How It Works: Ethernet

Ethernet Comes Down to Earth

Ethernet, the most common form of networking, is used in the vast majority of businesses with networks. Thanks to its widespread adoption, you can find dozens of products that you can use to piece an ethernet network together.

Each computer on the network needs a network adapter, which provides the link between ethernet and the PC. Many PCs sold today offer add-in network cards as an option, and a few offer integrated network ports. If you own a computer without one, you can purchase a network interface card from companies such as 3Com and Linksys. NICs come with PCI, ISA, and Universal Serial Bus interfaces. The cards range in price from $15 to more than $150, depending on the card's features, though most people can use the least expensive card that supports their network's top speed. All NICs can talk to one another.

Supporting that top speed is important: If you have a 10Base-T setup but intend to upgrade to 100Base-T, it makes sense to buy an autonegotiating NIC--one that can run at either 10 mbps or 100 mbps. You'll still need to add 100 mbps hubs and possibly new cabling to bring the network up to speed. Adding a PC Card or Card Bus NIC ($40 to $150) to a notebook computer will make it ethernet-ready.

If you're connecting more than two PCs, you'll need a hub. Hubs from such companies as D-Link, Intel, and NetGear vary in price, depending on their throughput and how many computers they can handle. For example, a 5-port, 10Base-T hub from 3Com or Intel costs about $40, while a 16-port autonegotiating hub from Linksys costs $200. Alternatively you can opt for a switched hub; prices for these begin at $100 for D-Link's five-port, 10/100Base-T model. Switched hubs can handle more network traffic and are the stronger choice if you plan to grow the network.

Shopping around for inexpensive components can save you money but not the headaches of setting up a network for the first time. If you're new to networking, you can buy all-in-one kits instead of piecing together products from different vendors. 3Com, Linksys, and NetGear sell kits that include everything you need: NICs, a hub, and wires. Aimed at small- and home-office users, the least expensive kit ($60) provides connections for two PCs. Larger configurations, such as kits that connect ten PCs, cost about $2000.

In addition to the hardware, you'll need an operating system that supports networking; most versions of Windows support it, beginning with Windows 3.1 for Workgroups. Make sure you can get NIC drivers for the operating system you use, and note that finding drivers for Windows NT, Windows 2000, and Linux may be difficult.

As more people bring home second and third PCs, demand for home networking solutions is growing. Analysts say ethernet is often the best solution for small businesses, but home users may want to explore the alternatives: specifically, phone line and wireless networking. Phone line kits, such as S3/Diamond Multimedia's HomeFree, can send data at 10 mbps using existing home telephone lines, without disrupting regular phone conversations. Wireless networks transfer data at up to 11 mbps using radio frequencies that pass through walls. But wireless networks such as Proxim's Symphony cost more than either ethernet or phone line networks, at about $100 per adapter, making them hard to justify for many home users.

Additional Resources:

• Charles Spurgeon's ethernet site
  
  
• Lantronix's ethernet tutorial
  
  
• The Ultimate Guide to Networking
  
  
• The Webopedia's entry for network