Specifications

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Cisco IOS Software Configuration Guide for Cisco Aironet Access Points
OL-5260-01
Chapter 6 Configuring Radio Settings
Disabling and Enabling Aironet Extensions
Beginning in privileged EXEC mode, follow these steps to select the antennas the access point uses to
receive and transmit data:
Disabling and Enabling Aironet Extensions
By default, the access point uses Cisco Aironet 802.11 extensions to detect the capabilities of Cisco
Aironet client devices and to support features that require specific interaction between the access point
and associated client devices. Aironet extensions must be enabled to support 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.
• Cisco Key Integrity Protocol (CKIP)—Cisco's WEP key permutation technique based on an early
algorithm presented by the IEEE 802.11i security task group. The standards-based algorithm, TKIP,
does not require Aironet extensions to be enabled.
• Repeater mode—Aironet extensions must be enabled on repeater access points and on the root
access points to which they associate.
• World mode (legacy only)—Client devices with legacy world mode enabled receive carrier set
information from the access point and adjust their settings automatically. Aironet extensions are not
required for 802.11d world mode operation.
• Limiting the power level on associated client devices—When a client device associates to the access
point, the access point sends the maximum allowed power level setting to the client.
Disabling Aironet extensions disables the features listed above, but it sometimes improves the ability of
non-Cisco client devices to associate to the access point.
Command Purpose
Step 1
configure terminal Enter global configuration mode.
Step 2
interface dot11radio { 0 | 1 } Enter interface configuration mode for the radio interface. The
2.4-GHz radio is radio 0, and the 5-GHz radio is radio 1.
Step 3
antenna receive
{diversity | left | right}
Set the receive antenna to diversity, left, or right.
Note For best performance, leave the receive antenna setting
at the default setting, diversity.
Step 4
antenna transmit
{diversity | left | right}
Set the transmit antenna to diversity, left, or right.
Note For best performance, leave the transmit antenna
setting at the default setting, diversity.
Step 5
end Return to privileged EXEC mode.
Step 6
copy running-config startup-config (Optional) Save your entries in the configuration file.