Distributed QoS Guarantees for Realtime Traffic in Ad Hoc Networks

In this paper, we propose a new cross-layer framework, named QPART ( QoS br>rotocol for Adhoc Realtime Traffic), which provides QoS guarantees to real-time multimedia applications for wireless ad hoc networks. By adapting the contention window sizes at the MAC layer, QPART schedules packets of flows according to their unique QoS requirements. QPART implements priority-based admission control and conflict resolution to ensure that the requirements of admitted realtime flows is smaller than the network capacity. The novelty of QPART is that it is robust to mobility and variances in channel capacity and imposes no control message overhead on the network

Enabling limited traffic scheduling in asynchronous ad hoc networks

We present work-in-progress developing a communication framework that addresses the communication challenges of the decentralized multihop wireless environment. The main contribution is the combination of a fully distributed, asynchronous power save mechanism with adaptation of the timing patterns defined by the power save mechanism to improve the energy and bandwidth efficiency of communication in multihop wireless networks. The possibility of leveraging this strategy to provide more complex forms of traffic management is explored

Service differentiation in multihop wireless packet networks

This work explores the potential of link layer scheduling combined with MAC layer prioritization for providing service differentiation in multihop wireless packet networks. As a result of limited power, multihop characteristic and mobility, packet loss ratio in wireless ad hoc networks tends to be high compared to wireline and one-hop mobile data networks. Therefore, for wireless ad hoc networks, DiffServ-like distributed service differentiation schemes are more viable than hard QoS solutions, which are mainly designed for wireline networks. The choice and implementation of proper queuing and scheduling methods, which determine how packets will use the channel when bandwidth becomes available, contributes significantly to this differentiation. Due to the broadcast nature of wireless communication, media access is one of the main resources that needs to be shared among different flows. Thus, one can design and implement algorithms also at MAC level for service differentiation. In this study, in addition to the scheduling discipline, IEEE 802.11 Distributed Coordination Function is used to increase the media access probability of a specific class of traffic. It is shown that the service requirements of a class can be better met using this two level approach compared to the cases where either of these schemes used alone

Recent advances in radio resource management for heterogeneous LTE/LTE-A networks

As heterogeneous networks (HetNets) emerge as one of the most promising developments toward realizing the target specifications of Long Term Evolution (LTE) and LTE-Advanced (LTE-A) networks, radio resource management (RRM) research for such networks has, in recent times, been intensively pursued. Clearly, recent research mainly concentrates on the aspect of interference mitigation. Other RRM aspects, such as radio resource utilization, fairness, complexity, and QoS, have not been given much attention. In this paper, we aim to provide an overview of the key challenges arising from HetNets and highlight their importance. Subsequently, we present a comprehensive survey of the RRM schemes that have been studied in recent years for LTE/LTE-A HetNets, with a particular focus on those for femtocells and relay nodes. Furthermore, we classify these RRM schemes according to their underlying approaches. In addition, these RRM schemes are qualitatively analyzed and compared to each other. We also identify a number of potential research directions for future RRM development. Finally, we discuss the lack of current RRM research and the importance of multi-objective RRM studies

Scheduling for Optimal Rate Allocation in Ad Hoc Networks With Heterogeneous Delay Constraints

This paper studies the problem of scheduling in single-hop wireless networks with real-time traffic, where every packet arrival has an associated deadline and a minimum fraction of packets must be transmitted before the end of the deadline. Using optimization and stochastic network theory we propose a framework to model the quality of service (QoS) requirements under delay constraints. The model allows for fairly general arrival models with heterogeneous constraints. The framework results in an optimal scheduling algorithm which fairly allocates data rates to all flows while meeting long-term delay demands. We also prove that under a simplified scenario our solution translates into a greedy strategy that makes optimal decisions with low complexity

Wireless measurement Scheme for bandwidth Estimation in Multihop Wireless Adhoc network

The necessity to bear real time and multimedia application for users of Mobile 1D468;1D485;1D489;1D490;1D484; Network (1D474;1D468;1D475;1D46C;1D47B;) is becoming vital. Mobile 1D468;1D485;1D489;1D490;1D484; network facilitates decentralized network that can present multimedia users with mobility that they have demanded, if proficient 1D478;1D490;1D47A; multicast strategies were developed. By giving the guarantee of 1D478;1D490;1D47A; in 1D468;1D485;1D489;1D490;1D484; network, the proficient bandwidth estimation method plays a very important role. The research paper represented here presents a splendid method for estimating or measuring Bandwidth in 1D468;1D485;1D489;1D490;1D484; network whose character is decentralized in nature. Contrasting in the centralized formation, the bandwidth estimating in 1D468;1D485;1D489;1D490;1D484; is significant and this eventually makes an influence over the 1D478;1D490;1D47A; of the network communication. The admission control and dynamic bandwidth management method which is presented here, facilitates it with fairness and rate guarantees despite the distributed link layer fair scheduling being absent. Alteration has been made over 1D474;1D468;1D46A; layer and this method is appropriate where the peer-to-peer (1D477;1D7D0;1D477;) multimedia transmissions rates are amended in compliantly fashion.In the research work presented here the architecture of the 1D474;1D468;1D46A; layer has been altered and the data handling capacity has been increased. This technique is adopted to facilitate higher data rate transmission and eliminate congestion over the considerednetwork. The proposed technique implements the splitting of 1D474;1D468;1D46A; into two sub layer where one will be responsible for control data transmission while other effectively transmits the data bits. Thus it results into higher data rate transmission with better accuracy and optimized network throughput. The research work in the presented paper exhibits superior accuracy and is very much effective in bandwidth estimation and management application in multi hop Mobile Ad-H