Improving Protocol Capacity with Model-Based Frame Scheduling in IEEE 802.11-operated WLANs

Hwangnam Kim, Jennifer C. Hou

Research output: Contribution to conferencePaper

69 Citations (Scopus)

Abstract

In this paper, we develop a model-based frame scheduling scheme, called MFS, to enhance the capacity of IEEE 802.11-operated wireless LANs (WLANs). In MFS each node estimates the current network status by keeping track of the number of collisions it encounters between its two consecutive successful frame transmissions, and, based on the the estimated information, computes the current network utilization. The result is then used to determine a scheduling delay that is introduced (with the objective of avoiding collision) before a node attempts for transmission of its pending frame. In order to accurately calculate the current utilization in WLANs, we develop an analytical model that characterizes data transmission activities in IEEE 802.11-operated WLANs with/without the RTS/CTS mechanism, and validate the model with ns-2 simulation. All the control overhead incurred in the physical and MAC layers, as well as system parameters specified in IEEE 802.11 are figured in. We have conducted a comprehensive simulation study to evaluate MFS in perspective of number of collisions, achievable throughput, and inter-transmission delay. The simulation results indicate that the performance improvement with respect to protocol capacity can be as high as 20% with RTS/CTS and 150% without RTS/CTS, in a WLAN of up to 300 nodes. In addition, the inter-transmission delay in MFS is smaller and exhibits less variation than that in IEEE 802.11.

Original languageEnglish
Pages190-204
Number of pages15
Publication statusPublished - 2003 Dec 1
EventProceedings of the Ninth Annual International Conference on Mobile Computing and Networking, MobiCom 2003 - San Diego, CA., United States
Duration: 2003 Sep 142003 Sep 19

Other

OtherProceedings of the Ninth Annual International Conference on Mobile Computing and Networking, MobiCom 2003
CountryUnited States
CitySan Diego, CA.
Period03/9/1403/9/19

Keywords

  • IEEE 802.11
  • Performance analysis
  • Protocol enhancement
  • Wireless LANs (WLANs)

ASJC Scopus subject areas

  • Software
  • Hardware and Architecture
  • Computer Networks and Communications

Cite this

Kim, H., & Hou, J. C. (2003). Improving Protocol Capacity with Model-Based Frame Scheduling in IEEE 802.11-operated WLANs. 190-204. Paper presented at Proceedings of the Ninth Annual International Conference on Mobile Computing and Networking, MobiCom 2003, San Diego, CA., United States.