Traditional Quality Of Service Research Articles

Part 4: Capacity and Quality of Service: Service Reliability and Hidden Waiting Time: Insights from Automatic Vehicle Location Data

Traditional transit service quality measures separate waiting time from service reliability and thereby underestimate the real cost of waiting and fail to evaluate the effect of unreliability on passengers. This study's analysis of passenger behavior shows that, for short headway service, the cost of waiting involves not only the mean time spent waiting on the platform but also potential waiting time, that is, the additional time that passengers have to budget for waiting. Budgeted waiting time is based on an extreme of the waiting time distribution such as its 95th percentile value, which is extremely sensitive to service reliability. Methods for determining the distribution of passenger waiting time from automatic vehicle location (AVL) data are derived. For long headway service, actual and budgeted waiting times are shown to be related to high and low extremes of the schedule deviation distribution, which can likewise be determined from AVL data. Two other components of long headway waiting, schedule i...

Service Reliability and Hidden Waiting Time

Traditional transit service quality measures separate waiting time from service reliability and thereby underestimate the real cost of waiting and fail to evaluate the effect of unreliability on passengers. This study's analysis of passenger behavior shows that, for short headway service, the cost of waiting involves not only the mean time spent waiting on the platform but also potential waiting time, that is, the additional time that passengers have to budget for waiting. Budgeted waiting time is based on an extreme of the waiting time distribution such as its 95th percentile value, which is extremely sensitive to service reliability. Methods for determining the distribution of passenger waiting time from automatic vehicle location (AVL) data are derived. For long headway service, actual and budgeted waiting times are shown to be related to high and low extremes of the schedule deviation distribution, which can likewise be determined from AVL data. Two other components of long headway waiting, schedule inconvenience and synchronization cost, are also analyzed. Waiting cost functions and waiting time measures that account for both headway and service reliability are developed and are harmonized in a framework that provides a smooth transition from short to long headway waiting. Examples show how service reliability can be measured as a waiting cost and how service reliability improvements can reduce waiting cost as much as a large reduction in headway can.

Localised credit based QoS routing

Localised quality of service (QoS) routing has recently been proposed as a viable alternative approach to traditional QoS routing algorithms that use global state information. In this approach, problems associated with maintaining global state information are avoided by having the source nodes to infer the network QoS state based on flow blocking statistics collected locally, and perform flow routing using this localised view of the network QoS state. A credit based routing algorithm (CBR) which is a simple yet effective localised QoS routing algorithm is introduced. Its performance is compared against the localised proportional sticky routing (PSR) algorithm using different types of network topologies, QoS requirements and traffic patterns and under a wide range of traffic loads. Extensive simulations show that the algorithm outperforms the PSR scheme while maintaining the same level of adaptivity and stability. Its performance is also compared against the global widest-shortest path algorithm (WSP) and it is shown that CBR gives a comparable performance with better time complexity and very low communication overhead.

The added value of web innovation for customer satisfaction

PurposeRecent studies have explored the effects of e‐service quality on satisfaction and loyalty of online customers by extending and supplementing traditional service quality frameworks. This research proposes a combination of traditional service quality and e‐service quality frameworks. The central question focuses on how to assess the added value of the web as a service innovation for a traditional service. The setting of the study is a traditional‐style barbeque delivery service with a recently installed advanced web‐initiated order entry facility now used by a majority of the customers.Design/methodology/approachAn empirical, survey‐based cross‐sectional study on web‐initiated customer experiences of an in‐home catering service, involving barbeque food items and cooking equipment.FindingsFindings indicate that adding an innovative e‐channel to a traditional business process does not automatically translate to a higher customer satisfaction. Only limited significant effects were found from online ordering on overall satisfaction in contrast to the effect of traditional service dimensions.Research limitations/implicationsFurther research is needed on the joint analysis of e‐services and traditional services.Practical implicationsE‐service dimensions appear to have a limited impact on overall satisfaction in a traditional business context.Originality/valueThis is one of the first empirical studies combining both traditional and e‐service dimensions and relating them to customer satisfaction.

Quality of perception: user quality of service in multimedia presentations

We define quality of perception (QoP) as representing the user side of the more technical and traditional quality of service. QoP encompasses not only a user's satisfaction with the quality of multimedia presentations, but also his/her ability to analyze, synthesise and assimilate the informational content of multimedia displays. We found that significant reductions in frame rate and color depth does not result in a significant QoP degradation.

Supporting User Needs in a Network: A New Queue Management Technique

Traditional network-level Quality of Service (QoS) techniques are efficient from a network perspective, but they have not provided end-to-end QoS that is satisfactory to users. In this letter, a Coordinated Packet Discard scheme for the distribution of end-to-end QoS requirements into local loss constraints, as well as provision of local loss assurance is proposed. Experiments demonstrate its advantages on increasing QoS-satisfied user ratio and improving network efficiency.

Customer Satisfaction in Virtual Environments: A Study of Online Investing

Many firms are moving to make virtual interfaces their primary, or even sole, points of customer contact. In this environment, some traditional service quality dimensions that determine customer satisfaction, such as the physical appearance of facilities, employees, and equipment, and employees' responsiveness and empathy are unobservable. In contrast, trust may play a central role here in enhancing customer satisfaction. We model trust as an endogenously formed entity that ultimately impacts customer satisfaction, and we elucidate the linkages between trust and other factors related to the performance of the online service provider and to the service environment. The model is validated using two samples—one comprising 225 online investors of a large online broker, and the other comprising 203 members of the American Association of Individual Investors (AAII). The findings suggest that perceived trustworthiness of an online broker is a significant antecedent to investors' satisfaction, and that perceived environmental security and perceived operational competence impact the formation of trust. The results have important managerial implications.

Defining the customer’s expectations in e‐business

E‐commerce has recently generated, at a very fast rate, a lot of new techniques trying to win customers and make money. The success of these techniques can only be real if the customer recognizes them and, most important of all, starts buying from you. This paper deals with discovering an e‐commerce user’s expectations that make them qualify and choose an e‐business supplier. To accomplish this, we use the “critical incident technique”. This method results in a hierarchical relationship between critical incidents, satisfaction items and customer’s needs, that are related to quality dimensions. The quality dimensions obtained changed in relation to the traditional service quality dimensions, showing that after a period of experience, the customer starts to establish his/her quality standards and take decisions based on these standards. Both the surviving and the successful companies are those which will learn to identify, understand and satisfy these needs.

Providing deterministic packet delays and packet losses in multimedia wireless networks

Abstract‘Anytime, anywhere’ communication, information access and processing are much cherished in modern societies because of their ability to bring flexibility, freedom and increased efficiency to individuals and organizations. Wireless communications, by providing ubiquitous and tetherless network connectivity to mobile users, are therefore bound to play a major role in the advancement of our society. Although initial proposals and implementations of wireless communications are generally focused on near‐term voice and electronic messaging applications, it is recognized that future wireless communications will have to evolve towards supporting a wider range of applications, including voice, video, data, images and connections to wired networks. This implies that future wireless networks must provide quality‐of‐service (QoS) guarantees to various multimedia applications in a wireless environment.Typical traffic in multimedia applications can be classified as either Constant‐Bit‐Rate (CBR) traffic or Variable‐Bit‐Rate (VBR) traffic. In particular, scheduling the transmission of VBR multimedia traffic streams in a wireless environment is very challenging and is still an open problem. In general, there are two ways to guarantee the QoS of VBR multimedia streams, either deterministically or statistically. In particular, most connection admission control (CAC) algorithms and medium access control (MAC) protocols that have been proposed for multimedia wireless networks only provide statistical, or soft, QoS guarantees.In this paper, we consider deterministic QoS guarantees in multimedia wireless networks. We propose a method for constructing a packet‐dropping mechanism that is based on a mathematical framework that determines how many packets can be dropped while the required QoS can still be preserved. This is achieved by employing: (1) An accurate traffic characterization of the VBR multimedia traffic streams; (2) A traffic regulator that can provide bounded packet loss and (3) A traffic scheduler that can provide bounded packet delay. The combination of traffic characterization, regulation and scheduling can provide bounded loss and delay deterministically. This is a distinction from traditional deterministic QoS schemes in which a 0% packet loss are always assumed with deterministically bounding the delay.We performed a set of performance evaluation experiments. The results will demonstrate that our proposed QoS guarantee schemes can significantly support more connections than a system, which does not allow any loss, at the same required QoS. Moreover, from our evaluation experiments, we found that the proposed algorithms are able to out‐perform scheduling algorithms adopted in state‐of‐the‐art wireless MAC protocols, for example Mobile Access Scheme Based on Contention and Reservation for ATM (MASCARA) when the worst‐case traffic is being considered. Copyright © 2002 John Wiley & Sons, Ltd.

What It Was Like, What Happened, and What It's Like Now: Developments in Telecommunications Over Recent Decades

A survey of telecommunications over past decades. Overall prices of services have declined less rapidly since deregulation, with local rates rising, long-distance rates falling. Productivity increased strongly during period of Bell System regulated monopoly. Service quality of traditional telephone services has fallen, but many new services have been added. Innovations in customer premise equipment since deregulation far exceed those in prior years. Many major network innovations occurred during years of Bell System monopoly and network innovations have continued since. Actions by the Federal Communications Commission actions anteceded government antitrust case and are responsible for most of the changes since 1978. Most of the beneficial changes have little, if anything, to do with antitrust case and divestiture.

Engineering end-to-end IP resilience using resilience-differentiated QoS

Network resilience is becoming a key issue in the design of IP-based multimedia and multiservice networks. The current discussion about IP network resilience centers around MPLS-based recovery mechanisms. Any well designed recovery strategy has to take into account the different resilience requirements of the single traffic flows in order to avoid excessive usage of bandwidth for standby links. Faced with multiple recovery options, an ISP or NSP must decide which flows to protect to what extent against network failures. In this article an extension to existing quality of service (QoS) architectures is presented that integrates the signaling of resilience requirements with the traditional QoS signaling. We refer to this extended QoS model as resilience-differentiated QoS (RD-QoS). At the border of MPLS domains, the resilience requirements can then be directly mapped to the appropriate MPLS recovery options. A traffic engineering process for the provisioning of the resilience classes is introduced, and a case study demonstrates the significant network capacity savings achievable via this approach.

Hospitality service quality and the role of performance appraisal

This paper overviews the human resources processes and their relationships with service quality (SQ) and total quality management (TQM) in a hotel setting. More importantly, this research presents a new model for the hospitality SQ measurement that incorporates hotel employees’ performance into the SQ level measurement. This new SQ for customer satisfaction model, in turn, can be integrated directly into the hospitality TQM operation since SQ is a basic component of TQM. This new model prevails over the traditional SQ models on several areas. First, the new model is more comprehensive. Also, the new model reflects the actual SQ situation better. Moreover, the new model fits the TQM concept better as both TQM and staff performance aim at continuous improvement in which the former steers towards continuous improvement of each process whereas the latter directs towards continuous improvement in performance.