Deploying 802.11n

Once you have decided to jump on the 802.11n bandwagon, there are several decisions to make that can impact the success of the installation. Although 802.11n promises to be bigger, better, and faster than existing wireless technologies, “easier to install” is not a phrase I would use.

Access Point Placement
The importance of access points (AP) placement for complete wireless coverage across your organization is something that doesn’t fade with the new standard. In fact, you’ll find there are new challenges, as an article on deploying 802.11n explained:

“On average, enterprises spend 15% to 20% of their entire WLAN budget on planning and AP placement activities. This is important to keep in mind because – with the new standard’s use of MIMO technology – planning can be much more challenging than with previous Wi-Fi standards. While MIMO helps extend the wireless range, it also creates islands of wireless connectivity, making it challenging for the networking manager to design the network.

But planning doesn’t have to be difficult or time-consuming. Each vendor is recommending different approaches to planning and placement. Vendors with a fourth-generation architecture have been identified by Gartner as offering the easiest deployment and simplest site planning because they are more immune to interference issues and can operate with fewer, non-overlapping channels.“

Upgrading Existing Infrastructure
Upgrading to 802.11n may mean that you upgrade the rest of your WLAN infrastructure to take full advantage of 802.11n and to adequately support higher traffic volumes that will be generated. Will your WLAN architecture support the higher traffic volumes that will be generated?

Tim Scannell outlined the bandwidth and security issues that could affect networks relying too much on existing infrastructure:

“The latest wave of products based on the still evolving technology can deliver access speeds up to 30 times faster than most existing Wi-Fi networks. When pared with multiple-input multiple output (MIMO) antenna technology, 802.11n can also have a much farther reach and signal strength than conventional Wi-Fi.

The more robust nature of 802.11n systems can overtax controllers that may not be able to keep up with the increased networking traffic flow. Security may also be an issue if wireless activities are shifted away from the controller and to the access points (AP) without installing the proper safeguards at these edge points.“

These are some of the issues to be aware of when rolling out new 802.11n wireless products. The deployment should be similar to past wireless deployments. It’s not something you’re going to rush into, rather you should test out the technology with a smaller deployment, conduct a wireless site survey, check for interference, and get the kinks worked out before going network wide.

Two articles that I found extremely helpful:

802.11n Deployment Issues - SearchNetworking.com
Deploying 802.11n? Consider Existing Infrastructure - Enterprise Networking
Wireless Monitoring - Network Instruments