Quality Of Service Concept Research Articles

Evaluation of the QoS policy model of an ordinary 5G smart city cluster with predominant URLLC and eMBB traffic

A typical element of the smart city’s information and communication space is a 5G cluster, which is focused on serving both new and handover requests because it is an open system. In an ordinary 5G smart city cluster, Ultra-Reliable Low-Latency Communications (URLLC) and enhanced Mobile BroadBand (eMBB) traffic types prevail. The formation of an effective QoS policy for such an object (taking into account the potentially active slicing technology) is an urgent problem. As a baseline, this research considers a Quality of Service (QoS) policy with constraints for context-defined URLLC and eMBB classes of incoming requests. Evaluating the QoS policy instance defined within the framework of the basic concept requires the formalization of both a complete qualitative metric and a computationally efficient mathematical apparatus for its calculation. The article presents accurate and approximate methods of calculating such quality parameters as the probability of loss of typed requests and the utilization ratio of the communication resource, which depend on the implementation of the estimated QoS policy. At the same time, the original parametric space includes both fixed characteristics (amount of available communication resources, load according to request classes) and controlled characteristics due to the specifics of the implementation of the basic QoS concept. The paper empirically proves the adequacy of the presented mathematical apparatus for evaluating the QoS policy defined within the scope of the research. Also, in the proposed qualitative metric, a comparison of the author’s concept with a parametrically close analogue (the well-known QoS policy scheme, which takes into account the phenomenon of reservation of communication resources), determined taking into account the reservation of communication resources, was made. The results of the comparison testify in favour of the superiority of the author’s approach in the proposed metrics.

Driver’s Perceived Satisfaction at Urban Roundabouts—A Structural Equation-Modeling Approach

In recent years, the use of roundabouts in road networks has reflected a sustainable and modern solution for traffic intersections. Their implementation, integrated design, and proper evaluation are a necessity to achieve their beneficial results. According to the latest edition of the Highway Capacity Manual (HCM) and the Highway Capacity and Quality Service (HCQS), a comprehensive evaluation of a roundabout is based on the interchangeable use of the LOS (level of service) and QOS (quality of service). Both manuals describe the LOS criteria, which are the same as those currently used for unsignalized at-grade intersections, while the QOS methodological description and criteria are not specifically defined. The quality of service, which corresponds to road users’ perceived satisfaction, is determined by identifying and evaluating certain factors that have an impact on users. While the previous work on evaluating the quality of roundabouts is limited, this work aimed to present and evaluate the concept of QOS for urban roundabouts in Greece and to assess the factors that affect drivers’ perceived feeling of comfort. The methodology used for the research, included data collection via an on-line questionnaire addressed to the users of the Greek road network and a statistical analysis based on the performance of six latent variables named quality components (exploratory factor analysis). A structural equation model (SEM) was used to determine the causal relationship between primary factors and quality components. It was noted that the SEM cannot predict the travel behavior but it has ability to express relationships between unobserved and observed variables. The results of the revealed model are of great value for the development of: (a) a comprehensive conceptual framework of the QOS and (b) a critical analysis of the parameters that should be considered for the assessment of the QOS of a roundabout. Identifying the factors that influence road users’ perception in terms of safety and comfort (quality of service) leads to a better knowledge and understanding of the road network characteristics that are important to road users and that influence their behavior and level of satisfaction.

A Secure Optimization Algorithm for Quality-of-Service Improvement in Hybrid Wireless Networks

Various industrial, scientific and commercial processes involve wireless mesh networks in the recent days. These technologies improve communication technology to a large extent which has led to an increase in utilization of these systems in various fields. In application with intense and complex data flow, improving the quality of service (QoS) has been a challenge and a focus of research leading to more advanced wireless communication systems. This paper provides a novel optimization algorithm for improving the QoS in hybrid wireless networks while preventing malware and routing attacks. The concept of QoS and hybrid wireless networks are examined at the initial stage. Further, the algorithm for optimizing the service quality in the network is proposed accordingly. The ability of data transfer is benefited by data packets in this algorithm. Load distribution is performed such that overcrowding is prevented and information routing is done efficiently though the nodes. Delay or routing is created and control messages are sent for withholding data when certain nodes are overcrowded. This reduces the delay created by overcrowding by 50% while maintaining the permittivity.

A mathematical model and NSGA-II algorithm for bi-objective grid scheduling problem with quality of service satisfaction

Computational grids consist of the innovative technologies of the new era, which seek to accelerate performance through distributing tasks on computing resources. A grid system makes it feasible to run great computing operations through the connected processors. In this article, a bi-objective problem of grid scheduling based on quality of service concept is discussed. The first objective is to increase the profit earned from customers and the second, to increase the utilisation of computational resources. A mathematical programming model is proposed for the problem and a meta-heuristic NSGA-II algorithm is designed and customised for the problem. In the numerical analysis, by drawing Pareto diagrams and analysing the sensitivity thereof, the efficiency of the proposed methods and the effect of different parameters of the problem on both the methods are assessed. According to the results, the proposed NSGA-II algorithm is highly efficient in terms of solution quality and run time.

Envelope modeling of renewable resource variability and capacity

To unify the analysis of both renewable and conventional fossil-fuel generating resources in electricity systems, we develop an envelope-based modeling method. Built on Network Calculus theory (NetCal) for deterministic queuing systems from the field of telecommunications engineering, this method characterizes the variability of electricity supply and demand by upper and lower envelopes and their respective Legendre conjugates. Differing from all other modeling methods, this method not only quantifies variability across different time scales, but also captures the intrinsic tradeoff between capacity and the corresponding Quality-of-Service (QoS) performance. In particular, the QoS measures represent matching/mismatching patterns between power supply and demand and provide an intuitive interpretation of the role of storage resources. The concept of QoS leads to two QoS-based capacity metrics – guaranteed capacity and best-effort capacity – whose conceptual and numerical properties are analyzed and compared against existing capacity metrics for validation purpose. As illustration, the proposed methods are applied to data from the California Independent System Operator (CAISO), which allows us to explicitly quantify the capacity contribution (via the notion of best-effort capacity) of wind during peak hours and its negative system impact at night, and demonstrates the positive capacity contribution of storage resources even though they are net energy consumer.

Towards an ideal service QoS in fuzzy logic-based adaptation planning middleware

Mobile applications require an adaptation phase to adapt to the user's and application context. Utility functions or rules are most often used to make the adaptation planning or decision, i.e. select the most adapted variant for each required service. Fuzzy controllers are used when it is difficult or even impossible to construct precise mathematical models. In the case of mobile applications, the large number of Quality of Service (QoS) and context parameters causes an exponential increase in the number of rules (aka. rule explosion problem), that increases the processing time of the adaptation planning. To reduce the processing time and simplify the fuzzy control system, we propose the concept of ideal QoS. Fuzzy values of ideal QoS parameters are calculated using several fuzzy control systems to fit the context state and user preferences. A fuzzy logic similarity metric based on fuzzy sets and fuzzy operators is proposed to select the service variant having the nearest QoS values to the ideal. Experiments show that our approach can significantly improve both the number of rules and the processing time when selecting the variant that well adapts to environment changes.

Quality of service in manufacturing networks: a service framework and its implementation

Due to the continuous growth in the application of networks in manufacturing, quality of service (QoS) has become an important issue. In this paper, the concept of QoS for manufacturing networks is discussed. To provide overall performance assurance for manufacturing networks, a service framework integrating the QoS mechanisms of the networked resource service management function and the communication networks is proposed. The novel framework maps an application to resource services and then to communication networks, adopts an intelligent optimisation algorithm for QoS management of resource services, and provides QoS schemes for data transfer across communication networks. A prototype implementation has been realised and a set of simulation experiments conducted to evaluate the validity of the framework. The results obtained demonstrate the ability of the framework to satisfy the various performance requirements posed by such applications and provide efficient overall performance assurance for manufacturing networks.

A Method for Semantic Web Service Selection Based on QoS Ontology

In order to select the proper one from the web service candidate sets which are provided by semantic matching, a method for web service selection with QoS (quality of service) constraints is proposed. In this paper, firstly, the Four-Level Matching Model for Semantic Web Service based on QoS Ontology, which includes Application Domain Matching, Description Matching of Service, Function Matching of Service and QoS Matching, is presented, then, the QoS ontology for web service is constructed and the QoS description information with the QoS concept in OWL-S (Web Ontology Language for Services) model is extended, thirdly, the extensible OWL-SQ model for service description with service semantic and QoS description is presented, and it is QoS supporting and constraining. Then based on decision theory and normalized algorithm, the dimensionless method of QoS properties for un-numerical value type and numerical value type in OWL-SQ model is proposed. Finally, the algorithm for constructing matching matrix of QoS and the service selection method are presented, to evaluate and select optimization candidate web service comprehensively. Test result shows that the efficiency and accuracy of service selection are improved with the service selection method based on OWL-SQ model.

A Novel Embedded Statistical Scheduler for Realising High System-QoS

A Novel Embedded Statistical Scheduler for Realising High System-QoS

Session‐based end‐to‐end policy control in 3GPP evolved packet system

AbstractThe Third Generation Partnership Project specifies a solution to handle the heterogeneity of future networks, including quality of service (QoS) and charging aspects. This solution utilizes a policy‐based approach based on the policy and charging control (PCC) architecture, which is an integral component of the evolved packet system (EPS). The specifications for EPS are being finalized with the evolved packet core (EPC) central to this framework. The EPC is a simplified, flat, all IP‐based architecture that supports mobility between heterogeneous access networks and incorporates an evolved QoS concept based on the PCC framework. A critical open issue within EPS is the provisioning of end‐to‐end QoS enabled paths. This article proposes enhancements to the EPC/PCC framework that extend the end‐to‐end inter‐domain mechanisms to discover the signaling routes at the service control layer, and use this information to determine the paths traversed by the media at the resource control layer. Because the approach operates at these layers, it is compatible with existing transport networks and exploits already existing QoS control mechanisms. A real testbed implementation, comprising free and open source software, is used to evaluate the proposed mechanisms. The obtained results show that the framework has an acceptable effect on session setup delay and core traffic overhead in a range of scenario ranging from simple, to typical, to worst case. Copyright © 2010 John Wiley & Sons, Ltd.

Composite quality of service and decision making perspectives in wireless networks

Supporting quality of service (QoS) in wireless networks has been a very rich and interesting area of research. Many significant advances have been made in supporting QoS in single wireless networks. However, the support for the QoS across multiple heterogeneous wireless networks will be required in the future wireless networks. In connections spanning multiple wireless networks, the end-to-end QoS will depend on several factors such as mobility and connection patterns of users, and the QoS policies in each of the wireless networks. The end-to-end QoS is also affected by multiple decisions that must be made by several different network entities for resource allocation. The paper has two objectives: one is to demonstrate the decision making process for resource allocation in multiple heterogeneous wireless networks and the second is to present a novel concept of composite QoS in such wireless environment. More specifically, we present an architecture for multiple heterogeneous wireless networks, decision making process for resource request and allocation, a simulation model to study composite QoS, and several interesting results. We also present potential implications of composite QoS on users and network service providers. We also show how the QoS ideas presented in this paper can be used by wireless carriers for improved QoS support and management. The paper can form the basis for a significant further research in DSS for emerging 3G/4G wireless networks supporting QoS for a range of sophisticated and resource intensive mobile applications.

User-perceived quality of service in wireless data networks

For so long, the term quality of service (QoS) has been a pursuit area for network engineers trying to dimension wireless networks to run in the most efficient way possible. Of late, there has been a trend reversal, looking at the user perceptions of the network performance to decide where dimensioning can have the greatest impact. This paper demonstrates the importance of defining the concept of user-perceived QoS and linking this to specific wireless data network parameters for some anticipated valuable applications. It has been shown that a quantitative rating can be obtained for a variety of important factors in the assessment of service quality, and mapped to specific values of multiple network parameters. We found QoS to be application-specific, where various applications require different levels of network performance to satisfy users. The role of physical location was also examined, investigating the influence of being indoors versus outdoors on the user perception of QoS.

QoS-based media retrieval for networked digital archives

When digital multimedia data are retrieved from distributed digital archives, Quality of Service (QoS) criteria can be used to enhance the user's usability. In this paper, assuming best-effort networks as the infrastructure, we describe a multimedia (MM) retrieval method based on the QoS concept for MM data archives in heterogeneous communication environments. We introduce a multi-level QoS model and use response time, which is calculated based on a system-level QoS criterion, as an application-level QoS criterion. The order of retrieving MM data is determined, based on both key-word matching using key words specified by the user and the application-level QoS criterion. A prototype system is developed for retrieving sightseeing-related MM data including video, images, voice, and text. The proposed method of data retrieval has a shorter response time than methods that do not take QoS criteria into account. Also, a search method based on key-word association is described that enables wide-area search and effective information finding.

Network Quality of Service for the Enterprise: A Broad Overview

One of the biggest challenges facing the Internet today is to scale to an infrastructure that can provide quality-of-service (QoS) to a wide variety of applications and traffic types. As the Internet continues to grow at a rapid pace and new applications emerge, the task of managing bandwidth becomes more important. This implies that the traditional “best-effort” service that is provided by TCP/IP is no longer sufficient in many cases. The concept of QoS has evolved to meet the increasing need for bandwidth management. This paper provides an overview of what QoS is why we need it, and what the current approaches for implementing it are. The paper also compares some existing vendor products in the QoS space and finally provides insights into some of the vexing problems that still remain difficult to solve for QoS designers.

Dynamic bandwidth management and adaptive applications for a variable bandwidth wireless environment

This article describes an approach for providing dynamic quality of service (QoS) support in a variable bandwidth network, which may include wireless links and mobile nodes. The dynamic QoS approach centers on the notion of providing QoS support at some point within a range requested by applications. To utilize dynamic QoS, applications must be capable of adapting to the level of QoS provided by the network, which may vary during the course of a connection. To demonstrate and evaluate the dynamic QoS concept, we have implemented a new protocol called dynamic resource reservation protocol (dRSVP) and a new QoS application program interface (API). The paper describes this new protocol and API and also discusses our experience with adaptive streaming video and audio applications that work with the new protocol in a testbed network, including wireless local area network connectivity and wireless link connectivity emulated over the wired Ethernet. Qualitative and quantitative assessments of the dynamic RSVP protocol are provided.

Logistical quality of service in NetSolve

From its inception a principal goal of the Next Generation Internet (NGI) has been to find a way to provide reliable, scalable, cost effective, and deployable delivery of data with quality of service (QoS) guarantees as a foundation for innovative NGI applications. But while schemes to provide reliable end-to-end QoS are being actively pursued on a number of fronts, the well known problems with the scalability, cost, and deployability of end-to-end QoS continue to obstruct progress toward achieving this end. Our research focuses on the nature and potential value of an approach to providing QoS that builds on a strategy for allowing NGI applications to dynamically manage remote storage resources in order to stage data locally for later delivery. We call this strategy logistical Quality of Service ( logistical QoS). The concept of logistical QoS is a generalization of the typical end-to-end model for reserving QoS, permitting much more flexible use of buffering of messages in order to achieve QoS delivery without difficult end-to-end requirements. Whenever data is available to be sent well before it needs to be received, it can be staged, i.e. moved in advance to a location close to the receiver for later delivery. Isolating the act of buffering data as a distinct operation, independent of delivery to the receiver, opens up a new dimension of freedom in the management of communication and storage resources that can offer NGI application developers a wide variety of new opportunities to innovate. Our project focuses on the development of logistical QoS as enabling network functionality for application-driven staging and scheduling of distributed computation on NGI. It is divided into two parts: (1) research on the basic network functionality that is required to support logistical QoS that is reliable, scalable, cost effective, and easy to use; and (2) research that investigates the integration of logistical QoS and the basic network technology that underlies it with the scheduling of distributed computations using NetSolve and the Network Weather Service. Our work on logistical QoS focuses on the Internet Backplane, as providing a mechanism for managing remote storage resources, and the Internet Backplane Protocol, as enabling technology for using that mechanism. The idea underlying the concept of the Internet Backplane is that NGI will enable us to consider the global network as an extension of the processor backplane, if only we have a low overhead mechanism for fine grained naming and access to data, analogous to physical addresses and bus transfers. By this analogy the Internet Backplane is a common namespace for fine-grained management of distributed resources. The IBP provides a flexible interface to enable this functionality, allowing reliable and flexible control of remote storage buffers through a general scheme for naming, staging, delivering and protecting data. We will test logistical QoS as an enabling technology for NGI computing using NetSolve. NetSolve is a software environment for networked computing designed to transform disparate computers and software components into a unified, easy-to-access computational service; it is being used by NSF's Partnerships for Advanced Computational Infrastructure to build high-performance systems for distributed computation on leading edge networks. We will investigate the implementation of logistical QoS within NetSolve and the integration of IBP with the Network Weather Service (used to monitor and forecast the performance of network and computational resources) to build a scheduling capability that maximizes the performance of NetSolve across next generation networks.

A survey of quality of service in mobile computing environments

The specification and management of quality of service (QoS) is important in networks and distributed computing systems, particularly to support multimedia applications. The advent of portable laptop computers, palmtops, and personal digital assistants with integrated communication capabilities facilitates mobile computing. This article is a survey of QoS concepts and techniques for mobile distributed computing environments. The requirements of current and future mobile computing are examined and the services required to support mobility are discussed. Generic concepts of QoS specification and management are overviewed followed by an analysis of the QoS work specific to mobile computing environments.

Quality of service in telecommunications. I. Proposition of a QoS framework and its application to B-ISDN

The the quality of service (QoS) concept is becoming an ever more important issue in telecommunication and computer communication. The article focuses on the QoS notion and concept. The definition of QoS in the International Telecommunications Union-Telecommunications Sector (ITU-T) recommendations and the International Standards Organization (ISO) standards is analysed. Little is known about the asynchronous transfer mode (ATM) performance requirements of the broadband integrated services digital network (B-ISDN) services, especially for multimedia applications. This is because the ATM performance requirements of multimedia applications depend not only on the diverse QoS requirements from application and user, but also on the protocol stacks and scheduling in end systems. Therefore, in order to guarantee QoS to the user, it is necessary to introduce a set of QoS parameters whose properties indicate the nature and requirements of the layered protocol stack. We describe how a proposed QoS framework can be applied to B-ISDN as a specific network. The QoS aspects related to B-ISDN signaling (the control plane) and the QoS aspects related to layer and plane management (the management plane) are described. We also describe how the QoS framework resides in a protocol stack and works together with the B-ISDN network management and signaling.