3com WXR100 3CRWXR10095A User Manual

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586
C
HAPTER
 26: R
OGUE
 D
ETECTION
 
AND
 C
OUNTERMEASURES
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Decrypt errors—An excessive number of decrypt errors can indicate 
that multiple clients are using the same MAC address. A device’s MAC 
address is supposed to be unique. Multiple instances of the same 
address can indicate that a rogue device is pretending to be a 
legitimate device by spoofing its MAC address. 
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Fake AP—A rogue device sends beacon frames for randomly 
generated SSIDs or BSSIDs. This type of attack can cause clients to 
become confused by the presence of so many SSIDs and BSSIDs, and 
thus interferes with the clients’ ability to connect to valid APs. This 
type of attack can also interfere with RF Auto-Tuning when a MAP is 
trying to adjust to its RF neighborhood. 
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SSID masquerade—A rogue device pretends to be a legitimate AP by 
sending beacon frames for a valid SSID serviced by APs in your 
network. Data from clients that associate with the rogue device can 
be accessed by the hacker controlling the rogue device.
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Spoofed AP—A rogue device pretends to be a 3Com MAP by sending 
packets with the source MAC address of the 3Com MAP. Data from 
clients that associate with the rogue device can be accessed by the 
hacker controlling the rogue device.
MSS detects a spoofed AP attack based on the fingerprint of the spoofed 
MAP. Packets from the real MAP have the correct signature, while 
spoofed packets lack the signature. (See “Enabling MAP Signatures” on 
page 582.)
Netstumbler and
Wellenreiter
Applications
Netstumbler and Wellenreiter are widely available applications that 
hackers can use to gather information about the APs in your network, 
including location, manufacturer, and encryption settings. 
Wireless Bridge
A wireless bridge can extend a wireless network outside the desired area. 
For example, someone can place a wireless bridge near an exterior wall to 
extend wireless coverage out into the parking lot, where a hacker could 
then gain access to the network. 
Ad-Hoc Network
An ad-hoc network is established directly among wireless clients and 
does not use the infrastructure network (a network using an AP). An 
ad-hoc network might not be an intentionally malicious attack on the 
network, but it does steal bandwidth from your infrastructure users.