Wireless LAN Security Concerns

From a security point of view, wireless LANs represent a new method for accessing
the enterprise network. In much the same way that enterprise network managers
have previously faced the challenges of securing local LAN access, remote LAN
access from the Internet, and remote LAN access from cellular networks, network
managers must consider the new challenges introduced by LAN access from an in-
building wireless LAN.
Wireless LAN deployments raise a number of security concerns. Possible security
threats include unauthorized use of the network, eavesdropping on transmitted data
traffic, and denial of service attacks.
While these threats are present in traditional LANs, the wireless environment
exacerbates these concerns significantly:
1. Broad network exposure. Wireless LAN range and signal propagation are
largely uncontrollable, so potential intruders on the LAN need not be
physically located within an enterprise’s premises; 802.11b networks easily
reach out into the parking lot and may even provide wireless coverage to
i
people driving along nearby streets.
This concern is particularly relevant in
shared office buildings.
2. Invisible intruders. Even within an enterprise, wireless LAN intruders can
operate inconspicuously because they do not need a physical connection to
the network. With the emergence of handheld devices capable of
communicating over 802.11b networks, the inability to monitor user actions is
of even greater concern.
3. Guest access. Guests and visitors increasingly expect enterprises to offer
Internet access, in the same way that they ask to borrow the telephone or fax
machine today. Many guests have wireless LAN-enabled laptops and
handheld devices, and they seek to access the Internet using this equipment.
Unfortunately, offering this access typically involves granting non-employees
use of the corporate LAN.
4. Rapid technology evolution. Wireless LAN technologies are relatively
new. The security mechanisms provided by these standards are untested,
and the standards are evolving rapidly. Moreover, in the near future,
enterprises will likely face heterogeneous wireless LANs encompassing
multiple radio standards, including 802.11b, 802.11a, 802.11g, HiperLAN2,
Bluetooth, and 802.15. Managing security in such rapidly evolving,
heterogeneous wireless LAN environments represents a considerable
burden.
These security issues represent a significant challenge to IT managers who are
considering the deployment of in-building wireless networks within the enterprise.