TCP throughput efficiency enhancement in IEEE 802.11n 

The new opportunities opened up by wireless technologies are also accompanied with new technical challenges. Principal among the challenges is the fact that wireless medium has limited bandwidth resources when compared with wired equivalent. The convenience brought about by the IEEE 802.11n protocol is also followed by the technical challenge of near average performance of the widely used transport control protocol (TCP) due to limited bandwidth resources of the wireless medium. IEEE 802.11n specifies standard for physical (PHY) and MAC layers of wireless local area networks (WLANs) which is based on the IEEE 802.11-2007 networking reference standard. This work is meant to enhance the efficiency of TCP in IEEE 802.11n network in order to improve per user bandwidth.

ACK suppression in both downstream and upstream TCP flow is used to improve bandwidth. The network bandwidth of an IEEE 802.11n LAN is simulated under two access methods; request-to-send/clear-to-send (RTS/CTS) access method and the basic method. Results showed an improvement in throughput efficiency over 10 nodes, which demonstrate performance improvement of TCP ACK suppression as 50% in comparison with receiver policy of acknowledging every TCP data segment and approximately 20% when compared with receiver’s policy of acknowledging every TCP data segment in the network. Simulation was conducted in Matlab R2012a.