* Cognitive radio technology
Cognitive radio enhances WLANs
By Nestor Fesas and Bob Mayer
The explosive growth of wireless technologies has created managerial challenges for those who oversee wireless networks. With wireless intrusion threatening security and radio frequency interference impeding performance, IT managers need an up-to-date, detailed understanding of the RF environment to make informed decisions about how to solve these problems.
Cognitive radio technology enables a radio device and its antenna to sense its RF environment and adapt its spectrum use as needed to avoid interference. Integrated software and silicon solutions enable cognitive radio to be built into enterprise-class wireless LAN (WLAN ) access points to boost security and optimize performance. Access points with this feature are expected to be available next year.
Wireless intrusion occurs when unauthorized WLAN users gain access to a secured network. Causes include hackers creating ad hoc networks with WLAN clients or a rogue access point connected to a wired network without proper security levels. In either case, the keys to prevention are quick identification, containment and defensive action.
The first step in preventing wireless intrusion is identifying the intrusion point. Because WLANs are fixed to a specific WLAN channel during operation, they cannot simultaneously detect intrusion points on other WLAN channels. Relying on a single-radio access point to provide access and security is insufficient. Network managers must be able to monitor the full WLAN frequency range to be able to reliably detect and identify intrusion points.
Cognitive radio for WLANs provides a means to observe the RF environment in the 2.4-GHz and 5-GHz frequency bands within which IEEE 802.11 WLANs operate without disrupting normal wireless VoIP and data traffic. Continuous scanning of both bands for 802.11 and non-802.11 devices allows for timely detection of intruders.
To read more about cognitive radio technology, please go to: http://www.networkworld.com/news/tech/2005/111405techupdate.html?rl
