Quality of service-based service level agreement management framework for hydrocarbon exploration and discovery operation

 The major contributions presented in this thesis are twofold. Firstly, it presents the research towards a unique services-based Hydrocarbon Exploration and Discovery Model that demonstrates the feasibility of using advanced ICT technologies in the reproduction of stages involved in an oil and gas discovery, processing and analysis process. Secondly, the research demonstrated a solution of the problems in providing agreed level of quality of service (QoS) and formalizing of appropriate Service Level Agreements (SLA) within such complex environment where different services within the model can be delivered by a variety of service providers

Quality-of-service routing for web-based multimedia servers

Quality-of-Service is an important issue in multimedia applications; so far most of the research focuses on bandwidth guarantee, few pays attention to the server performance guarantee. In this paper we pay more attention to the server performance guarantee under the prerequisite of guaranteed bandwidth quality. We take advantage of anycast to find the "best" multimedia server among a distributed server group in terms of bandwidth, the request will be submitted to the selected server, moreover, the selected server's neighbours' (all the servers with feasible paths) addresses are delivered to the selected server simultaneously. If the selected server can not guarantee the QoS for the request in terms of server performance, then a proposed QoS-Aware Server Load Deviation (QASLD) mechanism wiII be employed, which will deliver the request to one of its neighbours until there exists a suitable server that can guarantee the server performance for the request. Our experiments show that the proposed QASLD algorithm works well.

An analytical model for optimal spectrum leasing under constraints of quality of service in CRNs

Cognitive radio improves spectrum efficiency and mitigates spectrum scarcity by allowing cognitive users to opportunistically access idle chunks of the spectrum owned by licensed users. In long-term spectrum leasing markets, secondary network operators make a decision about how much spectrum is optimal to fulfill their users' data transmission requirements. We study this optimization problem in multiple channel scenarios. Under the constrains of expected user admission rate and quality of service, we model the secondary network into a dynamic data transportation system. In this system, the spectrum accesses of both primary users and secondary users are in accordance with stochastic processes, respectively. The main metrics of quality of service we are concerned with include user admission rate, average transmission delay and stability of the delay. To quantify the relationship between spectrum provisioning and quality of service, we propose an approximate analytical model. We use the model to estimate the lower and upper bounds of the optimal amount of the spectrum. The distance between the bounds is relatively narrow. In addition, we design a simple algorithm to compute the optimum by using the bounds. We conduct numerical simulations on a slotted multiple channel dynamic spectrum access network model. Simulation results demonstrate the preciseness of the proposed model. Our work sheds light on the design of game and auction based dynamic spectrum sharing mechanisms in cognitive radio networks.

An energy-aware virtual machine scheduling method for service QoS enhancement in clouds over big data

Because of the strong demands of physical resources of big data, it is an effective and efficient way to store and process big data in clouds, as cloud computing allows on-demand resource provisioning. With the increasing requirements for the resources provisioned by cloud platforms, the Quality of Service (QoS) of cloud services for big data management is becoming significantly important. Big data has the character of sparseness, which leads to frequent data accessing and processing, and thereby causes huge amount of energy consumption. Energy cost plays a key role in determining the price of a service and should be treated as a first-class citizen as other QoS metrics, because energy saving services can achieve cheaper service prices and environmentally friendly solutions. However, it is still a challenge to efficiently schedule Virtual Machines (VMs) for service QoS enhancement in an energy-aware manner. In this paper, we propose an energy-aware dynamic VM scheduling method for QoS enhancement in clouds over big data to address the above challenge. Specifically, the method consists of two main VM migration phases where computation tasks are migrated to servers with lower energy consumption or higher performance to reduce service prices and execution time. Extensive experimental evaluation demonstrates the effectiveness and efficiency of our method.

Service level agreements framework for digital libraries quality of service management

No framework that provides practical approach for the assessment of quality of service level offered by digital libraries exists.This thesis aims to address this gap. The thesis develops a service level agreement (SLA) based mechanisms for the digital libraries to measure and assess the quality of service they deliver to their customers. An SLA is a formal contract between the digital content providers and the digital library consumers.

Interoperable and transparent dynamic deployment of web services for service oriented grids

Dynamic deployment of Web services is a term used frequently when describing the selection and deployment of a service to a grid host. Although current grid systems (such as Globus) provide dynamic deployment, the requirements of the service being deployed are not considered. Therefore truly dynamic deployment cannot be achieved as the services deployed are restricted to the grid system used. We present a dynamic deployment mechanism as part of self configuration in a service oriented grid environment. The dynamic deployment mechanism takes the requirements of the service into consideration, including parameters such as the operating system required to execute the service, the required software libraries, any additional required software packages, price and Quality of Service (QoS) parameters.

Quality control of sensor network data

A wireless sensor network (WSN) is a group of sensors that are geographically distributed and interconnected by wireless networks. Sensors gather information about the state of physical world. Then, after processing forward them to the main destination. To be able to provide this service, there are many aspects of communication techniques that need to be explored. Supporting quality of service (QoS) will be of critical importance for pervasive WSNs that serve as the network infrastructure of diverse applications. To illustrate new research and development interests in this field, this paper examines and discusses the requirements, critical challenges, and open research issues on QoS management in WSNs. A brief overview of recent progress is given.

Digital library service quality assessment model

With the introduction of digital library services, the quality of service (QoS) has become paramount importance for evaluating the performance of the digital library service provisioning. Various models and frameworks have been proposed to evaluate digital library QoS. However, the prevalent research concentration in QoS for digital library is on the dimensions of the perspective of users’ perception. In this paper, we address the same research problem from a different dimension which is from the perspective of the digital service providers. To this end, we propose a new model suitable for evaluating the performance of digital library services. We argue that the level of QoS provided by the digital service providers have direct impact on the perception and satisfaction of the digital service end-users.

Quality of occupational health provision: two rating scales and their determinants

Background To develop quality scales for occupational health services (OHSs) and describe and explain variation in quality across the UK university sector.

Methods Analysis of data from a national survey, to which 93 of 117 (79%) UK universities responded, and from the Higher Education Statistics Agency. Two quality scales were generated, one from the 1985 International Labour Organization recommendations on OHSs and one from clinicians’ perceptions (good, adequate, poor) about their OHS. The determinants examined were number of university staff, type of OHS (in-house, contracted, none/other), number of full-time equivalent occupational health doctors and nurses and OHS leadership (doctor, nurse, other).

Results There was wide variation in quality and a correlation (r = 0.65) between scales. In-house service, increasing service size and leadership by a doctor or nurse were determinants of higher quality; size of the university was not statistically significant after taking account of these factors.

Conclusions Some university OHSs may not be structured or operated to promote the highest quality of service. Inspection of individual quality scale items may be informative. These scales may be applicable in other employment sectors.

Hybrid cloud resource provisioning policy in the presence of resource failures

Resource provisiomng is an important and challenging problem in the large-scale distributed systems such as Cloud computing environments. Resource management issues such as Quality of Service (QoS) further exacerbate the resource provisioning problem. Furthermore, with the increasing functionality and complexity of Cloud computing, resource failures are inevitable. Therefore, the question we address in this paper is how to provision resources to applications in the presence of resource failures in a hybrid Cloud computing environment. To this end, we propose three Cloud resource provisioning policies where we utilize workflow applications to drive the system workload. The proposed strategies take into account the workload model and the failure correlations to redirect requests to appropriate Cloud providers. Using real failure traces and workload models, we evaluated the performance and monetary cost of the proposed policies. The results of our experiments show that we can decrease the deadline violation rate of users' requests to as low as 20% with a limited cost on Amazon public Cloud.

Service level agreements for the digital library

Digital libraries offer a massive set of digital services to geographically distributed library patrons. The digital services are commonly sourced from third-party service providers for charge. As externally sourced digital services are becoming prevalence, issues regarding their quality assessment are gaining critical importance. Unfortunately, sourcing digital services from external providers has brought with it stringent quality of service (QoS) demand from the library service users. Currently, there is no way for ensuring QoS between the digital service providers and the library management. In this paper, we propose service level agreements (SLAs) to capture the QoS requirements of the digital service users and the commitments, as well as adherence of the digital service providers.

A novel energy-efficient cross-application-layer platform with QoS-security support

Security provisioning is an essential part in the design of any communication systems, which becomes more critical for wireless systems. Devising a quality of service (QoS) mechanism to coexist security algorithms is a daunting, yet inevitable task. The aim of this novel research article is to present a novel energy efficient, cross-layer-based application-layer wireless system with simultaneous security and QoS supports, which revolves around the practical and low-cost implementation of Suite-B cryptographic algorithms (promulgated by the National Security Agency) and detailed analyses of the associated complexities. The focus of this article is on the novel cross-layer mechanism and its effectiveness to handle QoS-enabled treatment while offering security enhancements.

Service level agreement management framework for utility-oriented computing platforms

With the increasing popularity of utility-oriented computing where the resources are traded as services, efficient management of quality of service (QoS) has become increasingly significant to both service consumers and service providers. In the context of distributed multimedia content adaptation deployment on service-oriented computing, how to ensure the stringent QoS requirements of the content adaptation is a significant and immediate challenge. However, QoS guarantees in the distributed multimedia content adaptation deployment on service-oriented platform context have not been accorded the attention it deserves. In this paper, we address this problem. We formulate the SLA management for distributed multimedia content adaptation deployment on service-oriented computing as an integer programming problem. We propose an SLA management framework that enables the service provider to determine deliverable QoS before settling SLA with potential service consumers to optimize QoS guarantees. We analyzed the performance of the proposed strategy under various conditions in terms of the SLA success rate, rejection rate and impact of the resource data errors on potential violation of the agreed upon SLA. We also compared the proposed SLA management framework with a baseline approach in which the distributed multimedia content adaptation is deployed on a service-oriented platform without SLA consideration. The results of the experiments show that the proposed SLA management framework substantially outperforms the baseline approach confirming that SLA management is a core requirement for the deployment of distributed multimedia content adaptation on service-oriented systems.