WLAN Switches Take Off Weight

In the Wireless LAN (WLAN) market, thin is in. Faced with declining unit growth and falling product prices in the consumer market, vendors have focused on boosting their sales to enterprises. While this strategy has merit, it has meant that they have had to redesign their wares.

Consumers are content with “fat” access points, devices that function as self-contained units, supporting transmission, security, and management functions. Enterprises desire “thin” units, products that handle transmission functions locally but depend on central security and management systems. “Just about all of the WLAN vendors have been trying to add thin access points to their product lines,” noted Abner Germanow, program manager at market research firm International Data Corp.

WLANs have been an area filled with product design compromises for suppliers. Wireless transmissions are complicated and much more susceptible to delays and outside interference than wired connections are. In building the first versions of their access points, suppliers focused on making sure they delivered sufficient bandwidth to support user applications. With the advent of new standards and improved microprocessor design, that is no longer a significant challenge so suppliers have moved on to other features.

Security and management have been two weak areas for WLANs. “The first WLAN standards had pronounced security holes, and the access points were difficult to manage,” stated Rachna Ahlawat, a research director at Gartner Group. Attempts to solve these problems have led to the introduction of thin access points, which possess strengths and weaknesses.

WLAN Security Holes Exposed

Security has been a major concern for enterprises. Initially WLAN systems encrypted data as it traveled between users and access points, but they lacked strong authentication mechanisms, intrusion detection functions, and rogue access point control. As a result, they were favorites for hackers. Wardriving, for instance, is a technique where hackers drive or walk up and down streets, identify WLANs, and try to illegally tap into them.

Employees may also purchase access points from local retailers and connect them to corporate networks without setting acceptable security controls, so there are openings that mischievous individuals can exploit. Once inside the network, an intruder is able to change security parameters and reset privileges, so all of the network resources are at his disposal.

The thin-client approach provides corporations with more control over their WLANs. A wireless switch relies on a company’s security policies to authenticate and configure each access point dynamically. If an employee or hacker tries to plug into the network, the wireless switch disables the connection if an access point is unable to authenticate itself. Additionally, a wireless switch prevents authorized users from tinkering with security policies, so hackers cannot change network settings.

Improved coverage is another potential thin-client benefit. Because there are so many variables in network configuration (interference from cubicles, walls, and office equipment; device battery life; the variety of data transmitted), setting up a WLAN that provides adequate bandwidth is challenging. Initially a network may operate effectively but when a change occurs, performance plummets. This task is exacerbated because usage patterns often change as users become comfortable with the technology. A switch may operate fine for days, months, or even years, and then a department will add an application, such as Voice over IP, and network performance suffers.

With fat access points, the IT department has to collect information from all the network connections, examine them, pinpoint the problem spot, and then make the necessary change. In a thin network, the wireless switch automatically collects that data and in a growing number of cases can dynamically change network configurations, so such problems are minimized.

Difficult Transition Points

Another shortcoming is WLAN connections may be dropped as users walk from areas with strong signals to one with weak ones. Most traditional fat access points have difficulty handing off transmissions because there is no central clearinghouse monitoring connections. This limitation can be problematic with applications, such as VoIP, which require stable bandwidth as users move about. Because of their centralized architecture, thin access points can complete handoffs more effectively and avoid the problems that come when connections stall or are dropped.

Because they have an autonomous design, fat access points are difficult to maintain. IT technicians need to complete chores, such as upgrading access point software or resetting security parameters, individually rather than collectivity. “Companies are moving from the phase where they had a few hundred WLANs to a period where they have thousands of them,” Gartner Group’s Ahlawat told TechNewsWorld. In such cases, WLAN maintenance costs can be higher than the initial cost of hardware and software.

Yet there are some downsides with thin access points. The price for a thin access point tends to be less than a fat one, but the overall network cost usually is more. “In a thin access point environment, a user has to put in a switch, which is often quite expensive,” said Greg Collins, senior director of mobility research at Dell’Oro Group.

Out-of-the-Box Functionality Missing

Fat access points are simpler to deploy than thin ones. Since the former come with all of the intelligence needed in an end point, users can take them out of their boxes, turn on the power, and have them running in a short period of time. Thin access points have a master/slave design, so more thought has to be put into their configuration.

The new systems do not work with the older ones. “Some enterprises have already made a significant investment in fat access points and will not be willing to change,” noted Dell’Oro Group’s Collins.

Compatibility among different vendors’ thin access points can also be a problem. Vendors are trying to differentiate their offerings through some of the different central management functions that they offer. While such work provides companies with needed functionality, it also means that companies cannot mix and match these devices because the features on one system may not be compatible with the features on another system.

Despite those issues, interest in thin systems has been on the rise. Vendors started shipping thin access points in bulk in 2004, the market received a dramatic validation in January when Cisco paid US$450 million for Airespace, a start up company that had been focused on building these systems. “Now that vendors can offer companies access points that are easy to deploy and manage, I expect revenue from the enterprise WLAN market to be greater than sales in the consumer market,” concluded Gartner Group’s Ahlawat.

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