Managing Over the Airwaves

As wireless LANs grow, companies are seeking ways to monitor and manage traffic and devices. The challenge is picking the right software for the job.

Setting up a wireless LAN opens up a whole new set of network management challenges: balancing traffic loads, running reports, handling remote firmware upgrades, resolving channel conflicts, architecting for maximum throughput, supporting products from multiple vendors, integrating existing management software with the new system, and supporting a variety of devices.

When ABC Fine Wines & Spirits in Orlando rolled out an 802.11b network to 152 stores this spring, remote software deployment was the key. "Initially, the problem was getting the applications down to the devices in the stores," says help desk manager Guy Ledbetter. "Then we have to manage the software and firmware that is on those devices, as well as the network connectivity."

Fortunately, as the popularity of such networks has grown, so have the options available to monitor and manage them. The trick is finding the right tool out of the dozens on the market. In ABC's case, it was Kirkland, Wash.-based Wavelink Corp.'s Avalanche product, which let ABC download the software to several hundred wireless devices in its stores and perform upgrades later.

"WLAN management is one of the hottest areas of technology right now because these networks are reaching the size, scope and complexity where their management limitations become very evident," says Warren Wilson, an analyst at Summit Strategies Inc. in Boston. "This puts a premium on simplifying deployment and operations and providing greater visibility into the network."

The WLAN management market can be broken into two major segments. Some tools come from the hardware vendors themselves. For example, management functions are built into the switches from Airespace Inc. and Aruba Wireless Networks Inc., both in San Jose, and Trapeze Networks Inc. in Pleasanton, Calif. And Cisco Systems Inc. just announced its Structure Wireless-Aware Network, a mix of hardware and software that will be available later this quarter that's designed as a complete package for deploying enterprise-class WLANs.

But other products address specific areas of management pain, particularly those related to encryption, authentication, signal strength and traffic management. The key is to match the capabilities of the software to the challenges you are trying to deal with.

For DiamondCluster International Inc. in Chicago, the problem was finding a single way to implement security on all its WLANs. The company arose out of the merger of North American management consulting firm Diamond Technology Partners with Cluster Consulting, which had offices in Europe and Latin America. Each of DiamondCluster's nine offices has its own 802.11b WLAN, with one to eight access points at each location. But these WLANs grew up independently, with different authentication methods, depending on the hardware each location used. This significantly limited their usefulness.

"We were looking for a standardized way to secure the wireless network," says Drew Jemilo, IT director of Internet technologies at DiamondCluster. "We needed to make it so that users could go to any network around the globe, turn on their laptops and connect."

Jemilo wanted to do this without replacing hardware. So he looked for a software-only system that could run on existing file and print servers at smaller offices while scaling up to the needs of larger ones.

DiamondCluster piloted Seattle-based NetMotion Wireless Inc.'s Mobility WLAN security and management product. The client software checks for the best available connection, whether wired or wireless, and initiates the connection with the Mobility server, which handles authentication and encryption.

After finalizing the architecture and configuration options, DiamondCluster rolled Mobility out to all of its offices, a process that took about six to eight hours per location.

"There is a lot of flexibility to using a tool that is platform-independent," says Jemilo. "It worked with all the wireless cards and all the access points we already had in place."

Who Needs Them?

Administrators have dozens of WLAN tools to choose from. But which do they really need?

"The ability to detect rogue access points is essential," says Ken Dulaney, an analyst at Gartner Inc. in Stamford, Conn. "Everything else is 'nice to have.'"

Wilson agrees that companies with installations under a certain size can still manage their networks manually. But he says even small WLANs may need additional tools in the following three cases:

1. Dense usage areas: If you have WLAN access in a conference room and 20 people are trying to download a speaker's PowerPoint presentation, that poses a different set of management challenges than an area with more distributed access.

2. Radio frequency interference: Certain areas have unusually high RF interference, particularly in a manufacturing or health care environment. "Factory machines can emit constant or bursts of RF energy that can disrupt WLAN traffic and even be so strong as to knock out the settings on an access point," says Wilson.

3. Poor quality of service: If you're just sending e-mail or application data, quality of service isn't a major concern. But other types of WLAN traffic, including video and voice traffic, require better service.

Of course, when you get down into the specifics of one particular network, the broad rules don't necessarily apply. Situations when site-survey tools are used are one such example.

"The site-survey tools are typically only used in the initial deployment stage," says Aaron Vance, an analyst at Synergy Research Group Inc. in Phoenix. "They get the ball rolling but are only used once."

But for the Cherokee Nation, site surveys are an ongoing process. The tribe has a 1.5Mbit/sec. frame-relay WAN connecting offices and medical facilities spread throughout 10,000 square miles in northeastern Oklahoma, as well as Gigabit Ethernet backbones in most of its buildings. But a dozen locations use Wi-Fi. "Some of the remote nodes don't have enough users to pull fiber to the buildings," says IT manager Jon James. "Also, some are in rented facilities, so we can't put wires in the walls."

James needed an easy way to conduct wireless surveys at those remote sites. Although he can put the Cisco access points he uses into survey mode, he says that doing so would still require the technicians to haul too much equipment around with them. Instead, he bought Sunnyvale, Calif.-based AirMagnet Inc.'s AirMagnet Combo, a wireless analysis tool that works on either a laptop or a Pocket PC device.

"It is a lot easier to carry around the PDA than to lug around a laptop and all its accessories," says James.

DiamondCluster's Jemilo finds a survey tool indispensable, since his company rents office space and its operations frequently move to new locations. Even shifting furniture within an office can cause problems, he says. For example, a new file cabinet could block the signal to a desktop that formerly had adequate reception.

For Stanford Law School in Palo Alto, Calif., the problem wasn't conducting security or site surveys, but determining an easy way to manage what it had in place.

"I was getting no metrics, no reporting, and had no way of managing wireless nodes," says Mike Noe, describing the scene when he started as director of IT last year. "When a professor requested that an access point be turned off during an exam, one of my guys had to climb up on a stepladder and unplug it."

Earlier this year, Noe loaded the AirWave Management Platform from AirWave Wireless Inc. in San Mateo, Calif., on a small dedicated server, and the software automatically detected all access points. The entire setup process took a couple of hours.

After installing and configuring the software, Noe could use its reporting features to locate peak usage periods and network choke points. While these monitoring functions are useful, Noe's favorite feature is the ability to remotely manage the access points.

"Some of the instructors want wireless in their classrooms, and some don't," he says. "Now we can turn the access points on or off in a few seconds."

Fixing Deficiencies

As these cases show, no single type of tool will meet the needs of all administrators. Each user faced a unique set of issues, and a piece of software existed to address those issues. Those tools aren't interchangeable. They each bridge different gaps left by the hardware manufacturers and other WLAN management tools and systems.

"Much of the market for wireless management tools has been built on the deficiencies of the WLAN manufacturers' offerings," says Christopher Noble, a London-based network and infrastructure analyst at The451. "Until recently, with the advent of larger corporate deployments, the main manufacturers have been lacking in their ability to monitor and manage the RF portion of wireless LANs."

But as the market matures, Noble and other observers expect to see more of these features built into the access points and switches.

Robb is a freelance writer in Los Angeles. You can reach him at

See more news, analysis, advice and opinions on this issue in our Mobile/Wireless Knowledge Center.

Copyright © 2003 IDG Communications, Inc.

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