User's Guide

life applications of the capability include: Geofencing, Prioritized Device Tracking, and Wi-Fi Device
Inventory.
Alarm Library
To view a list of Proximity Alarms for each alarm sub-type, go to Configuration > Operational
Management > Alarm Configuration, open Proximity, and then open the alarm sub-type to see all the
alarms associated with the sub-type.
Reconnaissance Alarms
Reconnaissance Alarms alert you to events that track devices which are actively attempting to locate
wireless networks. 802.11 wireless networking operates in a shared medium in which the wireless signals
are not constrained by the traditional physical boundaries. Signals may extend outside of building
boundaries into parking lots or neighboring faculties enabling valid client devices, attackers or malicious
users to receive the signals and discover available wireless networks. Wireless behavior from supplicants
such as such as Windows XP zero configuration client (WZC) is an example of normal reconnaissance
behavior where the client will continue to probe for all configured networks; this is normal
reconnaissance activity that allows the clients to find networks which do not broadcast SSIDs.
Alternatively, reconnaissance may be used by a malicious user as the first step in an attack on a wireless
network. Open source reconnaissance tools, such as Wellenreiter, Netstumbler, and Dstumbler, can be
used to discover wireless networks. Some reconnaissance tools use active methods to detect wireless
networks and are easily detected by ADSP, while other tools such as Kismet have transitioned to a
passive or "listen only" mode, and cannot be detected by any WIDS platform. For customers operating
in no-wireless environments, reconnaissance events are of medium to high importance, and should be
investigated. For deployments in urban multi-tenant areas reconnaissance events are of minor
importance, because of the increasing prevalence of wireless networks combined with the increasing
sophistication of newer reconnaissance tools that operate in passive mode and cannot be detected.
Reconnaissance Alarms are broken down into the following three sub-types:
• Reconnaissance Tools - Reconnaissance tools enable a user to discover available wireless devices in
the vicinity of the user running the tool. While early versions of these tools use active methods to
find available wireless resources, newer version are increasingly more sophisticated and have
transitioned to passive or listen only mode and will go undetected.
• Typical Client Activity - In wireless networking clients actively search for the wireless networks they
have been configured to connect to, enabling the clients to find the wireless APs that are in the
vicinity of the station. Once a client connects to an AP, it will continue to search for other resources,
which may include dierent networks or resources with a higher signal strength. Reconnaissance
activity in environments with deployed wireless networks is considered typical and is expected
behavior from devices.
•
Weakness - APs can be configured to make them more or less vulnerable to reconnaissance activity;
some of these options include broadcasting the SSID in beacon, and options to respond to null
probe requests. Configuring the AP to not respond to null probe requests and disable broadcasting
the beacon in the SSID is a good security practice, which hides the wireless network identify from
basic users, however it will do little to deter more advanced users attempting to discover the
wireless network.
Configuration
Tab Alarm Configuration
Extreme AirDefense User Guide for version 10.5. 627