fiber. Designed to cost less than traditional fiber connectors, SFF connectors have a footprint similar in size to copper RJ-45-style 8-pin modular-jack connectors. Because of their small size, SFF connectors can increase density and therefore reduce the cost of hubs and switches, lower patch-panel and enclosure costs, reduce jumper costs, and reduce connector installation costs.

6. Insist on quality products and support. The fiber market today is mature and well-populated with reputable suppliers that produce and stand behind high-quality products. When reviewing suppliers for your installation, ask them to show how their products have been used in similar installations and speak to other network managers who have deployed their solutions. Keep in mind that your choice of manufacturer is closely linked to your choice of installer, since only installers certified by that manufacturer can respond to your request for proposal.

To help you find manufacturers of fiber-to-the-desk equipment, the TIA Fiber Optics LAN Section (FOLS) posts a suppliers guide on its Website (www.fols.org).

7. Keep the future firmly in sight. When evaluating your upgrade strategy, make sure you look beyond your immediate needs five to seven years into the future. Careful evaluation of anticipated demands will ensure you build a solid infrastructure that will facilitate your network's future needs with minimal disruption and costs. Taking a "lifetime cost" perspective on your upgrade strategy helps balance and evaluate the differences between installed costs and lifecycle costs.

For many network managers, the prospect of minimizing the lifetime costs of their network is a compelling reason to deploy fiber when specific segments of their network need to be upgraded.

Fiber is not just a choice for new installations. The growing use of media-conversion technology, the introduction of SFF connectors, and the standardized solutions that have been developed to leverage the performance benefits of optical fiber mean that you can take advantage of fiber as you need it in your network-cost-effectively and cost-efficiently.

Cheri Podzimek is director of marketing at Transition Networks (Minneapolis). She wrote this column on behalf of the TIA Fiber Optics LAN Section (FOLS). Member companies include 3M/Volition, Allied Telesyn International, AMP Netconnect, Aura Networks, Belden Wire & Cable, Berk-Tek, CommScope, Corning, Corning Cabling Systems, Leviton Voice and Data Div., Lucent Technologies, Micro Linear, Ortronics, Panduit, the Siemon Co., Sumitomo Electric Lightwave, Sun Conversion Technologies, and Transition Networks. Visit the FOLS Website at www.fols.org.

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