TCP throughput efficiency enhancement in IEEE 802.11n network

Abstract

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-tosend/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.

A simulation study of video conferencing system over IEEE 802.11n Wireless LAN

“…It created in 1999 and deals with the 5GHz band. Networks, which used 802.11g operate at 2.4 GHz band, the same band as 802.11b, but the 802.11g uses OFDM technology that allows data rate speed to reach 54 Mbps [6][7][8].…”

“…The IEEE 802.11n standard was introduced in 2009. It is based on many accelerator technologies such as the Multiple Input Multiple Output (MIMO) technology, the frame aggregation, channel bonding, and the block acknowledgment mechanism to support high data rate [6]. IEEE802.11n operates on either the 2.4 GHz or the 5 GHz band, it supports two channel bandwidth 20MHz and 40MHz [6,7].…”

“…It is based on many accelerator technologies such as the Multiple Input Multiple Output (MIMO) technology, the frame aggregation, channel bonding, and the block acknowledgment mechanism to support high data rate [6]. IEEE802.11n operates on either the 2.4 GHz or the 5 GHz band, it supports two channel bandwidth 20MHz and 40MHz [6,7]. The IEEE 802.11n could support the data rate of 6.5Mbps in the case of the following conditions (20MHz channel, 800ns guard interval GI mode, and 1x1 MIMO technology) while the high level of 802.11n (600Mbps) is achieved under the following conditions (40MHz channel, 400ns guard interval GI mode, and 4x4 MIMO [9][10][11][12]8].…”