The case for predictable media quality in networked multimedia applications

Shared networks are now able to support a wide range of applications, including real-time multimedia This has led the networking community to consider a wider range of network Quality of Service (QoS) guarantees and pricing schemes. To date, the QoS required by networked multimedia applications has been described in terms of technical parameters. We argue that, in order to maximize the realized quality of any network, the QoS requirements of networked multimedia applications should be based on the value that users ascribe to the media quality they receive in the context of a particular task. This argument is supported with results from a set of studies in which users' perceptions of media quality was investigated for a listening task. We found that users' expectancies of quality directly influenced their ratings: low expectancies produce higher ratings for the same level of objective quality - provided that quality is predictable. In conclusion, we outline the implications of our studies for the design of networked multimedia applications and the network services that support them

Not all bits have equal value: Investigating users' network QoS requirements

The number of Internet users is expected to triple between 1998 and 2002([1]) largely because of new applications (such as videoconferencing) and new services (such as e-commerce). This shift in usage imposes higher Quality of Service (QoS) requirements at different levels of granularity. It also means that the traditional Internet way of managing quality (best-effort) has to be replaced by a more service-oriented approach. The aim of this paper is to investigate end-users' cognitive and perceptive QoS requirements. We present empirical results on user QoS preferences and QoS graduations. Guidelines for translating these results into metrics that can be used to guide resource allocation mechanisms are discussed

It Ain't What You Charge, It's the Way That You Do It: a User Perspective of Network QoS and Pricing

Shared networks, such as the Internet, are fast becoming able to support heterogeneous applications and a diverse user community. In this climate, it becomes increasingly likely that some form of pricing mechanism will be necessary in order to manage the Quality of Service (QoS) requirements of different applications. So far, research in this area has focussed on technical mechanisms for implementing QoS and charging. This paper reports a series of studies in which users' perceptions of QoS, and their attitudes to a range of pricing mechanisms, were investigated. We found that users' knowledge and experience of networks, and the real-world Task they perform with applications, determine their evaluation of QoS and attitude to payment. Users' Payment Behavior is governed by their level of Confidence in the performance of salient QoS parameters. User Confidence, in turn, depends on a number of other factors. In conclusion, we argue that charging models that undermine User Confidence are not only undesirable from the users' point of view, but may also lead to user behavior that may have a negative impact on QoS

Of packets and people: A user-centered approach to quality of service

Multimedia communication has gained increasing attention, both from the application side and the network provider side. While resource provisioning for QoS support in packet switched networks has lead to the design and development of sophisticated QoS architectures, notably ATM, IntServ or DiffServ, research has not exactly been user or application-context centered. In the cause of the evolution of QoS architectures, the integrated service network approach has lost momentum, and with it, the notion of QoS guarantees. Differentiation of QoS classes within the DiffServ framework is based on the definition of various per-hop behaviors. What is currently missing is a technique for specification and mapping of application and user QoS preferences onto evolving service profiles. In addition, adaptation of applications (and users) is becoming increasingly important in the face of dominating weak QoS-assurance paradigms, both in wireline and wireless environments. As a prerequisite, this paper investigates cognitive and perceptive conditioning of users and applications in a situated setting. The contribution of this paper is twofold: First, essential empirical results on user QoS preferences and QoS graduations are presented, and second, methodological foundations are laid for investigating user-centered QoS

Well-Being: From Concept to Practice?

‘Well-being’ has become a high-profile and contested issue, for both policy and practice, since its introduction as an integral part of the Care Act (2014). A dynamic and fluid concept, the researchers were interested in how qualified social workers conceptualise concept of well-being. This small-scale qualitative study, arising from a partnership between a university and a local authority within England, explored how social workers, in one adult social work service, conceptualized ‘well-being’ in relation to service users who both did have the mental capacity, and also those who lacked capacity, to make informed decisions in relation to their care and support needs. The researchers adopted an interpretivist, qualitative approach to the research and used thematic analysis of the rich data arising from individual and group discussions. Interesting differences emerged that, we propose, related to the practitioners’ dominant ‘cognitive style’ or over-arching approach to considering how individuals, with and without capacity, defined their own well-being, becoming more risk-averse when considering the well-being (as defined within the Care Act 2014) of an individual who lacked capacity. Whilst local authorities have a duty under the Care Act to promote an individual’s well-being, firmly locating the well-being principle at the heart of adult social work assessments, it is important to remember that this is a concept that is mainly self-defined. However, the ways in which practitioners conceptualise well-being influence both how they approach an assessment, and indeed how they seek to build relationships with the person being assessed. Bringing the different cognitive styles to practitioners’ attention, we believe, provides an opportunity to challenge their own and their colleagues’ biases, whether systemic or individual, and free them to embrace the fluidity of experience and well-being, for all individuals seeking to access services

Defining user perception of distributed multimedia quality

This article presents the results of a study that explored the human side of the multimedia experience. We propose a model that assesses quality variation from three distinct levels: the network, the media and the content levels; and from two views: the technical and the user perspective. By facilitating parameter variation at each of the quality levels and from each of the perspectives, we were able to examine their impact on user quality perception. Results show that a significant reduction in frame rate does not proportionally reduce the user's understanding of the presentation independent of technical parameters, that multimedia content type significantly impacts user information assimilation, user level of enjoyment, and user perception of quality, and that the device display type impacts user information assimilation and user perception of quality. Finally, to ensure the transfer of information, low-level abstraction (network-level) parameters, such as delay and jitter, should be adapted; to maintain the user's level of enjoyment, high-level abstraction quality parameters (content-level), such as the appropriate use of display screens, should be adapted

What Makes a City Liveable? Implications for Next-Generation Infrastructure Services

Abstract: Infrastructure forms the framework within which modern societies operate both at the physical and social level. It includes (amongst others) digital, green and social infrastructures, emergency services and food networks, water, energy, waste and transport. Infrastructure, by its very nature, locks in behaviours. The Liveable Cities research consortium aims to identify and test radical engineering interventions that will lead to future low carbon, resource secure cities in which societal wellbeing is prioritised, and these will necessarily influence the shape of infrastructure provision. This paper presents a discussion of what comprises a liveable city and how it might be achieved. It presents the City Design Framework, a technique for the analysis of city strategies that establishes a hierarchy of needs relevant to successfully achieving a liveable city. The framework supports changing perceptions of infrastructure since the necessary future changes have the potential to radically alter people’s lifestyle and wellbeing. Citation: Leach, J.M., Lee, S.E., Braithwaite, P.A., Bouch, C.J., Grayson, N. & Rogers, C.D.F. (2014). What Makes a City Liveable? Implications for Next-Generation Infrastructure Services. In: Campbell P. and Perez P. (Eds), Proceedings of the International Symposium of Next Generation Infrastructure, 1-4 October 2013, SMART Infrastructure Facility, University of Wollongong, Australia

Using XML and XSLT for flexible elicitation of mental-health risk knowledge

Current tools for assessing risks associated with mental-health problems require assessors to make high-level judgements based on clinical experience. This paper describes how new technologies can enhance qualitative research methods to identify lower-level cues underlying these judgements, which can be collected by people without a specialist mental-health background. Methods and evolving results: Content analysis of interviews with 46 multidisciplinary mental-health experts exposed the cues and their interrelationships, which were represented by a mind map using software that stores maps as XML. All 46 mind maps were integrated into a single XML knowledge structure and analysed by a Lisp program to generate quantitative information about the numbers of experts associated with each part of it. The knowledge was refined by the experts, using software developed in Flash to record their collective views within the XML itself. These views specified how the XML should be transformed by XSLT, a technology for rendering XML, which resulted in a validated hierarchical knowledge structure associating patient cues with risks. Conclusions: Changing knowledge elicitation requirements were accommodated by flexible transformations of XML data using XSLT, which also facilitated generation of multiple data-gathering tools suiting different assessment circumstances and levels of mental-health knowledge