Research Article
Enhanced Bandwidth Allocation for TCP Flows in WiMAX Networks
@INPROCEEDINGS{10.1007/978-3-642-10625-5_23, author={Eun-Chan Park and Chunyu Hu and Hwangnam Kim}, title={Enhanced Bandwidth Allocation for TCP Flows in WiMAX Networks}, proceedings={Quality of Service in Heterogeneous Networks. 6th International ICST Conference on Heterogeneous Networking for Quality, Reliability, Security and Robustness, QShine 2009 and 3rd International Workshop on Advanced Architectures and Algorithms for Internet Delivery and Applications, AAA-IDEA 2009, Las Palmas, Gran Canaria, November 23-25, 2009 Proceedings}, proceedings_a={QSHINE}, year={2012}, month={10}, keywords={IEEE 802.16e MAC bandwidth request \& allocation TCP performance}, doi={10.1007/978-3-642-10625-5_23} }- Eun-Chan Park
Chunyu Hu
Hwangnam Kim
Year: 2012
Enhanced Bandwidth Allocation for TCP Flows in WiMAX Networks
QSHINE
Springer
DOI: 10.1007/978-3-642-10625-5_23
Abstract
In this paper, we propose a bandwidth-allocation mechanism to improve TCP performance in the IEEE 802.16 WiMAX networks. According to the IEEE 802.16 standard, when serving a downlink TCP flow, the transmission of the uplink ACK, which is performed over a separate unidirectional connection, incurs additional bandwidth-request/allocation delay. Thus, it increases the round trip time of the downlink TCP flow and results in the decrease of throughput accordingly. First, we derive an analytical model to investigate the effect of the uplink bandwidth-request/allocation delay on the downlink TCP throughput. Second, we propose a simple, yet effective, bidirectional bandwidth-allocation mechanism that couples the bandwidth allocation for uplink and downlink connections by using either or . The proposed scheme reduces unnecessary bandwidth-request delay and the relevant signaling overhead due to proactive allocation; meanwhile, it maintains high efficiency of uplink bandwidth usage by using piggyback request. Moreover, our proposed scheme is quite simple and practical; it can be simply implemented in the base station without requiring any modification in the subscriber stations or resorting to any cross-layer signaling mechanisms. The simulation results ascertain that the proposed approach significantly increases the downlink TCP throughput and the uplink bandwidth efficiency.