CBA-TCP: A cross-layer TCP transmission rate adaptation scheme based on the compressed block ACK bitmap of IEEE 802.11n networks

Abstract

Optimizing the performance of TCP in wireless networks in a changing network condition is a highlychallenging issue. The lack of information at the TCP layer about the link quality will result in inaccuratetransmission rate. Therefore, TCP needs to have sufficient information about the environment and thedifferent characteristics of the lower layers to improve the performance. To achieve this goal we proposed across-layer scheme which makes use of the information stored in the 802.11n compressed block acknowledgedbitmap about the status of the transmitted subframes of the aggregated frame. This information is fed to theTCP transmission mechanism as a new criterion to adjust the TCP transmission rate with accordance to theaggregation level and channel quality. The simulation results show that the proposed scheme improves theTCP performance in term of throughput and packet loss.

Keywords

• adaptive tcp
• compressed block ack
• congestion window
• cross-layering
• ieee 802.11ac
• ieee 802.11n