November 2010 E-newsletter
Wireless Management Matures
Wireless local area networks (WLANs) have come a long way since the 1990s when the technology was expensive and standards were new.
Much of wireless networking's success can be attributed to the fact that it's more stable, fast and cost-effective today, thanks to mature standards-based equipment. But just as important, network managers now have sophisticated, yet easy-to-use management and monitoring tools at their disposal – and these tools are becoming even better at troubleshooting, measuring performance and boosting quality and service levels.
“For a period of time, wireless network management for manufacturers was a must-have sideshow,” says Jim Frey, research director with Enterprise Management Associates.
“A lot of the technology needed to mature, and now it has,” he says. “Wireless access points are supported by most of the management tools and brought under the same scrutiny and control as any other network node.”
The tools, available from all the major providers of wireless networking equipment, including Aruba Networks, Cisco Systems and Meru Networks, now have features that let network managers configure, test and monitor performance of access points, as well as enforce policies and compliance across the WLAN. Air quality measurement, known as spectrum analysis, is now becoming an integral part of a WLAN, as opposed to a separate, manual tool.
Brent Engelhardt, network specialist at Round Rock Independent School District in central Texas, uses core network management and monitoring tools from Aruba Networks to manage the district's wireless network. The network, which has been built out over the past two years, runs over 10 controllers and about 1,700 access points, all from Aruba Networks. By the end of the project, Engelhardt estimates there will be about 1,800 access points. Right now, at peak times there are about 3,000 users on the network districtwide; 100 of those are guest clients.
The management tools help Engelhardt better understand the status of the district's access points, determine where network congestion occurs, manage the controllers, and monitor aspects of the end-user devices (such as signal strength, the length of time on the network and which access point is connecting the end-user device).
Engelhardt also uses Aruba's AirWave to monitor how devices are authenticated for access to the network and whether those devices are authorized. He says the AirWave RAPIDS module helps detect rogue access points.
The module uses existing, authorized access points to scan the radio frequency environment for any unauthorized devices in range, and captures and manages intrusion detection identified by WLAN controllers. It also correlates all of this data and uses a set of customizable rules to highlight the devices that threaten the network, its performance and integrity.
Engelhardt also leverages the Visual RF feature, which lets him create a two-dimensional map in AirWave and then define the coverage areas. “It can assist in finding coverage holes in the building and locations of clients. And it also can help show where any rogue access points are,” Engelhardt says.
Another district that uses the latest tools to manage its wireless network is Farmington Municipal Schools, in the northwest corner of New Mexico. The staff and sixth- through 12th-graders in the district use about 5,000 notebooks deployed over a wireless network that includes 134 access points and three controllers from Meru Networks.
The range that 802.11n wireless devices can cover in a home, office or outdoors
Source: Wi-Fi Alliance
Charles Thacker, chief technology officer for the district, says managing the wireless network is vital.
“We are in a society where access to anything, anytime, from anywhere is expected. We are encouraging that expectation with the notebooks and with our wireless,” says Thacker.
“Our IT staff needs to make sure it's reliable and usable,” he adds. “Without centralized management and a strong wireless network, we will have staff and students giving up on the use of technology as a tool because they can't rely on it.”
Thacker and his team use the basic suite of tools built into the Meru controllers, which lets them monitor traffic, client loads and the status of access points, as well as track the general location of equipment on the campus. The management tools that network managers now have to monitor the wireless networks have become so sophisticated that specialists such as Thacker don't have time to use all the capabilities.
“I personally would like to have more time to get in and tweak a few things here and there to provide even more features to our wireless LAN, but the real strength in the Meru concept is that while the knobs and dials for twiddling and fine-tuning are there to use, it's often not necessary to spend time doing that since the network simply runs and works once it's set,” Thacker says. “It's close to the nirvana that we like in our district, where it just works and you set it and forget it.”
Look for Integrated Spectrum Analysis
Radio frequency interference in a WLAN is a fact of life. That's because WLANs operate in the unlicensed bands of the radio spectrum, and regulations require that these bands accept any interference. Most interference isn't nefarious, but it can wreak havoc on your WLAN's performance. It can reduce data throughput and range, hurt the quality of voice and video applications and can sometimes even bring down a link.
To uncover and remedy RF interference, most network engineers rely on stand-alone spectrum analyzers that have to be carried out into the field to check for problems. But increasingly, manufacturers are integrating spectrum analysis into the access points themselves. Aruba offers this via its spectrum analysis module; Cisco Systems recently announced its CleanAir product line of new access points that integrate spectrum analysis functionality; and Meru Networks offers it via its Meru Air Traffic Control and Spectrum Manager.