Guide to WLAN Management
Buying tips: It's all about future-proofing your netBy John Cox
We polled a group of users, analysts, and Network World Clear Choice testers Tom Henderson and Joel Snyder for tips on what WLAN management gear to buy and how to buy it.
Some of the tips are applicable to most IT purchases. For example, when dealing with small or young specialty vendors, verify to the degree possible their financial health. This is tough with privately held companies, but you can look at "vital signs": what existing customers say about technical support quality, whether planned updates arrive on time or arrive at all, whether their customer contact reps have been stable over time or whether there's been churn.
Another is to compare the management functions and features of each vendor in-house, as far as you can. It's like comparative test drives for your next car. A checklist only takes you so far.
Some are obvious but still important: Make sure the management software will support your specific WLAN equipment, your net topology, and its planned or expected growth and changes. The clearer you are about your specific network requirements and service-level agreements, the clearer are a vendor's product and service strengths and weaknesses.
The shift to the high-throughput 802.11n standard is coming in 2008 and 2009. Find out what the vendors plan for specific, new net management features and changes to support it.
Effective WLAN management needs to connect to existing back-end net infrastructure components, such as directories, authentication, security and performance monitoring, Henderson says. Find out how and to what degree the management software makes these connections.
Bear in mind that wireless LAN management has distinct, separate components, Snyder says. Some vendors attempt to offer all. Others offer some, and sometimes partner with other vendors for the missing pieces. Evaluate each component and how well, or whether, the components work with each other.
One component is radio frequency management, which is based on hard data about such things as signal strength, noise, errors and interference throughout your entire net, says Snyder. Some vendors can dedicate one radio on a multiradio access point to this monitoring; others have dedicated "sensors"; still others switch their regular access point from traffic to monitoring modes and back. Does the software handle alerts and reports on this data, and how well does it handle them?
Related to this data is WLAN capacity management, says Snyder: Does the management system give you an accurate, consistent, up-to-date view of the level of WLAN activity in each area, and how this changes during the course of a day or week? Tools for capacity planning show you where you need to make changes in the number of access points or in coverage to optimize performance for wireless services.
How does the vendor support wireless security management? This category is a grab bag of features, says Snyder, varying widely from vendor to vendor. It can include intrusion detection/prevention features, as well as firewalls, features analogous to wired network access control and WLAN access for guests or visitors.
When evaluating device-configuration management, Snyder suggests, consider the entire life cycle of the net devices: What does it take to add access points or radios, to keep them up and running, and to retire or replace them as needed.
Snyder terms mobility management as the fifth component of managing a WLAN – how a user and his session, permissions and authentications can move through the net. With the advent of wireless VoIP, and an emerging trend to hand off VoIP calls between WLANs and cellular nets, you may need new, expanded or more robust mobility features from vendors.