This paper presents the delay analysis for buffered Aloha networks with K-Exponential Backoff. Mean access delay and mean queueing delay are derived and demonstrated via the examples of Geometric Retransmission (K=1) and Exponential Backoff (K=∞). The comparison shows that higher delay is incurred with Geometric Retransmission when the aggregate input rate is small, and the delay gap is enlarge...

Network coding is a promising technique for improving system performance in wireless multihop networks. In this paper, the throughput and fairness in single-relay multi-user wireless networks are evaluated. The carrier sense multiple access with collision avoidance (CSMA/CA) protocol and network coding are used in the medium access control (MAC) sublayer in such networks. The fairness of wirele...

Neighbor Discovery and Link Estimation (NDLE) phase and Collection Tree Construction (CTC) phase are essential for correct and efficient operation of network protocols. However, the accuracy of these phases is highly affected by packet collisions, because CSMA is used for access arbitration and it does not support collision avoidance with broadcast transmissions. To improve NDLE accuracy: (i) W...

We investigate the problem of efficient resource control for elastic traffic in IEEE 802.11e’s Enhanced Distributed Channel Access (EDCA) mechanism. Our approach considers an economic modelling framework based on congestion pricing that captures how various factors, such as the probability of attempting to transmit a frame, the use of the basic CSMA/CA or the RTS/CTS procedure, and the physical...

Advanced Infrared (AIr) is a suggested framework for Infrared Data Association (IrDA) for interior infrared LANs. Advanced Infrared (AIr) is the standard MAC prototype for wireless infrared LANs and is capable to assist point to multiple point transaction although it is not precisely constructed for such prototypes. A back off approach is a methodology for the wireless system MAC layer protocol...

This paper studies TCP performance over static, ad hoc networks that use IEEE 802.11 protocol as the access method. Our study reveals some interesting results. First, there exists an optimal value for TCP congestion window size, at which the TCP throughput is maximized. However, TCP does not operate around this optimal point, and typically grows its window much larger; this leads to decreased t...

With the provisioning of high-speed wireless LAN (WLAN) environments, multimedia services (e.g., VoIP and video-conference) with different QoS requirements will be available in next generation WLANs. Multimedia services could be categorized into multiple traffic classes and different priorities will be applied to access the wireless medium. The IEEE 802.11 working group has been developing a ne...

Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) is probably the most widespread multiple access protocol in use today, mainly due to the tremendous success of the IEEE 802.11 suite of standards. Until now most of the studies done about the protocol have focused on maximizing the performance. However as the bands become more crowded and the user terminals become easier to reconf...

IEEE 802.11 based network analysis has been largely focused on throughput performance. There has been a growing concern to provide quality of service (QoS) to this protocol suite, the result of which has been the considerable work towards the formulation of the IEEE 802.11e and IEEE 802.11n versions. One important aspect to consider is performance for real time applications like voice over IP (...

Distributed coordination function (DCF) scheme is the basic mechanism of MAC layer in 802.11 standards. The element which controls the access to the channel is the value of Contention Window (CW). There is a process of this value management and the value of Contention Window is very important from the point of view of transmission Quality of Service parameters, especially the average throughput...