An IMS Architecture and Algorithm Proposal with QoS Parameters for Flexible Convergent Services with Dynamic Requirements

Quality of Service (QoS) provisioning is one of the main requirements in the 3GPP IP Multimedia Subsystem (IMS) and it has been addressed in different works since the beginning of the IMS standardization process. As a result of the fixed and mobile networks evolution, the parameters standardized in IMS have changed constantly until the specification of the Policy and Charging Control (PCC) architecture that integrates IMS QoS and charging functionalities. However, current IMS QoS specifications still have some limitations to handle service flexibility that is required to provide Internet services over IMS. In this work, we propose an enhanced IMS QoS architecture to support efficient QoS providing for flexible services with dynamic requirements. This proposal is compared against different approaches to evaluate their behavior under network saturation conditions. Simulations results show that the architecture we propose achieves efficiency and flexibility, maintaining the number of blocked and active sessions, and increasing the number of high priority sessions activated in a saturated network

The design of accessible, usable and meaningful content. Volume 1: Explanatory Essay

This Explanatory Essay discusses the 31 papers which I have authored, or made a substantial contribution to, and submitted for a PhD by Prior Publication. The Essay presents these publications in the light of their original contribution to an emerging theme of concern, Content Design, which I will argue is the deliberate design of content so that it is accessible, usable and meaningful. Content is any type of information carrying material that is produced in any medium or mixture of media, for human, as opposed to machine, consumption. As such, content has always played an important role in our lives. In the Information Age, however, the importance of this role is becoming critical. This may be attributed to many factors, including: the inexorable proliferation of digitally produced content of all types; the increased possibilities, even expectations, to interact with content; and our growing reliance upon information. Thus, there should be a renewed attention to design of content, particularly its accessibility, usability and meaningfulness. There are many research areas that deal with aspects of content. I believe that deliberate attention to the composition and structuring of content can benefit from all of these. Content Design represents a multifaceted 'problem space' that draws on a wide variety of disciplines, from the humanities to the sciences. It also has lessons to learn from traditional ways of meaning-making, particularly literary studies and rhetoric. This problem space is a place to pull together knowledge and expertise that is needed in the digital age to help to design content so that it is consumable by humans. In this Essay, my publications are situated within three strands of research that offer such knowledge and expertise: Discourse Studies; the Uses of Metadata; and the Accessibility of Content. Broadly speaking, my work contributes, within these strands, to the design of content in terms of composing, packaging and making content apprehendable