Cisco Systems OL-6415-04 manual Disabling and Enabling Access Point Extensions

Chapter 2 Configuring Radio Settings

Disabling and Enabling Access Point Extensions

Disabling and Enabling Access Point Extensions

By default, the wireless device uses Cisco Access Point extensions to detect the capabilities of

Cisco Access Point client devices and to support features that require specific interaction between the wireless device and associated client devices. Cisco Access Point extensions must be enabled to support these features:

•Load balancing—The wireless device uses Access Point 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 wireless device and all associated client devices, adds a few bytes to each packet to make the packets tamper-proof.

•World mode (legacy only)—Client devices with legacy world mode enabled receive carrier set information from the wireless device and adjust their settings automatically. Access Point 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 wireless device, the wireless device sends the maximum allowed power level setting to the client.

Disabling Access Point extensions disables the features listed above, but it sometimes improves the ability of other companies devices to associate to the wireless device.

Access Point extensions are enabled by default. Beginning in privileged EXEC mode, follow these steps to disable Access Point extensions:

	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
	no dot11 extension aironet	Disable Access Point extensions.
Step 4
	end	Return to privileged EXEC mode.
Step 5
	copy running-config startup-config	(Optional) Save your entries in the configuration file.

Use the dot11 extension aironet command to enable Access Point extensions if they are disabled.

Configuring the Ethernet Encapsulation Transformation Method

When the wireless device receives data packets that are not 802.3 packets, the wireless device must format the packets to 802.3 using an encapsulation transformation method. These are the two transformation methods:

•802.1H—This method provides optimum performance for Cisco Access Point wireless products. This is the default setting.

•snap—Use this setting to ensure interoperability with non-Cisco Access Point wireless equipment. RFC1042 does not provide the interoperability advantages of 802.1H but is used by other manufacturers of wireless equipment. This is the default setting.

Cisco Wireless ISR and HWIC Access Point Configuration Guide

OL-6415-04 2-23