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802.11g devices are rated to run at 54 Mbps, while 802.11b devices are rated to run at 11 Mbps. When the access point is servicing both 802.11b and 802.11g devices, the access point is said to be operating in mixed mode. Mixed mode results in 802.11g devices being slowed down in order to service both types of devices without problems. Clear to Send (CRT) protection is set by default to operate when both types of devices are connecting and this overhead reduces throughput.
The performance of the 802.11g devices can be maximized by blocking 802.11b devices from connecting to the access point.
This document explains how to block 802.11b devices from connecting on WAP200E.
Prevent 802.11b Devices From Connecting
Step 1. Access the graphical user interface of the access point and choose Wireless > Advanced Settings. The Advanced Wireless Settings page opens.
Step 2. Select G Only from the BSSBasicRateSet drop-down list to only allow 802.11g rates to be used on the access point.
Step 3. Click Save to have the settings go into immediate effect.