Lisa, an administrator, has set up an 802.11n wireless network. Users with 802.11n laptops have reported that speeds are slow. After testing, Lisa determines that users max out at 802.11g speeds…

The IEEE 802.11n standard requires WMM (based on 802.11e QoS) to be enabled as a precondition for activating high-throughput (HT) mode. When WMM is disabled, the AP reverts to legacy mode and caps throughput at approximately 54 Mbps - the 802.11g maximum - even though the hardware is capable of much higher speeds. Enabling WMM allows the AP to negotiate HT rates with compatible clients.

Using 40 MHz channels in the 2.4 GHz band would increase bandwidth but causes significant interference with neighboring networks and is generally not the root fix when WMM is the real missing prerequisite.

Access point antenna isolation is not a standard configurable feature in typical consumer or enterprise APs and would not address speed limitations.

Limiting clients to 802.11g would reduce speeds further rather than resolve the issue - the goal is to achieve 802.11n speeds, not cap them.