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This paper aims to discuss problems, requirements and current trends for deploying group communication in real‐world scenarios from an integrated perspective.

The Hybrid Shared Tree is introduced – a new architecture and routing approach to combine network – and subnetwork‐layer multicast services in end‐system domains with transparent, structured overlays on the inter‐domain level.

The paper finds that The Hybrid Shared Tree solution is highly scalable and robust and offers provider‐oriented features to stimulate deployment.

A straightforward perspective is indicated in the paper for a mobility‐agnostic routing layer for future use.

Ionic contaminations, especially flux residues due to manufacturing, cause various faults and failures of printed circuits during service. The contamination (µg‐eq NaCI), surface insulation resistance (SIR), electromigration and corrosion caused by flux residues of six different fluxes (categories: F‐SW26, F‐SW32 and F‐SW34 according to DIN 8511) have been investigated. The main effort was applied to the investigation of electromigration, which is understood as the formation of short circuits by metallic bridges between two conductors of different voltage.

The paper, aims to introduce an educational content management system Hypermedia Learning Objects System (hylOs), which is fully compliant to the IEEE LOM eLearning object metadata standard. Enabled through an advanced authoring toolset, hylOs allows the definition of instructional overlays of a given eLearning object mesh.

In educational content management, simple file distribution is considered insufficient. Instead, IEEE LOM standardised eLearning objects have been well established as the basic building blocks for educational online content. They are nicely suited for self‐explorative learning approaches within adaptive hypermedia applications. Even though eLearning objects typically reside within content repositories, they may propagate metadata relations beyond repository limits. Given the explicit meaning of these interobject references, a semantic net of content strings can be knotted, overlaying the repository infrastructure.

Based on a newly introduced ontological evaluation layer, meaningful overlay relations between knowledge objects are shown to derive autonomously. A technology framework to extend the resulting semantic nets beyond repository limits is also presented.

This paper provides proof of concept for the derivation and use of semantic content networks in educational hypermedia. It thereby opens up new directions for future eLearning technologies and pedagogical adoption.

The paper illustrates capabilities of the hylOs eLearning content management. The hylOs is built upon the more general Media Information Repository (MIR) and the MIR Adaptive Context Linking Environment (MIRaCLE): its linking extension. MIR is an open system supporting the standard XML, CORBA and JNDI. hylOs benefits from manageable information structures, sophisticated access logic and high‐level authoring tools like the eLO editor responsible for the semi‐manual creation of meta data and WYSIWYG like XML–content editing, allowing for rapid distributed content development.

Over the last few years, networking technologies and distributed information systems have moved up the OSI layer and are established well within application‐centric middleware. Most recently, content overlay networks have matured, incorporating the semantics of data files into their self‐organisational structure with the aim of optimising data‐centric distributed indexing and retrieval. This paper elaborates a corresponding concept of semantic structuring for educational content objects. It introduces and analyses the autonomous generation and educational exploitation of semantic content nets, providing proof of concept by a full‐featured implementation within the hylOs educational content management system.

This paper aims to compare internet measurement data obtained from Skitter, Ark and Dimes by analyzing the internet node degree distributions and correlations at IP node and router level. Further on, it is intended to analyze implications of the internet structure as attained in both its core and edge vicinities.

This comparative analysis was enabled by a data conversion and processing tool‐chain implemented as an extension to the BRITE topology generator which is also introduced.

The results show significant differences in higher nodal degrees. Correlation analysis indicates that DIMES scans discover internet links to a fairly uniform degree, while parts remain invisible within Skitter and Ark data. Mid‐range, oscillating spatial autocorrelations are discovered as a signature of memory effects in internet topology.

Mobile multicast routing performance is quantized by the number of states minimally required for servicing listener or sender mobility. Results show a surprisingly low mobility overhead compared with general multicast forwarding state management. As continuous mobility handovers necessarily occur between access routers located in geographic vicinity, the hypothesis is investigated that geographically adjacent edge networks attain a reduced network distances compared with arbitrary internet nodes. The evaluation of edge distance distributions in different regions for IP ranges, clustered according to their geographic location, reveals a stable correlation of geographic and network proximity at internet edges.

The internet topology has evolved over the past decades in an evolutionary process and continues to grow. Recently, it has attracted much attention from the networking and physics communities, as it forms a unique operational instance of a planetary‐scale network environment. Several measurement projects observing the internet have been undertaken over the past years, out of which Skitter, its successor Archipelago (Ark) and Dimes have been established as continuous recordings of the vivid process of network formation.

This paper deals with a cost‐related evaluation and a comparison of the problems that arise on pure IP networks (i.e. big fat routers), IP over static optical networks (i.e. IP over synchronous digital hierarchy/optical transport network (SDH/OTN)) and IP over ASON/GMPLS‐based dynamic optical network architectures. The aim is to develop easy‐to‐use CAPEX models, which can be evaluated using statistical parameters to describe the actual network and the traffic characteristics. Since there are no experimental results on these statistical parameters that can be practically used in real networks, the CAPEX model should be not only general, but also scalable enough to evaluate the network cost in extreme situations.

In this paper, the comparative CAPEX models are developed (in the framework of the IST Project MUPBED – Multi‐Partner European Test Beds for Research Networking) and the practical parameters are defined. Then the models are applied for the cost evaluation of a pan‐European research network based on the GÉANT2 network topology to validate the simplified comparison technique that is proposed.

The simulation results prove, on one hand, the applicability of the simplified cost models and on the other hand, the cost efficiency of the “IP over ASON/GMPLS” architecture.

This paper deals with a cost‐related evaluation and a comparison of the problems that are arise on pure IP networks, IP over static optical networks and IP over ASON/GMPLS‐based dynamic optical network architectures.

This paper aims to present the outcome of the i2CAT Foundations' research and innovation projects that use JXTA P2P technology to share audiovisual content.

The project consisted of designing and developing a distributed application named eRuc that allows management and sharing of audiovisual content.

The paper finds that JXTA is suitable to develop P2P applications that share audiovisual files or that interact with different kind of devices. JXTA services and protocols provide an easy integration with other P2P services and a gain of independence from the topology of the physical network (NAT, firewalls, etc.).

High‐quality streaming requires specifically designed P2P architectures. Further testing needs to be performed to evaluate whether the use of JXTA, together with proven, efficient P2P streaming architectures, affect the efficiency of the P2P streaming system.

P2P technologies have proven to be very efficient for some kind of applications. However, there are no standard frameworks for interoperability and application development may become difficult. JXTA P2P technologies facilitate application development and integration. The authors have used JXTA in different scenarios related with audiovisual content sharing and have proven its suitability. The current work is focused in P2P streaming. Previous literature suggests that there are some proven architectures for P2P life streaming. Using JXTA together with them may prove if JTXA is suitable for applications that require high bandwidth and minimum delay.

The paper provides information of value to information management and technology professionals.

This paper aims to examine the design and implementation of an advanced ToIP platform for the interconnection of ToIP operators based on the concept of multilateral peering, with a special focus on the design requirements and implementation.

Based on the key design requirements of a ToIP peering platform analysed at the beginning of the document, an open source‐based network architecture is proposed. Subsequently, a detailed explanation of the elements and their functionalities that integrate both core platform and management platform is presented.

The paper finds that open source‐based ToIP platforms provide a cheap solution for deploying ToIP services such as ToIP peering. Although not as stable as hardware‐based ToIP platforms, software‐based platforms provide a very scalable high‐performance solution for delivering customised ToIP services.

The paper studies the implementation of advanced VoIP services such as video telephony and the call termination in public switched telephony network or mobile networks.

The deployment of an experimental ToIP peering platform in Catalonian will help to the large‐scale adoption of ToIP by both enterprise and residential customers. Furthermore, operators can reduce both capital and operating expenditures if they exchange traffic through the ToIP peering platform, reducing, thus, the cost of ToIP calls to end users.

This paper aims to outline considerations for trust management between established national identity federations in education and research. It also aims to discuss policy issues related to cross‐federation and to compare existing academic identity federations. The paper seeks to investigate Nordic national federations and to introduce the Kalmar Union as a means of interconnecting the Nordic federations.

The paper discusses various issues in the policy of a cross‐federation, and suggests further work for developing the Kalmar Union Charter.

The paper finds that the technology used in federated identity management becomes more and more standardised, the technological challenges in making cross‐federations become fewer. Therefore, the remaining obstacles seem to be missing legislative know‐how, causing lack of sound information for decision makers. Thus, in an identity federation, trust establishment is, in the first place, a policy issue, not a technical one.

In recent years, several identity federations have been established in higher education around the world. Existing federations have a national scope, but the need for cross‐border services has led to the first interconnects of national federations. The Kalmar Union has been established as a cross‐federation of the Nordic academic identity federations.