07-10-2010, 04:15 PM
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Wireless LAN Security 802.11b and Corporate Networks
Introduction
Although a variety of wireless network technologies have or will soon reach the general business
market, wireless LANs based on the 802.11 standard are the most likely candidate to become
widely prevalent in corporate environments. Current 802.11b products operate at 2.4GHz, and
deliver up to 11Mbps of bandwidth – comparable to a standard Ethernet wired LAN in
performance. An upcoming version called 802.11a moves to a higher frequency range, and
promises significantly faster speeds. It is expected to have security concerns similar to 802.11b.
This low cost, combined with strong performance and ease of deployment, mean that many
departments and individuals already use 802.11b, at home or at work – even if IT staff and
security management administrators do not yet recognize wireless LANs as an approved
technology. This paper addresses the security concerns raised by both current and upcoming
802.11 network technologies.
Wireless LAN Business Drivers
Without doubt, wireless LANs have a high gee-whiz factor. They provide always-on network
connectivity, but don’t require a network cable. Office workers can roam from meeting to meeting
throughout a building, constantly connected to the same network resources enjoyed by wired,
desk-bound coworkers. Home or remote workers can set up networks without worrying about how
to run wires through houses that never were designed to support network infrastructure.
Wireless LANS may actually prove less expensive to support than traditional networks for
employees that need to connect to corporate resources in multiple office locations. Large hotel
chains, airlines, convention centers, Internet cafes, etc., see wireless LANs as an additional
revenue opportunity for providing Internet connectivity to their customers. Wireless is a more
affordable and logistically acceptable alternative to wired LANs for these organizations. For
example, an airline can provide for-fee wireless network access for travelers in frequent flyer
lounges – or anywhere else in the airport.
Market maturity and technology advances will lower the cost and accelerate widespread adoption
of wireless LANs. End-user spending, the primary cost metric, will drop from about $250 in 2001
to around $180 in 2004 (Gartner Group). By 2005, 50 percent of Fortune 1000 companies will
have extensively deployed wireless LAN technology based on evolved 802.11 standards (0.7
probability). By 2010, the majority of Fortune 2000 companies will have deployed wireless LANs
to support standard, wired network technology LANs (0.6 probability).
Reality Check
For the foreseeable future wireless technology will complement wired connectivity in enterprise
environments. Even new buildings will continue to incorporate wired LANs. The primary reason is
that wired networking remains less expensive than wireless. In addition, wired networks offer
greater bandwidth, allowing for future applications beyond the capabilities of today’s wireless
systems.
Although it may cost 10 times more to retrofit a building for wired networking (initial construction
being by far the preferred time to set up network infrastructure), wiring is only a very small fraction
of the cost of the overall capital outlay for an enterprise network. For that reason, many
corporations are only just testing wireless technology. This limited acceptance at the corporate
level means few access points with a limited number of users in real world production
environments, or evaluation test beds sequestered in a lab. In response, business units and
individuals will deploy wireless access points on their own. These unauthorized networks almost
certainly lack adequate attention to information security, and present a serious concern for
protecting online business assets.
Finally, the 802.11b standard shares unlicensed frequencies with other devices, including
Bluetooth wireless personal area networks (PANs), cordless phones, and baby monitors. These
technologies can, and do, interfere with each other. 802.11b also fails to delineate roaming(moving from one cell to another), leaving each vendor to implement a different solution. Future
proposals in 802.11 promise to address these shortcomings, but no shipping products are on the
immediate horizon