If you have a wireless NIC and have spent much time in a facility equipped with an 802.11b infrastructure, you've probably experienced the benefits of wireless for yourself. Using a wireless infrastructure frees you from an Ethernet tether to the nearest network wall plate. Wireless technology facilitates project collaboration between team members—you can take your laptop with you to meeting rooms and coworkers' offices and stay connected to the network. And wireless obviates the need to pull new cable runs for every new office. Given these advantages, we'll no doubt see increasing rates of adoption for wireless technology in the near future.
Wireless Privacy: An Oxymoron?
Although the benefits of wireless are great, is now the best time to jump onto the wireless bandwagon? The current generation of 802.11b wireless technology isn't without limitations. First and foremost, the standard has serious security vulnerabilities. The related Wireless Equivalent Privacy (WEP) standard notwithstanding, 802.11b is essentially insecure. WEP specifies the use of the 40-bit RC4 encryption algorithm to scramble all 802.11b data before transmission. However, the WEP standard doesn't specify some of the most crucial parts of the algorithm, such as the frequency of key generation, and leaves implementation up to hardware vendors. Some vendors use proprietary 128-bit extensions, but these extensions typically don't interoperate with other vendors' equipment. Even when vendors implement frequent key regeneration in their products (and not all of them do), products are still open to a variety of well-known passive and active attacks, and several freeware tools assist would-be intruders in breaking into wireless networks. You can find more information about WEP security vulnerabilities in the articles listed in "Related Articles in Previous Issues" and at http://www.isaac.cs.berkeley.edu/isaac/wep-faq.html.
Worse, many IT administrators and home users don't even bother with WEP and set up essentially unsecured wireless implementations (a problem of behavior rather than technology). Various Web sites even post city maps that show unsecured wireless networks—maps that intruders have assembled by war driving (i.e., driving around and scanning for open wireless signals).
Probably the best solution to wireless technology's security problems is running a VPN on your wireless network, but doing so adds setup complexity and slows performance. Even without a VPN, 802.11b performance can be a concern. The standard rate for wired connections is now 100Mbps, and moving back to 802.11b's 11Mbps speed is hard—even harder when you discover that under shared conditions or in suboptimal surroundings, the speed can drop to 2Mbps or slower.
802.11 Alphabet Soup
Perhaps even more troubling than wireless technology's current security problems and low speeds is the wave of new wireless standards about to break over the marketplace. Although 802.11b is the current de facto standard, vendors recently released competing 802.11a products. Also, no fewer than three other new wireless standards are due to be released in early 2003: 802.11e, 802.11f, and 802.11g. Another 802.11 standard—802.11i—is scheduled for ratification in late 2003 or early 2004.
To sum up the differences between standards in this wireless alphabet soup: The current 802.11b operates in the 2.4GHz range at speeds of up to 11Mbps for distances of up to 300'. The new 802.11a operates in the 5GHz range at speeds of up to 54Mbps for distances of up to 60' and is incompatible with 802.11b. 802.11e adds to the 802.11a and 802.11b standards a Quality of Service (QoS) layer for better performance for selected applications. 802.11f adds multivendor interoperability to 802.11 products. 802.11g has 54Mbps speed and compatibility with the 802.11b standard; 802.11i is aimed at improving wireless security, including authentication.
As with any emerging technology, if your company foresees a payback in implementing the current generation of wireless products, you're justified in moving forward. However, the wireless times are clearly a-changin'. If you haven't jumped on the wireless bandwagon, you might want to hold off until the second half of 2003—after the dust from the next generation of wireless standards has settled.
| Related Articles in Previous Issues |
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You can obtain the following articles from Windows & .NET Magazine's Web site at http://www.winnetmag.com. SHON HARRIS "802.11 Security Shortcomings," December 2001, InstantDoc ID 22934 ALLEN JONES "Securing 802.11 Wireless Networks," June 2002, InstantDoc ID 24873 MARK WEITZ Market Watch, "802.11 Wireless LANs," January 2002 Web Exclusive, InstantDoc ID 23322 |
