Advances
in securing wireless networks
Dec 6, 2000
Dawn Marie Yankeelov
Wireless network security is becoming an issue of national importance,
as evidenced by the U.S. Federal Trade Commission's announcement in
November to hold a December workshop to analyze security and other issues
surrounding wireless Internet access.
Security concerns have already become a key issue for wired networks. In
the annual Computer Security Institute/FBI Computer Crime and Security
Survey this year, most U.S. corporations reported attacks on networks in
the past 12 months. Less than half knew the actual dollar value, but 273
companies reported cumulative losses of $265.6 million.
Wireless LANs (WLANs) encounter many of the same security problems that
affect a wired LAN, plus a few more. In a wireless environment, the
potential for a transitive trust attack and infrastructure denial of
service attacks appears to be higher.
Mike Vergara, director of product marketing at RSA Security, Inc., the
largest security company in the United States by revenue, said that
authentication is the key to WLAN security.
"In my opinion, the most important element to encourage is
authentication. People are just not doing it with consistency in wireless
networks," Vergara said. "I'm not speaking of confirming that a particular
computer is on the wireless LAN. I'm talking about confirming who is on
the computer on the LAN."
The Federal Trade Commission, like many users, is looking to hear a
"state-of-the-union" message on wireless networks and technologies. High
on the list will be the issue of personal data security and the chances of
widespread identity theft as more wireless devices converge into single
products. WLANs operate in the same portion of the 2.4-GHz band, creating
a need for caution.
"Most users are lazy, and they are the weakest link in the security
chain for wireless networks," Vergara said. "People worry about data
privacy-someone stealing their credit card number in transit-but the
technology exists to solve that problem now. It just has to be used."
Existing security measures
The basic Institute of Electrical and Electronics Engineers 802.11
wireless standard provides for two methods of security: authentication and
encryption, both of which are receiving industry-wide attention.
Authentication refers to the way in which one station is verified to
have authorization to communicate with a second station in a given
coverage area. Generally, in the infrastructure mode, authentication is
based between an access point and each station with either an open system
or a shared key. In an open system, any station may request authentication
and the station receiving the request grants authentication based on a
user-defined list. In a shared key environment, optional encryption plays
a hand.
Encryption in a WLAN allows for a level of security comparable to that
of a wired LAN. In the IEEE 802.11 standard, the Wired Equivalent Privacy
(WEP) feature uses the RC4 Pseudo-Random Number Generator (PRNG) algorithm
from RSA Security, Inc. The IEEE accepted this algorithm because it is
self-synchronizing, computationally efficient, exportable, robust, and
optional.
In October, RSA Security announced its support of the new Advanced
Encryption Standard (AES) and previewed plans to incorporate this
symmetric key algorithm into its security software. The National Institute
of Standards and Technology (NIST) announced that the Rinjdael algorithm
was chosen to become the new AES. This replaced the current Data
Encryption Standard (DES) algorithm.
The minimum encryption built into 802.11b WLANs should be sufficient for
many applications. A user can implement network layer encryption, such as
Internet Protocol Security (IPSec) across both wired and wireless portions
of the network, eliminating the need for 802.11 security. The customer can
have critical applications encrypt their own data, including network data
such as Internet Protocol (IP) and Media Access Control (MAC) addresses.
Potential gaps
The primary culprit in compromised security is human error in not
turning on security features, according to security analysts involved in
the wireless field. The built-in WEP encryption protocol must be turned on
after installation. Gartner analyst John Pescatore, who formerly worked in
national security, estimated earlier this year for Computerworld that only
about 20 percent of users actually turn on the WEP feature. (TechRepublic
is a subsidiary of Gartner.)
Other access control methods are possible, such as the identification
value called an Extended Service Set ID (ESSID), which is programmed into
each access point to identify which subnet is on. This can be used to
check authentication.
In November, the Datamonitor group issued a white paper based on
research that focused on 25 major companies worldwide. The paper tabulated
research from more than 12,000 consumers, and the results suggested that
more than $15 billion worth of damage worldwide is caused by e-security
breaches. Yet business investment on network security is only half that
figure. Datamonitor reported that more than 50 percent of businesses
worldwide spend just 5 percent or less of their IT budget on securing
their networks. Education and user knowledge of what steps can be taken
were cited as paramount in the report.
New tools for users
A number of companies at Comdex 2000 announced devices and products that
assist in securing wireless devices and networks. Among the new offerings
was Ensure Technologies' XyLoc 3G, the third-generation of its wireless PC
security solution. Xyloc 3G automatically secures notebooks and personal
computers when the user steps away and unlocks the PC upon the user's
return, sometimes requiring additional authentication. New features
include XyCrypt, which automatically encrypts files to prevent
unauthorized access, and the Personalization Wizard, which allows custom
settings. Ensure also added the advanced wireless protocols of Bluetooth
to this release.
VeriSign has seen a market opportunity to offer a wireless developer
program that will eventually help make buying items from the Web using a
mobile device as secure as doing so from a desktop. It also has plans to
collaborate with the WAP Forum to beef up the security of the wireless
protocol. VeriSign approaches security issues by creating a certificate
infrastructure on the server and client side. Motorola, in agreements with
VeriSign, Entrust Technologies, and Baltimore Technologies, embeds
certificate and PKI code in its WAP gateways already.
VeriSign, which is a spinoff of RSA Security, could see additional
business from users of wireless networks, since the digital certificate
provides a form of authentication. "It could serve a purpose for VPNs and
wireless VPNs," Vergara said.
New tools for wireless networks
At the server level, Lucent Technologies has released its new ORiNOCO
AS-2000 access server for WLANS, featuring per-user, per-session
encryption that provides high levels of security to each wireless session.
It also adds a built-in RADIUS Client that enables user authentication,
authorization, and accounting to control access to the entire wireless
network. This is a leap from the traditional shared-key wireless LAN
systems, eliminating the need for manual intervention.
And earlier this year, Cisco presented a proof-of-concept demonstration
of its next-generation security capabilities for WLANs, involving the next
IEEE draft proposal 802.1x and the Extensible Authentication Protocol (EAP).
The system provides robust security administration and management in
Windows 2000 clients for user-based authentication and wireless security
management.
Have you had problems with wireless security?
Have you trained your users on how to work securely? Has your wireless
network ever been invaded? Send us your tips on how to keep your wireless
network secure.
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