This paper presents a sender side only TCP mechanism to prevent compromise for bandwidth utilization in IEEE 802.11 wireless networks. In absence of mechanism for accurate and immediate loss discrimination, the TCP se...This paper presents a sender side only TCP mechanism to prevent compromise for bandwidth utilization in IEEE 802.11 wireless networks. In absence of mechanism for accurate and immediate loss discrimination, the TCP sender unnecessarily reduces its Loss Window in response to the packet losses due to transmission errors. At the same time, frequent transmission losses and associated link retransmissions cause inaccuracy for available bandwidth estimate. The proposal, Adaptive TCP tackles the above issues using two refinements. First, sender estimates the degree of congestion by exploiting the statistics for estimated Round Trip Time (RTT). With this, it prevents unnecessary shrinkage of Loss Window and bandwidth estimate. Second, by concluding the uninterrupted evolution of its sending rate in recent past, the Adaptive TCP advances bandwidth estimate under favorable network conditions. This in turn, facilitates for quick growth in TCP’s sending rate after loss recovery and consequently alleviates bandwidth utilization. The authors implement the algorithm on top of TCP NewReno, evaluate and compare its performance with the wireless TCP variants deployed in current Internet. Through intensive simulations it is demonstrated that the Adaptive TCP outperforms other well-established TCP variants, and yields more than 100% of the throughput performance and more than 60% of improvement for bandwidth utilization, compared to TCP NewReno. The simulation results also demonstrated compatibility of Adaptive TCP in a shared wireless environment.展开更多
TCP(Transmission Control Protocol)是Internet中一种可靠的传输层协议,旨在为互联网提供一种可靠的端到端的字节传输流。最初是为有线环境设计的,在无线通信中引入TCP技术后,由于原有的TCP技术不能很好地适应无线通信高误码、长时延...TCP(Transmission Control Protocol)是Internet中一种可靠的传输层协议,旨在为互联网提供一种可靠的端到端的字节传输流。最初是为有线环境设计的,在无线通信中引入TCP技术后,由于原有的TCP技术不能很好地适应无线通信高误码、长时延等特点,导致传输性能不够理想。因此无线通信系统引入了TPE(TCP Performance Enhancer,TCP性能增强技术)技术,旨在提升传输性能。对TPE策略进行了研究,越是覆盖较差,小流量业务越多的区域,TPE的优化效果越明显,进而提出了一套有效改善网络速率的TPE参数配置方案。展开更多
文摘This paper presents a sender side only TCP mechanism to prevent compromise for bandwidth utilization in IEEE 802.11 wireless networks. In absence of mechanism for accurate and immediate loss discrimination, the TCP sender unnecessarily reduces its Loss Window in response to the packet losses due to transmission errors. At the same time, frequent transmission losses and associated link retransmissions cause inaccuracy for available bandwidth estimate. The proposal, Adaptive TCP tackles the above issues using two refinements. First, sender estimates the degree of congestion by exploiting the statistics for estimated Round Trip Time (RTT). With this, it prevents unnecessary shrinkage of Loss Window and bandwidth estimate. Second, by concluding the uninterrupted evolution of its sending rate in recent past, the Adaptive TCP advances bandwidth estimate under favorable network conditions. This in turn, facilitates for quick growth in TCP’s sending rate after loss recovery and consequently alleviates bandwidth utilization. The authors implement the algorithm on top of TCP NewReno, evaluate and compare its performance with the wireless TCP variants deployed in current Internet. Through intensive simulations it is demonstrated that the Adaptive TCP outperforms other well-established TCP variants, and yields more than 100% of the throughput performance and more than 60% of improvement for bandwidth utilization, compared to TCP NewReno. The simulation results also demonstrated compatibility of Adaptive TCP in a shared wireless environment.
文摘TCP(Transmission Control Protocol)是Internet中一种可靠的传输层协议,旨在为互联网提供一种可靠的端到端的字节传输流。最初是为有线环境设计的,在无线通信中引入TCP技术后,由于原有的TCP技术不能很好地适应无线通信高误码、长时延等特点,导致传输性能不够理想。因此无线通信系统引入了TPE(TCP Performance Enhancer,TCP性能增强技术)技术,旨在提升传输性能。对TPE策略进行了研究,越是覆盖较差,小流量业务越多的区域,TPE的优化效果越明显,进而提出了一套有效改善网络速率的TPE参数配置方案。
