ISU Electrical and Computer Engineering Archives

High-Performance Distributed Coordination Function (HDCF) for Wireless LANs

Al-Mefleh, Haithem and Chang, Morris (2006) High-Performance Distributed Coordination Function (HDCF) for Wireless LANs. Publisher UNSPECIFIED.

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IEEE 802.11 wireless local area networks (WLANs) are becoming more popular. The performance of 802.11 DCF (Distributed Coordination Function), that is the basic MAC scheme used in wireless devices, degrades especially under larger network sizes, and higher loads due to higher contention and so more idle slots and higher collision rates. We propose a new high-performance DCF (HDCF) scheme that achieves a higher and more stable performance while providing fair access among all users. In HDCF, the transmitting stations randomly select who is the next transmitter and so active stations do not have to contend for the channel, and an interrupt scheme is used by newly transmitting stations without contending with the existing active stations. As a result, HDCF achieves collision avoidance and fairness without idle slots added by the backoff algorithm used in DCF. For evaluation, we provide an analytical model to discuss different issues of HDCF. Also, we utilize Opnet Modeler to provide simulation that considers both saturated and nonsaturated stations. The results show that HDCF outperforms DCF in terms of throughput, and long-term and short-term fairness. The simulations show gains up to 391.2% of normalized throughput and 26.8% of fairness index.

EPrint Type:Technical Report
Subjects:Computer Engineering > INFORMATION SYSTEMS SECURITY & NETWORKING > Computer Networking and Security
ID Code:364
Identification Number:Identification Number UNSPECIFIED
Deposited By:Haithem Al-Mefleh A
Deposited On:28 August 2007

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