You've been thinking about Gigabit Ethernet for a long time now, haven't you? Perhaps you've even installed some server-to-server gigabit network links, although price tags of over a grand per port have likely kept you from deploying it to the desktop. That was then, this is now.
Today, you can get gigabit switches at prices that drop the single port cost to less than $100. At that price, you can afford gigabit not just on the server farm, but all the way to bandwidth-hungry users as well.
Of course, you don't want to drop gigabit to everyone in the company. While the price per port may be affordable, there are other factors to consider. First, you may need to replace your cable. If you upgraded your wiring plant recently, you may already have Cat 5, the minimum for gigabit, installed. On the other hand, if you last touched your cables in the mid-'90s, you probably still have Cat 3. In theory, Cat 3 is only capable of supporting for 10Mbps Ethernet, although in practice, people have often forced 100Mbps Fast Ethernet to run over it -- well, sort of run over it. Ideally, you'll want to use Cat 5e or Cat 6 cabling, since Cat 5 really is a minimum (the same way that 128MBs of RAM is a minimum for Windows XP Professional).
Additionally, the vast majority of PCs aren't fast enough to deal with gigabit Ethernet. A run of the mill cheap bus in a computer only runs at 133MBs per second, which is nowhere near fast enough to take advantage of gigabit's speed. Newer computers using faster buses with 800MHz speeds, such as those based on Intel's 875P chipset (aka Canterwood), can, in the current generation, deliver peak bandwidth in the 4.2GB range. That's more than fast enough to deal with gigabit Ethernet. In your servers, you may already have PCI Express (PCI-X), once known as "Third Generation I/O" (3GIO), buses. These can handle one GBps, so they're more than up to the gigabit Ethernet challenge as well.
Still, the bottom line is that you're almost certainly going to need your upgrade your client PCs if you really want to enjoy gigabit's speed benefits. If you can't, while gigabit Ethernet will deliver a performance boost of about 30% over Fast Ethernet on standard Pentium III and higher computers, it's not really cost effective since Fast Ethernet ports cost only a third of gigabit Ethernet's ports. While gigabit's much cheaper than it used to be, so is Fast Ethernet.
You should also be wary of computers that come with combination 10/100/1000 network interface cards (NICs). Just because the PC has a gigabit NIC under the hood doesn't mean the bus will actually fully support that speed. Buyer beware: if you buy PCs to use gigabit Ethernet, make sure the bus is PCI-X, 875P, or another high speed design. Just like computers with integrated graphics sound like a good deal, users who need top performance will ultimately find them disappointing.
The Bottom Line on Gigabit Ethernet
The bottom line is that if you really want to cost justify pushing gigabit Ethernet to the desktop, you're almost certainly going to need to upgrade your PC base as well. If that's out of the question, you're probably better off waiting until your next PC mass upgrade and then putting gigabit in. But if you can afford to upgrade your client machines, putting in gigabit Ethernet makes a lot of sense...for some users. Even with today's low network and PC prices, there's simply no justification in bringing gigabit Ethernet to receptionists, typists, and the like. Instead, you should focus on the people who really can use it.
And exactly who are these people? The answer, as always, is to look at the applications and which users are utilizing the most bandwidth-intensive software. For example, if you're using desktop video conferencing, the executives who actually use it should get gigabit. Other areas that will almost certainly benefit from gigabit are those who regularly work with desktop publishing (DTP), CAD/CAM, accounting analysis, database analysis, or graphics software.
The performance difference for these users can be dramatic. For example, a PhotoShop 6 image that takes tens of seconds to come up on Fast Ethernet can pop to the screen in a second using gigabit Ethernet. When your massive data file users make frequent saves, the collective time savings can add up to more than an hour a day -- an impressive time and productivity savings no matter how your overall return on investment turns out.
As for the gigabit switches, you need to look for more than just maximum bang for the buck. A switch may offer you cheap ports, but if it delivers TCP/IP switching in software instead of via the application-specific integrated circuit (ASIC), you've got a switch with a built-in performance problem.
You should also look for features such as authentication server support that work with your existing authentication framework. 802.1q and 802.1p support, which respectively provide Virtual LAN (VLAN) and Layer 2 network traffic prioritizing for quality of service (QoS), are also important. And, as always, you'll want network management controls that you're comfortable with. Many switches, for example, now come with easy to use HTTP-based web interfaces, while others require you to know your way through a telnet character interface.
Concerns and all, though, one thing is definitely clear -- at these prices, it's time to get ready for gigabit Ethernet. Perhaps you can't afford it this year, but as PC speeds increase and users work with bigger and more data-intensive projects on their desktops, you can count on demands for gigabit next year in data-intensive departments like engineering and DTP. And while the preceding concerns or the current economy may not afford you the opportunity to implement gigabit right now, it's certainly time to start planning for its imminent arrival.