The service differentiation and adaptation are the important mechanisms for enhancing the performance of IEEE 802.11wireless local area networks (WLANs). However, all these mechanisms will have limitations for dealing high bandwidth streaming applications. The service differentiation technique proposed in IEEE 802.11e [4] mainly considers the signal with higher priority values to access the wir...

The vision of safer transportation is strongly driven by the introduction of Vehicular Safety Communications (VSC) to enable new cooperative safety applications. In highly dense traffic scenarios, however, the current Dedicated Short Range Communications (DSRC) technology is expected to face serious performance problems due to simultaneous transmissions making packets to collide with each other...

IEEE 802.11 is the most popular standard used in Wireless Local Area Networks (WLANs). Several Markov chain models have been developed to evaluate and to enhance the performance of the IEEE 802.11 Distributed Coordination Function (DCF) protocol. However, the existing models cannot accurately predict the performance of the network. Also, the existing models suffer with high packet collisions re...

Traditional TCP cannot detect link contention losses and route failure losses which occur in MANET and considers every packet loss as congestion. This results in severe degradation of TCP performance. In this research work, we modified the operations of TCP to adapt to network states. The cross-layer notifications are used for adapting the congestion window and achieving better performance. We ...

The most significant issue in 802.11 contention based networks is to prevent collisions and to ensure connection quality. Researchers have shown an increased interest in collision aware back-off algorithms. However, collision aware back-off algorithms are still failed to ensure strict priority for the high priority traffic. Especially in the heavy loading network, a large number of unsuccessful...

Design of efficient medium access control (MAC) protocols with both high throughput performance and highdegree of fairness performance is a major focus in distributed contention-based MAC protocol research. In this paper, we propose a novel and efficient contention-based MAC protocol for wireless local area networks, namely, the Fast Collision Resolution (FCR) algorithm. This algorithm is devel...

This paper proposes a contention-based fair coexistence mechanism among heterogeneous networks that have different transmission power and/or coverage. First, we show that the existing carrier sensing multiple access (CSMA) mechanism, that is a prevailing contention-based protocol, results in significant unfairness in channel access when heterogeneous networks coexist; a system with lower transm...

The distributed coordination function (DCF) is the most widely deployed medium access control (MAC) protocol for IEEE 802.11 WLANs. It is a carrier sense multiple access with collision avoidance (CSMA/CA) scheme which employs a binary exponential backoff (BEB) algorithm to reduce the collision probability. In this paper we propose a novel backoff algorithm, collision-aware backoff mechanism (CA...

The IEEE 802. 15. 6 is a new communication standard on Wireless Body Area Network (WBAN) for short-range, wireless communications in the vicinity of, or inside a human body. It is used for medical and non-medical applications. The IEEE 802. 15. 6 draft defines a Medium Access Control (MAC) layer compatible with several Physical layers (PHY), it also specifies two main channel access modes; cont...

In this paper, we propose a new solution to cope with the unfairness limitations of the Distributed Coordination Function (DCF) algorithm. Indeed, in current widely deployed IEEE 802.11b Wireless Local Area Networks (WLAN), the performance of all the competing access nodes are dramatically affected once the bit rate of one station degrades. This anomaly is due to the unfairness behavior of the ...