A unified data repository for rich communication services

Rich Communication Services (RCS) is a framework that defines a set of IP-based services for the delivery of multimedia communications to mobile network subscribers. The framework unifies a set of pre-existing communication services under a single name, and permits network operators to re-use investments in existing network infrastructure, especially the IP Multimedia Subsystem (IMS), which is a core part of a mobile network and also acts as a docking station for RCS services. RCS generates and utilises disparate subscriber data sets during execution, however, it lacks a harmonised repository for the management of such data sets, thus making it difficult to obtain a unified view of heterogeneous subscriber data. This thesis proposes the creation of a unified data repository for RCS which is based on the User Data Convergence (UDC) standard. The standard was proposed by the 3rd Generation Partnership Project (3GPP), a major telecommunications standardisation group. UDC provides an approach for consolidating subscriber data into a single logical repository without adversely affecting existing network infrastructure, such as the IMS. Thus, this thesis details the design and development of a prototypical implementation of a unified repository, named Converged Subscriber Data Repository (CSDR). It adopts a polyglot persistence model for the underlying data store and exposes heterogeneous data through the Open Data Protocol (OData), which is a candidate implementation of the Ud interface defined in the UDC architecture. With the introduction of polyglot persistence, multiple data stores can be used within the CSDR and disparate network data sources can access heterogeneous data sets using OData as a standard communications protocol. As the CSDR persistence model becomes more complex due to the inclusion of more storage technologies, polyglot persistence ensures a consistent conceptual view of these data sets through OData. Importantly, the CSDR prototype was integrated into a popular open-source implementation of the core part of an IMS network known as the Open IMS Core. The successful integration of the prototype demonstrates its ability to manage and expose a consolidated view of heterogeneous subscriber data, which are generated and used by different RCS services deployed within IMS

Preventing Distributed Denial-of-Service Attacks on the IMS Emergency Services Support through Adaptive Firewall Pinholing

Emergency services are vital services that Next Generation Networks (NGNs) have to provide. As the IP Multimedia Subsystem (IMS) is in the heart of NGNs, 3GPP has carried the burden of specifying a standardized IMS-based emergency services framework. Unfortunately, like any other IP-based standards, the IMS-based emergency service framework is prone to Distributed Denial of Service (DDoS) attacks. We propose in this work, a simple but efficient solution that can prevent certain types of such attacks by creating firewall pinholes that regular clients will surely be able to pass in contrast to the attackers clients. Our solution was implemented, tested in an appropriate testbed, and its efficiency was proven.Comment: 17 Pages, IJNGN Journa

Context-adaptive learning designs by using semantic web services

IMS Learning Design (IMS-LD) is a promising technology aimed at supporting learning processes. IMS-LD packages contain the learning process metadata as well as the learning resources. However, the allocation of resources - whether data or services - within the learning design is done manually at design-time on the basis of the subjective appraisals of a learning designer. Since the actual learning context is known at runtime only, IMS-LD applications cannot adapt to a specific context or learner. Therefore, the reusability is limited and high development costs have to be taken into account to support a variety of contexts. To overcome these issues, we propose a highly dynamic approach based on Semantic Web Services (SWS) technology. Our aim is moving from the current data- and metadata-based to a context-adaptive service-orientated paradigm We introduce semantic descriptions of a learning process in terms of user objectives (learning goals) to abstract from any specific metadata standards and used learning resources. At runtime, learning goals are accomplished by automatically selecting and invoking the services that fit the actual user needs and process contexts. As a result, we obtain a dynamic adaptation to different contexts at runtime. Semantic mappings from our standard-independent process models will enable the automatic development of versatile, reusable IMS-LD applications as well as the reusability across multiple metadata standards. To illustrate our approach, we describe a prototype application based on our principles

Learning Design and Service Oriented Architectures:a mutual dependency?

This paper looks at how the concept of reusability has gained currency in e-learning. Initial attention was focused on reuse of content, but recently attention has focused on reusable software tools and reusable activity structures. The former has led to the proposal of service-oriented architectures, and the latter has seen the development of the Learning Design specification. The authors suggest that there is a mutual dependency between the success of these two approaches, as complex Learning Designs require the ability to call on a range of tools, while remaining technology neutral. The paper describes a project at the UK Open University, SLeD, which sought to develop a Learning Design player that would utilise the service-oriented approach. This acted both as a means of exploring some of the issues implicit within both approaches and also provided a practical tool. The SLeD system was successfully implemented in a different university, Liverpool Hope, demonstrating some of the principles of re-use

DRIVER Technology Watch Report

This report is part of the Discovery Workpackage (WP4) and is the third report out of four deliverables. The objective of this report is to give an overview of the latest technical developments in the world of digital repositories, digital libraries and beyond, in order to serve as theoretical and practical input for the technical DRIVER developments, especially those focused on enhanced publications. This report consists of two main parts, one part focuses on interoperability standards for enhanced publications, the other part consists of three subchapters, which give a landscape picture of current and surfacing technologies and communities crucial to DRIVER. These three subchapters contain the GRID, CRIS and LTP communities and technologies. Every chapter contains a theoretical explanation, followed by case studies and the outcomes and opportunities for DRIVER in this field

GRIDCC - Providing a real-time grid for distributed instrumentation

The GRIDCC project is extending the use of Grid computing to include access to and control of distributed instrumentation. Access to the instruments will be via an interface to a Virtual Instrument Grid Service (VIGS). VIGS is a new concept and its design and implementation, together with middleware that can provide the appropriate Quality of Service (QoS), is a key part of the GRIDCC development plan. An overall architecture for GRIDCC has been defined and some of the application areas, which include distributed power systems, remote control of an accelerator and the remote monitoring of a large particle physics experiment, are briefly discussed.E