Oct 11 2007

802.11n: Completing a Bigger Pattern

Agencies plan for ways to use upcoming wireless standard to extend connections.

The emerging 802.11n wireless protocol is slated to deliver as much as five times the throughput and twice the range of previous versions of the standard. Given its increased interference, interoperability and security challenges, however, the technology is eyed in government circles most notably as a way to supplement other forms of connectivity, rather than provide a standalone network.

“I see 802.11 technologies in the same circle as satellite or cellular technology — feeding the wired network,” says Jim Russo, telecommunication program manager with the Federal Acquisition Service at the General Services Administration. “They really sort of complete a bigger pattern.”

Ongoing Security Concerns

Perhaps the greatest barrier to accelerating deployment of wireless local area networks in the government is unease about security and where the new 802.11n specs will fall on the security spectrum, says Russo.

Mature technologies are in place to ensure that wireless networks are not intercepted, but there remains a reluctance to deploy wireless LANs while users and administrators are still trying to familiarize themselves with the latest security measures, he says. That makes the move to the latest products, built around the draft versions of 802.11n, a quandary.

Plus, notes Russo, there’s the training issue. With a user base the size of the government, the cost of training and logistics can dwarf the technological challenges of a new standard, he says.

“There’s still a lot of knowledge that has to be absorbed across all the agencies,” Russo says. “The technology is only a small part of that equation. Any time you roll out a new technology, the price of the equipment is almost microscopic compared to training the people using it and putting the support logistics in place.”

At the Defense Department, which has been actively deploying wireless LANs, a wireless intrusion detection system (WIDS) is a required component of any wireless security infrastructure, but its limited support for 802.11n raises challenges for deploying the emerging standard, says Danny Price, deputy director of the Communications Directorate in the Office of the Assistant Secretary of Defense for Networks and Information Integration. Given the anticipated enhancements in range and wall penetration, 802.11n might not be suited to the WIDS designed for 802.11 a, b and g, he says.

Security concerns aside, the greatest 802.11n challenge for Defense is the delayed ratification of the standard, Price says. Once the Institute of Electrical and Electronics Engineers ratifies the standard, which is expected late next year, agencies will have to wait for the Wi-Fi Alliance to approve products. Then they will have to wait for the National Institute of Standards and Technology to test and validate the products’ cryptographic modules.

Despite the nuisance of delays, DOD will wait, because adopting standards is always preferable to proprietary adaptations, Price says.

“It is not necessary for DOD to adapt 802.11g technologies, in a proprietary way, in order to achieve the benefits of 802.11n,” he says. “DOD embraces open standards, as they are introduced into the industry in order to provide for interoperability across a large enterprise.”

General Thinking

When contemplating the deployment of any wireless LAN, a consideration for any agency is the kind of radio frequency (RF) environment in which the technology will be used, Russo says. Challenges and capabilities vary considerably, depending on whether the network is implemented in a typical office building or a more open space, such as in an emergency response situation.

One of the most suitable environments would likely be a temporary facility used by a single team, where signals are less likely to confront the level of competing signals and RF impediments often found in office buildings. In such situations, 802.11 technologies offer good potential for extending other network connections, such as satellite, Russo says.

At DOD, where operations often take place in relatively controlled RF environments, 802.11 technologies are being used for a variety of logistics, training and network applications, Price says. The increased data rate of 802.11n could improve the efficiency of those operations, including perimeter video surveillance and multimedia networking.

Additionally, improved quality of service and increased range could motivate some users of earlier 802.11 technologies to upgrade once the latest standard is ratified, Price says. The Pentagon is looking at other emerging standards, including 802.16e, which is slated to offer higher data rates but with longer range, he adds.