tailieunhanh - Báo cáo hóa học: " Research Article Size-Based and Direction-Based TCP "

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Size-Based and Direction-Based TCP | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2010 Article ID818190 16 pages doi 2010 818190 Research Article Size-Based and Direction-Based TCP Fairness Issues in IEEE WLANs Naeem Khademi1 and Mohamed Othman2 1 Department of Informatics University of Oslo P. O. Box 1080 Blindern N-0314 Oslo Norway 2 Department of Communication Technology and Network Faculty of Computer Science and Information Technology Universiti Putra Malaysia Serdang Selangor D. E. 43400 Malaysia Correspondence should be addressed to Naeem Khademi naeemk@ Received 14 January 2010 Revised 3 June 2010 Accepted 20 July 2010 Academic Editor Kwan L. Yeung Copyright 2010 N. Khademi and M. Othman. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. Cross-layer interaction of Distributed Coordination Function DCF of MAC protocol and TCP transport protocol leads to two types of unfairness. In a mixed traffic scenario short-lived TCP flows suffer from poor performance compared to the aggressive long-lived flows. Since the main source of Internet traffic is small file web transfers this issue forms a major challenge in current WLANs which is called size-based unfairness. In addition when sharing an access point bottleneck queue upstream flows impede the performance of downstream flows resulting in direction-based unfairness. Proposed solutions in the literature mostly rely on size-based scheduling policies. However each proposed method is able to solve any of these two mentioned aspects none of them can provide both size-based and direction-based fairness in a unique solution. In this paper we propose a novel queue management policy called Threshold-Based Least Attained Service-Selective Acknowledgment Filtering TLAS-SAF . We show analytically and by simulation that .