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Security Risks and Ways to Decrease Vulnerabilities in a 802.11b Wireless Environment
By Richard Johnson
Introduction
This document explains topics relating to wireless networks. The main topics discussed
include, what type of vulnerabilities exist today in 802.11 networks and ways that you can
help prevent these vulnerabilities from being exploited. Wireless networks have not been
around for many years. Federal Express has been using a type of wireless networks, common
to the 802.11 networks used today, but the general public has recently just started to use
wireless networking technology. Because of weak security that exists in wireless networks,
companies such as Best Buy have decided to postpone the roll-out of wireless technology.
The United States Government has done likewise and is suspending the use of wireless until
a more universal, secure solution is available.
Background
What is Wireless?
Wireless LANs or Wi-Fi is a technology used to connect computers and devices together.
Wireless LANs give persons more mobility and flexibility by allowing workers to stay
connected to the Internet and to the network as they roam from one coverage area to
another. This increases efficiency by allowing data to be entered and accessed on site.
Besides being very simple to install, WLANs are easy to understand and use. With few
exceptions, everything to do with wired LANs applies to wireless LANs. They function like,
and are commonly connected to, wired Ethernet networks.
The Wireless Ethernet Compatibility Alliance [WECA] is the industry organization that
certifies 802.11 products that are deemed to meet a base standard of interoperability. The
first family of products to be certified by WECA is that based on the 802.11b standard.
This set of products is what we will be studying. Also more standards exist such as
802.11a and 802.11g.
The original 802.11 standard was published in 1999 and provides for data rates at up to
2 Mbps at 2.4 GHz, using either FHSS or DSSS. Since that time many task groups have been
formed to create supplements and enhancements to the original 802.11 standard.
The 802.11b TG created a supplement to the original 802.11 standard, called 802.11b,
which has become the industry standard for WLANs. It uses DSSS and provides data rates up
to 11 Mbps at 2.4 Ghz. 802.11b will eventually be replaced by standards which have better
QoS features, and better security.
Network Topology
There are two main topologies in wireless networks which can be configured:
Peer-to-peer (ad hoc mode) – This configuration is identical to its wired counterpart,
except without the wires. Two or more devices can talk to each other without an AP.
Client/Server (infrastructure networking) – This configuration is identical to its
wired counterpart, except without the wires. This is the most common wireless network used
today, and what most of the concepts in this paper apply to.
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