Adaptive Quality Of Service Call Admission Control With User Mobility Prediction For Multimedia Traffic Over Wireless Networks

Multimedia traffic is expected to be supported in the next generation wireless networks. As in wireline networks, the wireless network must also be capable of providing guaranteed quality of service (QoS) over the lifetime of mobile connections. Some challenging problems that appear in multimedia wireless networks, such as user mobility and shortage of bandwidth, influence the QoS provisioning for the users. In this thesis, we propose a new framework called Adaptive quality of service (AdQoS) to guarantee the QoS of multimedia traffic. The objectives that AdQoS framework tries to accomplish are minimum new call blocking and handoff dropping rates. The key feature of this framework is the bandwidth reallocation scheme. This scheme is developed to control the bandwidth operation of ongoing connections when the system is overloaded. The other key feature is the bandwidth reservation scheme incorporating a user mobility prediction to manage the QoS of the networks. Based on the mobility prediction, bandwidth is reserved to guarantee the uninterrupted hand off process. A comparison between existing user mobility prediction and the proposed scheme is also presented. An integrated system, which combines the Bandwidth Allocation Level technique and the user mobility prediction, is also proposed. The proposed user mobility prediction algorithm integrates the Received Signal Strength (RSS) measurements for the mobile terminal's intra-cell movement and aggregate history of mobile terminals for inter-cell movement. When compared with the conventional scheme proposed in the literature, the simulation results show that our proposed scheme reduces the new call blocking probabilities, the handoff dropping probabilities and reduces significantly the probability of terminating calls while still maintaining efficient bandwidth usage

Predictability of Wlan Mobility and Its Effects on Bandwidth Provisioning

Wireless local area networks (WLANs) are emerging as a popular technology for access to the Internet and enterprise networks. In the long term, the success of WLANs depends on services that support mobile network clients. \par Although other researchers have explored mobility prediction in hypothetical scenarios, evaluating their predictors analytically or with synthetic data, few studies have been able to evaluate their predictors with real user mobility data. As a first step towards filling this fundamental gap, we work with a large data set collected from the Dartmouth College campus-wide wireless network that hosts more than 500 access points and 6,000 users. Extending our earlier work that focuses on predicting the next-visited access point (i.e., location), in this work we explore the predictability of the time of user mobility. Indeed, our contributions are two-fold. First, we evaluate a series of predictors that reflect possible dependencies across time and space while benefiting from either individual or group mobility behaviors. Second, as a case study we examine voice applications and the use of handoff prediction for advance bandwidth reservation. Using application-specific performance metrics such as call drop and call block rates, we provide a picture of the potential gains of prediction. \par Our results indicate that it is difficult to predict handoff time accurately, when applied to real campus WLAN data. However, the findings of our case study also suggest that application performance can be improved significantly even with predictors that are only moderately accurate. The gains depend on the applications\u27 ability to use predictions and tolerate inaccurate predictions. In the case study, we combine the real mobility data with synthesized traffic data. The results show that intelligent prediction can lead to significant reductions in the rate at which active calls are dropped due to handoffs with marginal increments in the rate at which new calls are blocked

Evaluating Mobility Predictors in Wireless Networks for Improving Handoff and Opportunistic Routing

We evaluate mobility predictors in wireless networks. Handoff prediction in wireless networks has long been considered as a mechanism to improve the quality of service provided to mobile wireless users. Most prior studies, however, were based on theoretical analysis, simulation with synthetic mobility models, or small wireless network traces. We study the effect of mobility prediction for a large realistic wireless situation. We tackle the problem by using traces collected from a large production wireless network to evaluate several major families of handoff-location prediction techniques, a set of handoff-time predictors, and a predictor that jointly predicts handoff location and time. We also propose a fallback mechanism, which uses a lower-order predictor whenever a higher-order predictor fails to predict. We found that low-order Markov predictors, with our proposed fallback mechanisms, performed as well or better than the more complex and more space-consuming compression-based handoff-location predictors. Although our handoff-time predictor had modest prediction accuracy, in the context of mobile voice applications we found that bandwidth reservation strategies can benefit from the combined location and time handoff predictor, significantly reducing the call-drop rate without significantly increasing the call-block rate. We also developed a prediction-based routing protocol for mobile opportunistic networks. We evaluated and compared our protocol\u27s performance to five existing routing protocols, using simulations driven by real mobility traces. We found that the basic routing protocols are not practical for large-scale opportunistic networks. Prediction-based routing protocols trade off the message delivery ratio against resource usage and performed well and comparable to each other

Intelligent adaptive bandwidth provisioning for quality of service in umts core networks

Master'sMASTER OF ENGINEERIN

Efficient resource allocation and call admission control in high capacity wireless networks

Resource Allocation (RA) and Call Admission Control (CAC) in wireless networks are processes that control the allocation of the limited radio resources to mobile stations (MS) in order to maximize the utilization efficiency of radio resources and guarantee the Quality of Service (QoS) requirements of mobile users. In this dissertation, several distributed, adaptive and efficient RA/CAC schemes are proposed and analyzed, in order to improve the system utilization while maintaining the required QoS. Since the most salient feature of the mobile wireless network is that users are moving, a Mobility Based Channel Reservation (MBCR) scheme is proposed which takes the user mobility into consideration. The MBCR scheme is further developed into PMBBR scheme by using the user location information in the reservation making process. Through traffic composition analysis, the commonly used assumption is challenged in this dissertation, and a New Call Bounding (NCB) scheme, which uses the number of channels that are currently occupied by new calls as a decision variable for the CAC, is proposed. This dissertation also investigates the pricing as another dimension for RA/CAC. It is proven that for a given wireless network there exists a new call arrival rate which can maximize the total utility of users, while maintaining the required QoS. Based on this conclusion, an integrated pricing and CAC scheme is proposed to alleviate the system congestion

Ubiquitous Computing for Remote Cardiac Patient Monitoring: A Survey

New wireless technologies, such as wireless LAN and sensor networks, for telecardiology purposes give new possibilities for monitoring vital parameters with wearable biomedical sensors, and give patients the freedom to be mobile and still be under continuous monitoring and thereby better quality of patient care. This paper will detail the architecture and quality-of-service (QoS) characteristics in integrated wireless telecardiology platforms. It will also discuss the current promising hardware/software platforms for wireless cardiac monitoring. The design methodology and challenges are provided for realistic implementation

EVEREST IST - 2002 - 00185 : D23 : final report

Deliverable públic del projecte europeu EVERESTThis deliverable constitutes the final report of the project IST-2002-001858 EVEREST. After its successful completion, the project presents this document that firstly summarizes the context, goal and the approach objective of the project. Then it presents a concise summary of the major goals and results, as well as highlights the most valuable lessons derived form the project work. A list of deliverables and publications is included in the annex.Postprint (published version

Enabling Millimeter Wave Communication for 5G Cellular Networks: MAC-layer Perspective

Data traffic among mobile devices increases dramatically with emerging high-speed multimedia applications such as uncompressed video streaming. Many new applications beyond personal communications involve tens or even hundreds of billions wireless devices, such as wireless watch, e-health sensors, and wireless glass. The number of wireless devices and the data rates will continue to grow exponentially. Quantitative evidences forecast that total data rate by 2020 will be 1000 times of current 4G data rate. Next generation wireless networks need fundamental changes to satisfy the overwhelming capacity demands. Millimeter wave (mmWave) communication with huge available bandwidth is a very promising solution for next generation wireless networks to overcome the global bandwidth shortage at saturated microwave spectrum. The large available bandwidth can be directly translated into high capacity. mmWave communication has several propagation characteristics including strong pathloss, atmospheric and rain absorption, low diffraction around obstacles and penetration through objects. These propagation characteristics create challenges for next generation wireless networks to support various kinds of emerging applications with different QoS requirements. Our research focuses on how to effectively and efficiently exploit the large available mmWave bandwidth to achieve high capacity demand while overcoming these challenges on QoS provisioning for various kinds of applications. This thesis focuses on MAC protocol design and analysis for mmWave communication to provide required capacity and QoS to support various kinds of applications in next generation wireless networks. Specifically, from the transmitter/receiver perspective, multi-user beamforming based on codebook is conducted to determine best transmission/reception beams to increase network capacity considering the mutual interferences among concurrent links. From the channel perspective, both interfering and non-interfering concurrent links are scheduled to operate simultaneously to exploit spatial reuse and improve network capacity. Link outage problem resulting from the limited diffraction capability and low penetration capability of mmWave band is addressed for quality provisioning by enabling multi-hop transmission to replace the link in outage (for low-mobility scenarios) and buffer design with dynamic bandwidth allocation among all the users in the whole coverage area (for high-mobility scenarios). From the system perspective, system structure, network architecture, and candidate MAC are investigated and novel backoff mechanism for CSMA/CA is proposed to give more transmission opportunity to faraway nodes than nearby nodes in order to achieve better fairness and higher network capacity. In this thesis, we formulate each problem mentioned above as an optimization problem with the proposed algorithms to solve it. Extensive analytical and simulation results are provided to demonstrate the performance of the proposed algorithms in several aspects, such as network capacity, energy efficiency, link connectivity and so on