Traditional wireless LANs make use of relatively intelligent access points. Learn the benefits of deploying a newer “thin” access point approach.

The access point, which interfaces wireless client devices to a wired network, is the primary component of a wireless LAN. A company installs multiple access points to provide coverage throughout a facility, enabling users to roam. The radio card in the client device conforms to the 802.11 (Wi-Fi) standard when performing medium access functions, associating with access points, and carrying on the transfer of data packets.

The Traditional “Thick” Access Point Approach

Most access points, especially those for enterprises, traditionally have intelligence beyond what the 802.11 standard provides. For example, an enterprise grade access point will implement advanced functions that enhance security, management, and performance. For example, an access point incorporates sophisticated access control mechanisms to afford better security than what the 802.11 standard contains.

These “thick” access points tie to conventional Ethernet switches in an enterprise and provide a wireless LAN backbone infrastructure. The switches in this case don’t usually have any features that enhance wireless communications, however, such is necessary when supporting voice over wireless LANs.

These traditional enterprise grade access points are relatively expensive as compared to the “thin” access points that I’ll discuss later. As a result, it’s costly to scale up the wireless LAN when installing additional access points to increase coverage or performance.

In addition, the “thick” access point approach is costly to migrate to newer technologies. In some cases, a company can merely upgrade the firmware of the access point to begin implementing modifications, such as WPA. The deployment of some technologies, such as AES, will likely require replacing the access points. Consequently, the “thick” access points can be expensive to support.

Also in regards to support, “thick” access points have lots of configuration parameters that operational support software must interface with. This places a significant amount of over head traffic over the network, which can decrease available throughput for primary applications.

“Thin” Access Point Solutions

Some wireless LAN manufacturers, such as Legra and Airespace, minimize the intelligence in the access points and employ a central wireless switch. This centralizes the intelligence in the switch instead of the access points. With this approach, the relatively simple access points can share the features that enhance wireless communications in a cost-effective and efficient manner.

Because the “thin” access points don’t implement much more than the 802.11 standard, they are generally less costly. This can reduce the total cost of ownership of a wireless LAN because of less expensive upgrades and migration to future technologies.

Much of the configuration is centralized in the wireless switch, which reduces management functions from operating over the wireless LAN. An administrator can interface directly with the switch from the more familiar wired side of the network. The central nature of the switch makes it an excellent platform for managing the network.

In addition, the wireless switch optimizes performance. Roaming handoffs are much faster than conventional switches, which makes it more practical to effectively support voice over wireless solutions.

Some Final Thoughts

If you’re deploying a wireless LAN, strongly consider the use of the “thin” access point solution that makes us of a wireless switch that enhances operation of the wireless LAN. Before making a decision, though, compare the total costs of both approaches. Just don’t forget to factor in changes that will likely need to occur to the wireless LAN. A very high percentage of companies expand the network once requirements are better understood. With that in mind, the “thin” access point solution shines.

 Jim Geier is an independent consultant and founder of Wireless-Nets, Ltd (www.wireless-nets.com), a consulting firm assisting municipalities, enterprises, hospitals, airports, and equipment providers with the development and deployment of wireless networks.