Upgrading and Repairing Networks

Which Wireless Protocol Should You Use?

This chapter, as well as the preceding three chapters, was written to introduce you to the current wireless network standards. This chapter includes examples of 802.11g hardware installations because 802.11g is the prevailing standard for wireless networking. Even if you choose one of the enhanced 802.11g standards discussed earlier in this chapter, configuration of APs and servers using faster or longer-range technologies is similar.

You have a variety of choices to make in the current marketplace:

• Standard IEEE 802.11g wireless hardware

• Dual-band IEEE 802.11a/802.11g wireless hardware

• Dual-mode IEEE 802.11a/802.11g wireless hardware

• Enhanced-speed versions of IEEE 802.11g

• Enhanced-range versions of IEEE 802.11g

If you are satisfied with the performance of IEEE 802.11g, plan to use it at ranges of no more than about 50 feet between the furthest client and an AP. Especially if you are building on an earlier IEEE 802.11b wireless network, standard 802.11g network hardware is the least expensive choice, and a good one for most users. It enables seamless interconnection of 802.11b and 802.11g clients, whether they use USB, PCI, CardBus, or integrated adapters.

If you need to support 802.11a clients as well as 802.11g or 802.11b clients, select a dual-band 802.11a/g AP. Dual-band 802.11a/g clients are useful primarily if the computer will be moved between networks based on those standards.

To improve performance on a network that uses both 802.11a and 802.11g clients, use a dual-mode AP and configure it so high-bandwidth traffic runs on the 5GHz 802.11a frequency and lower-bandwidth traffic uses the 2.4GHz 802.11g/b frequency. To get the maximum benefit from dual-mode networking, you might need dual-mode clients.

If you need 30% faster speed than standard 802.11g, consider one of the enhanced-speed 802.11g solutions detailed in Table 21.2. For best interoperability with existing hardware, choose an AP that uses a chipset from the same vendor that your existing clients use. Generally, a wireless vendor uses the same chipset vendor for various product lines. If you need greater range, especially for a campus environment with a large outdoor space, and you're building your network from scratch, consider a MIMO solution from those listed in Table 21.3. If you need to boost the range of an existing network and don't want to replace your APs or client adapters, consider replacing your AP's standard antenna with high-gain versions.

Keep in mind that security can be the weak spot in wireless networking. By nature, a wired network is still more secure than a wireless network. If you decide to build a new wireless network or add to an existing one, make sure your wireless network supports, at a minimum, WPA security.

	For more information about WPA and other types of wireless security, see "Wireless Security" in Chapter 23, "Security and Other Wireless Technologies," p. 349.