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Cisco Aironet 1200 Series Access Point Software Configuration Guide
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Chapter 3 Configuration
Radio Configuration
Use Aironet Extensions
Select
yes
or
no
to use Cisco Aironet 802.11 extensions. This setting must be set
to
yes
(the default setting) to enable these features:
•
Load balancing—The access point uses Aironet extensions to direct client
devices to an access point that provides the best connection to the network
based on factors such as number of users, bit error rates, and signal strength.
•
Message Integrity Check (MIC)—MIC is an additional WEP security feature
that prevents attacks on encrypted packets called
bit-flip
attacks. The MIC,
implemented on both the access point and all associated client devices, adds
a few bytes to each packet to make the packets tamper-proof.
•
Temporal Key Integrity Protocol (TKIP)—TKIP, also known as WEP key
hashing, is an additional WEP security feature that defends against an attack
on WEP in which the intruder uses an unencrypted segment called the
initialization vector (IV) in encrypted packets to calculate the WEP key.
•
Repeater mode—You must set Use Aironet Extensions to yes if the access
point is set up as a repeater or if it communicates with a repeater.
The extensions also improve the access point’s ability to understand the
capabilities of Cisco Aironet client devices associated with the access point.
Classify Workgroup Bridges as Network Infrastructure
Select
no
to allow more than 20 Cisco Aironet Workgroup Bridges to associate to
the access point. The default setting,
yes
, limits the number of workgroup bridges
that can associate to the access point to 20 or less.
Access points and bridges normally treat workgroup bridges not as client devices
but as infrastructure devices, like access points or bridges. Treating a workgroup
bridge as an infrastructure device means that the access point reliably delivers
multicast packets, including Address Resolution Protocol (ARP) packets, to the
workgroup bridge.
The performance cost of reliable multicast delivery—duplication of each
multicast packet sent to each workgroup bridge—limits the number of
infrastructure devices, including workgroup bridges, that can associate to the
access point. To increase beyond 20 the number of workgroup bridges that can
associate to the access point, the access point must reduce the delivery reliability
of multicast packets to workgroup bridges. With reduced reliability, the access
point cannot confirm whether multicast packets reach the intended workgroup
