An Efficient Scheduling Scheme for Assigning Transmission Opportunity in QoS-Guaranteed Wireless LAN

  • TAGASHIRA Shigeaki
    Graduate School of Information Science and Electrical Engineering, Kyushu University The Institute of Electronics, Information and Communication Engineers
  • YAMANE Masahiro
    Graduate School of Engineering, Hiroshima University
  • FUJITA Satoshi
    Graduate School of Engineering, Hiroshima University The Institute of Electronics, Information and Communication Engineers

Search this article

Abstract

The IEEE 802.11e standard defines several important techniques that guarantee the quality of service (QoS) of multimedia communications in wireless LAN applications. A key technique introduced in the standard is an efficient media access control based on the Hybrid Coordination Function (HCF), which assigns an appropriate transmission opportunity (TXOP) to each flow for satisfying several requirements on the flow, such as delay bound and communication bandwidth. Although the simple scheduler designed in HCF could provide an efficient tool to guarantee the QoS in wireless LAN applications, it has a serious drawback, wherein a useless bandwidth assignment frequently occurs. Such assignments occur primarily due to a limitation of the scheme, wherein all the flows share the same service interval (SI). In this paper, we propose a new scheduling scheme that associates each flow with its own SI according to the hardness of the required SI. The effect of this approach is experimentally evaluated by simulation, the results of which indicate that the number of admitted flows and network resource utilization increase due to the proposed scheme.

Journal

References(15)*help

See more

Details 詳細情報について

Report a problem

Back to top