Quality of service management for multimedia communications : investigations on usability of interfaces for desktop and portable systems

Multimedia communication is now possible via the use of high bandwidth channels, and communication protocols that support Quality of Service (QoS) requests. However, these technologies often fall short of user expectations by not providing effective user interfaces that can facilitate negotiations between the user and the system. In this thesis, a set of conceptual models are developed to create a user-centred QoS management system for networked multimedia applications. Various interfaces are designed and developed for ‘specifying’ and ‘negotiating’ QoS prior to initiating a multimedia session, and ‘re-negotiating’ QoS in real-time during the multimedia session. The interfaces developed in this research provide the means for managing QoS for fixed as well as mobile multimedia communications. Usability investigations were conducted to evaluate the efficacy of these interfaces for specifying, negotiating and re-negotiating QoS on Desktop Systems and on Portable Devices – such as, Personal Digital Assistants (PDAs) and Mobile Phones. Conducting the usability tests for these interfaces required re-engineering of traditional usability testing processes – to improve the efficiency of performing each test and collecting data. Ten separate usability studies were performed using Beginner, Intermediate, and Advanced users to investigate novel Human Computer Interaction (HCI) methods for: computer control and system feedback; QoS specification and negotiation on Desktop Computers; and QoS re-negotiation on Desktop Systems and Portable Devices. Users agreed that there is a need for such interfaces that enable them to request, negotiate and re-negotiate QoS. Usability studies for these interfaces show good usability and learnability for technical as well as non-technical users. The innovative interaction methods developed in this research project, by far, enhanced the user’s experience in managing QoS, however, suggestions for further improvements were also given by the participants.

Name dc:type.qualificationname

phd

Level dc:type.qualificationlevel

doctoral

Grantor dc:publisher.institution

Victoria University

Year dc:date.issued

2007

Author dc:creator

• Georgievski, Mladen

• School of Engineering and Science
• 1005 Communications Technologies

Language dc:language

en