Try these five tips for squeezing a long life from infrastructure investments.

If you've ever done a tricky remodelling project at home, you might be familiar with the urge to just level the place and start over. But on your corporate network, no one wants to have to explain the need for a forklift upgrade where large parts of the infrastructure must be overhauled. How can you maximise the longevity of your IT investments in a world of ever-changing protocols and constantly evolving security dangers? Beyond thinking carefully about scalability and capacity, here's a look at some key tasks for your future-proofing to-do list. Keep these considerations in mind as you evaluate and purchase new gear.

1. Stick to modular equipment, centralised management.
To avoid rip-out upgrades later, follow this advice whether you're planning your wireless or wired LAN. On the wireless side, this usually means buying a centralised wireless LAN (WLAN) switch that will let you upgrade access points easily. "Standalone fat [access points] exclusive architectures are out, but some companies are deploying a mix of thin and thick," for example, using thick access points to support branch-office locations, says Ellen Daley, principal analyst at Forrester Research. On the wired side, this means selecting equipment that is as modular as possible in the wiring closets and the core data centre. Even then, consider keeping about 20 percent of the expansion room open.

With management tools, the fewer pieces you have to snap together, the better. "Ensure that you are managing your WLAN network like you manage your LAN . That means centralised help desk support, centralised management tools, and a clear support website," Daley says.

2. Navigate the wireless standards waters.
Are you waiting for a set list of wireless standards before doing any more WLAN planning? Bad news: You can't wait that long. These standards - such as the up-and-coming 802.11n for higher bandwidth, 802.11r for fast roaming, and 802.11e for QoS - will remain in flux for a while. "802.11n is coming, but given the standards fight going on, don't plan to wait for 802.11n. It may be a few years before there is ratified equipment," Daley says.

However, knowing how vendors address fast roaming and QoS is important. At minimum, you want to stay below 50 millisec for roaming between access points. For QoS, confirm that your vendor supports the Wireless Multimedia standard, or will shortly. Also, make sure the vendor can articulate how it will make products compliant with the future 802.11r and 802.11e standards, and any associated costs, Daley says.

3. Make way for 10G and avoid bottlenecks.
In the Gigabit vs. 10 Gbit/s Ethernet debate, how should you play it smart? "Prices are still pretty high," says David Newman , president of Network Test, a benchmarking and network design firm, and a member of the Network World Lab Alliance. But playing it cheap might not be prudent if your current backbone can't keep up later.

"10G is the automatic choice today in data centers. The place where it's time to start thinking about it is the wiring closet," he says. Current wiring closet switches have one or more uploads to the corporate backbone; today that's Gigabit, but we're starting to see boxes with 10G uplinks. Remember, virtually every new PC now has a 1G bit Ethernet adapter included, Newman says. Put all these PCs on your network and you're putting a heavy burden on the backbone. "With 10G, you're not going to have bandwidth bottlenecks. Plan today and avoid congestion," he says.

4. Keep an eye on new Ethernet specs.
While new Ethernet specifications continue to pop up, many of them pertain to switching and security aimed at service provider networks. The one that could be an intriguing option for the enterprise LAN is 802.1AB, or Link Layer Discovery Protocol (LLDP). You'll see this mostly in switches, routers and IP telephones, though you won't see it often, for now. This discovery protocol helps a switch learn about an endpoint device such as a VoIP phone and helps simplify configuration.

Extreme Networks recently introduced the first edge switch with LLDP capability, and Extreme's telephony partner Avaya plans to introduce LLDP-compliant phones later this year. LLDP could make VoIP rollouts more plug-and-play, and simplify policy management. LLDP's network troubleshooting and management possibilities might widen, but you'll have to wait and see whether more vendors implement the technology in edge switches.

5. Cross IPv6 off your worry list - mostly.
Next-generation IPv6 makes important improvements. But should you be investing in it today? "It's not that important [in North America] yet, with two exceptions," Network Test's Newman says.

The first exception: Asian companies with local operations or local companies with Asian operations. In Asia, branch offices, customers and suppliers already are building and using IPv6 networks. If this describes your company, don't wait to create a deployment plan, Newman says. In the other exception, the US Department of Defense has committed to IPv6, so its would-be contractors need IPv6 on their radar screens.

Otherwise, you can wait. "There's no compelling driver for a small or medium business to go to IPv6 today," Newman says. But do look for IPv6 support in the routers you buy, he advises. "The potential you're going to need that v6 support is only going to increase over time."