Performance study of IEEE 802.11n WLANs

The IEEE 802.11b/g based wireless LANs (WLANs) are widely deployed across enterprise and home segments. The new IEEE 802.11n amendment aims at providing data rates up to 600 Mbps with better quality of service (QoS) and backward compatibility with all the legacy (IEEE 802.11a/b/g) devices. These legacy devices cannot decode 802.11n transmissions and hence all the 802.11n transmissions must follow a protection mechanism when such legacy clients are present. These protection mechanisms ensure that the legacy stations are aware of 802.11n transmissions and do not interfere with it. The cost for achieving this protection is the throughput degradation in 802.11n. This paper presents a detailed simulation study of the MAC throughput impact due to the usage of protection mechanisms in the 802.11n network. Our simulation study will cover various deployment scenarios of 802.11n which will lead to different protection mechanisms being used. Results presented will highlight the potential impact of protection on the performance of 802.11n WLANs.