- The Wireless LANscape
- 802.11a/g: Linksys WRT55AG; 802.11b: ZyXEL ZyAir B-2000
- Belkin F5D7230-4
- Buffalo AirStation WBR-G54
- D-Link DI-624
- Linksys WRT55AG
- Netgear WG602
- SMC Barricade g 2804WBR
- Adaptec Ultra Wireless Access Point
- D-Link DI-614+
- Hawking H-WR258
- Linksys WAP11
- Microsoft MN-500
- Netgear ME102
- Siemens SpeedStream 2524
- U.S. Robotics 2249
- ZyXEL ZyAIR B-2000
- Cisco Aironet 1200 Series
- Proxim AP-2500
- 3Com AP8700
- WLAN Lingo
- Removing Security Roadblocks
- PC Magazine Recommends
- Performance Tests: Wireless LANs
- Management Solutions: A New Route for the Enterprise
- Maximum Range: The Case for Antennas
- Hands-On with WLAN Antennas
- Switch-Based Wireless Systems
- Cisco's Structured Wireless-Aware Network
- Summary of Features: Wireless LANs
Whether for business or home use, wireless LANs should be securedand at an absolute minimum that means turning on WEP, but soon there will be alternatives.
The convenience of an untethered network connection, coupled with the rapidly plummeting prices of wireless networking hardware, has led to an explosion in the number of wireless LAN (WLAN) installations over the past year. Unfortunately, most of them remain insecure.
Unlike traditional wired networks, wireless networks operate over the air using low-powered radios. With a range of up to 300 feet or more, depending on the antenna, the transmissions can be intercepted by anyone inside that radius with the proper equipment. And once intruders attach to an unsecured access point, they have access to your network and your Internet connection. They can potentially open or delete files or use your mail servers to launch a spam or denial-of-service attack.
In 1999 the IEEE tried to address these concerns by proposing an encryption-based security mechanism called WEP (Wired Equivalent Privacy). Since that time, though, WEP has proved fundamentally insecure. It encrypts every packet by combining a 24-bit Initialization Vector (IV) with either a 40-bit or a 104-bit WEP key, which is stored both in your access point and on your computer. The problem is that the IV is transmitted in plain text, and since it's only 24 bits long, there are only 224 possible combinations of encryption keys. An intruder armed with a publicly available tool such as AirSnort can eventually churn through these combinations and determine your WEP keyif he or she can capture and analyze enough packet traffic.
Since WEP keys are generally static, that data can be collected at the hacker's convenience over an extended period of time, taking anywhere from hours to days to crack depending on the volume of network traffic. Similarly, authentication mechanisms on most current wireless networks are weak. With open systems authentication, a client needs to know only the Service Set Identifier (SSID) of a network in order to connect. Most APs broadcast the SSID ten times per second, and Windows 2000 and XP display the SSIDs of the networks they hear.
With shared-key authentication, there's the additional requirement of needing the WEP key to associate with an access point. But as noted above, WEP keys can be hacked.
Finally, there's MAC (media-access control) address filtering. The access point grants access only to network cards whose MAC addresses have been permitted access. But MAC addresses are broadcast in the clear, and a hacker can easily "spoof" them.