How disabling 802.11b data rates helps improve your Wi-Fi performance.

A couple weeks ago, I did a WLAN audit at a large MNC’s office in Bangkok. They were looking for a helping hand optimizing their existing Wi-Fi deployments.

It’s very common to find design flaws or misconfigurations like using channel 3 or opting for 80MHz width in high-density locations. But an area that many WLAN operators often overlook is the minimum basic rate (MBR).

MBR is the lowest data rate that AP uses for all its broadcast frames like Beacon. Wi-Fi sends a lot, I mean a LOT of broadcasts, which potentially takes up a big chunk of your precious airtime. The impact becomes even more pronounced in high-density environments where many APs and devices are competing for opportunities to transmit.

This is where choosing correct MBR helps soften the blow. The idea is using high MBR helps clear the broadcast frames faster. So by simply disabling the legacy 802.11b data rates (1, 2, 5.5, 11Mbps), and use 6Mbps or even 12Mbps OFDM MBR will improve your Wi-Fi performance.

Whether or not you can change your MBR depends on your Wi-Fi vendors. Most enterprise brands allow you to fine tune MBR directly from the controller; but if you are using SMB or consumer-APs, chances are you don’t have that level of control, so you’ll have to optimize your WLAN in other ways.