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10/100-Mbps NICs and workgroup 100-Mbps hubs are the white bread of fast networking technologies--they're cheap, they're available from just about any vendor (see for yourself in the Buyer's Guide charts beginning on page 182), and they get the job done. If you ar en't already enjoying 100-Mbps networking, you won't find a better time to make the switch.

In the past, one of the biggest hurdles network managers faced was figuring out how to get more than 10 Mbps to the desktop. Until recently, FDDI and ATM were the only--and very expensive--choices. Today, Fast Ethernet has emerged to fill in that steep price pothole. Fast Ethernet is cheap and simple to implement.

Most of us are still using a 10-Mbps shared Ethernet network or Token-Ring. These might be just fine for now, but change is inevitable and necessary. For example, lots of real-time video-related applications will choke on a 10-Mbps shared Ethernet network. So, go ahead, eat your old network for lunch and start taking advantage of 100-Mbps networking.

Steak With All the Fixins'? Sure, ATM and Gigabit Ethernet provide transmission speeds far faster than 100 Mbps, but each has its drawbacks. First, ATM and Gigabit Ethernet don't hit the price sweet spot that would make them widely deployab le. Furthermore, ATM is dead outside of the wiring closet; it has no life beyond the backbone of your network. ATM NICs are expensive, and most users want to make use of the Ethernet hardware already built into their desktop machines. If ATM does manage to make it out of the closet, it's still most commonly used as a connection to Ethernet edge devices and enterprise servers.

As for Gigabit Ethernet, it's still fairly far out on the bleeding edge, and only now starting to be used by the speed elite as they wait for it to become a standard.

Start With the Basics: Appetizers You need to know about two Fast Ethernet standards: 100BASE-TX and 100BASE-T4. The former uses two pairs of Category 5 copper wiring, while the latter requires four pairs of Category 3 copper wiring.

If you plan to use 100BASE-TX and have CAT 5 wiring pulled, all you need do is add hardware. On the other hand, if you plan to use 100BASE-T4 because you have CAT 3 wiring, you may hit a few snags. Many sites with four pa irs of CAT 3 wiring in the walls use the second set for telephones or additional Ethernet connections. If you're at this point, it's time to string CAT 5 wiring. Otherwise, if the majority of your wiring is four-pair CAT 3, and it's all available, consider 100BASE-T4.

But before you run off to buy 100-Mbps hubs and NICs, be sure your wiring plant is up to the task. If you know that an upgrade will be necessary, CAT 5 UTP (unshielded twisted pair) seems to be the soundest choice. It supports data rates (not including Gigabit Ethernet) up to 622 Mbps over some respectable distances, it's easy to terminate and run, and the jacks and connectors used with it are inexpensive.

Between wiring closets, and particularly in building risers, fiber is a must. It's more reliable and is immune to electrical problems that often present themselves when wiring taller buildings.

With desktop connections, simply installing CAT 5 wire does not make the end-to-end circuit CAT 5-compliant. Extra care must be given to ho w the wire is installed, the length of wire runs and the connectors and connecting methods used to terminate the wire ends. There are nine important areas of concern when installing CAT 5 wire: minimum bend radius; pulling and handling methods; jacket removal; untwisting of pairs; maximum length; patch and jumper cord assembly; electrical interference avoidance; termination methods; and final testing procedures.

To download an Adobe Acrobat .pdf format version of the 100-Mbps Hubs Buyer's Guide charts, click here.

To download an Adobe Acrobat .pdf format version of the 100-Mbps Nics Buyer's Guide charts, click here.