For most companies, today's Wi-Fi is a wireless environment that drops signals, runs at speeds that remind you of an analog modem, is insecure and doesn't feature centralized management. In other words, it's a publically accessible data breach waiting to happen, while providing you only a bare level of usefulness. So maybe it's time to rip it all out.
Yes, I know that you need wireless access. After all, a wireless environment is very attractive since it allows great flexibility, makes adds, moves and changes very easy, and is dramatically cheaper than running cables. But the problem isn't wireless access -- the problem is YOUR wireless access. The reason is that most companies, probably including yours, installed their Wi-Fi infrastructure a few years ago, and at the time it worked well enough. Sure, there were dead spots in your building, but if you knew where they were, you could maybe avoid them. And it's true that some of your older access points and wireless routers used the old (and long ago cracked) WEP encryption, but there weren't any breaches that you know of.
Things have changed. A couple of years ago the Wi-Fi Alliance announced support for a draft of a new standard called 802.11n. This new standard operated on two frequency bands, the old 2.4 GHz band and the 5 GHz band used by 802.11a (which almost nobody used). The new draft supported a multiple antenna scheme that would take advantage of the reflections and multi-path problems that plagued earlier versions of Wi-Fi and use them to strengthen signals. And the new Wi-Fi routers and access points would support enterprise-grade encryption.
Now, the draft has been ratified by the Wi-Fi Alliance and products are on the market that are fully compliant with the standard. The changes are significant. Coverage is much better than it was with the old versions of Wi-Fi, speeds are dramatically higher (well over 100 Mbps for short distances), and even old Wi-Fi devices work better. Tests with a Cisco 802.11n wireless router that supports both bands simultaneously (it's the Linksys WRT610n) showed that older Wi-Fi equipment worked over longer ranges and were able to operate at higher speeds than previously. Tests with new 11n compliant devices showed dramatic improvements in range and throughput.
You can gain a significant improvement in your wireless environment by simply replacing your existing access points when it's time to upgrade them anyway, but in reality, it's probably better to speed up the replacement. It'll improve your productivity, your security, and it'll make life easier for your network managers and your employees, even those with old 802.11b and 11g laptops.
There are some things you should know, however.
The nice thing about a move to 802.11n is that you don't have to do everything at once. The new standard can coexist quite nicely with the old. But the improvements in your operations mean that you're missing out on some significant advantages if you don't move forward with an upgraded wireless infrastructure expeditiously.