Publications

This is a list of almost all my publications. Some recent ones may be missing as this list is kept manually. For some insight regarding the entries in this list, please check my Google Scholar Citation profile

Publications: 99 ( Books : 2, Journal articles : 35, Book chapters : 2, Conference papers : 58, Master thesis : 1 )
Cites: ( Updated )

2020

A Parser to Support the Definition of Access Control Policies and Rules Using Natural Languages

Blockchain structures to guarantee logging integrity of a digital platform to support community-dwelling older adults

Forecasting Appliances Failures: A Machine-Learning Approach to Predictive Maintenance

EAP-SH: An EAP authentication protocol to integrate Captive Portals with 802.11i

2019

A Network Service for Preventing Data Leakage from IoT Cloud-assisted Equipment

Abstract

The fact that most IoT solutions are provided by third parties, along with the pervasiveness of the collected data, raises privacy and security concerns. There is a need to verify which data is being sent to the third party, as well as preventing those channels from becoming an exploitation avenue. We propose to use existing API definition languages to create contracts which define the data that can be transmitted, their format and constraints. To verify the compliance with these contracts, we propose a Network Service architecture which validates REST-like API requests/responses against a Swagger schema. We deal with encrypted traffic using an Service Function Chaining (SFC)-enabled Man-in-the-Middle (MITM), allowing verifications in "real-time." We devised a Proof of Concept and showed that we were able to detect (and stop) contract violations.

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Access Control for Social Care Platforms Using Fast Healthcare Interoperability Resources

Abstract

The definition of authorization policies is essential to prevent information misuse and to guarantee that only authorized personnel can access specific information. Since not everyone is familiar with special purpose languages, an interpretation tool can allow the management of policies and rules using natural languages. This paper focuses on a parser developed as a component of a platform to support the care of community-dwelling older adults, the SOCIAL platform, allowing to create, read, update and delete authorization policies and rules, using natural languages.

Cites: 2 (see at Google Scholar)

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Cloud-Centric Networking Using Virtualization and Resource Sharing

Developing solutions for pay-as-you-throw information systems

Fault-Tolerance in the Scope of Software-Defined Networking (SDN)

Abstract

Fault-tolerance is an essential aspect of network resilience. Fault-tolerance mechanisms are required to ensure high availability and high reliability in systems. The advent of software-defined networking (SDN) has both presented new challenges and opened new paths to develop novel strategies, architectures, and standards to support fault-tolerance. In this survey, we address SDN fault-tolerance and discuss the OpenFlow fault-tolerance support for failure recovery. We highlight the mechanism used for failure recovery in Carrier-grade networks that includes detection and recovery phases. Furthermore, we highlight SDN-specific fault-tolerance issues and provide a comprehensive overview of the state-of-the-art SDN fault-tolerance research efforts. We then discuss and structure SDN fault-tolerance research according to three distinct SDN planes (i.e., data, control, and application). Finally, we conclude enumerating future research directions for SDN fault-tolerance development.

Cites: 2 (see at Google Scholar)

Integration of the Captive Portal paradigm with the 802.1 X architecture

Abstract

In a scenario where hotspot wireless networks are increasingly being used, and given the amount of sensitive information exchanged on Internet interactions, there is the need to implement security mechanisms that guarantee data confidentiality and integrity in such networks, as well as the authenticity of the hotspot providers. However, many hotspots today use Captive Portals, which rely on au- thentication through Web pages (thus, an application-level authentication approach) instead of a link-layer approach. The consequence of this is that there is no security in the wireless link to the hotspot (it has to be pro- vided at upper protocol layers), and is cumbersome to manage wireless access profiles (we need special applications or browsers’ add-ons to do that). This work exposes the weaknesses of the Captive Portals’ paradigm, which does not follow a unique nor standard approach, and describes a solution that intends to suppress them, based on the 802.1X architec- ture. This solution uses a new EAP-compliant protocol that is able to integrate an HTTP-based registration or authentication with a Captive Portal within the 802.1X authentication framework.

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Logging Integrity with Blockchain Structures

Cites: 2 (see at Google Scholar)

Network Functions Virtualization: The Long Road to Commercial Deployments

Abstract

Network operators are under pressure to offer efficient network-based services while keeping service deployment costs to a minimum. Network Functions Virtualization (NFV) can potentially revolutionize network-based services bringing low deployment costs for network operators. NFV has been introduced to ultimately extend the non-proprietary and open-standardbased model to network and service deployments, significant improvements to today’s proprietary locked implementations. Notwithstanding the continuous efforts of both academia and industry to support the NFV paradigm, the current NFV solutions offered are still in its infancy. In this survey, we provide a detailed background of NFV to establish a comprehensive understanding of the subject, ranging from the basics to more advanced topics. Moreover, we offer a comprehensive overview of the NFV main concepts, standardization efforts, benefits of NFV and discuss the NFV architecture as defined by the European Telecommunications Standardization Institute (ETSI). Furthermore, we discuss NFV applicability and current open source projects. We then highlight NFV requirements, design considerations, and developmental architectural impairments and barriers to commercial NFV deployments. Finally, we conclude enumerating future directions for NFV development.

Cites: 7 (see at Google Scholar)

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QoS-Aware Service Continuity in the Virtualized Edge

Abstract

5G systems are envisioned to support numerous delay-sensitive applications such as the tactile Internet, mobile gaming, and augmented reality. Such applications impose new demands on service providers in terms of the quality of service (QoS) provided to the end-users. Achieving these demands in mobile 5G-enabled networks represent a technical and administrative challenge. One of the solutions proposed is to provide cloud computing capabilities at the edge of the network. In such vision, services are cloudified and encapsulated within the virtual machines or containers placed in cloud hosts at the network access layer. To enable ultrashort processing times and immediate service response, fast instantiation, and migration of service instances between edge nodes are mandatory to cope with the consequences of user's mobility. This paper surveys the techniques proposed for service migration at the edge of the network. We focus on QoS-aware service instantiation and migration approaches, comparing the mechanisms followed and emphasizing their advantages and disadvantages. Then, we highlight the open research challenges still left unhandled.

Cites: 2 (see at Google Scholar)

Safeguarding from abuse by IoT vendors: Edge messages verification of cloud-assisted equipment

Abstract

The fact that most IoT solutions are provided by 3rd-parties, along with the pervasiveness of the collected data, raises privacy and security concerns. There is a need to verify which data is being sent to the 3rd-party, as well as preventing those channels from becoming an exploitation avenue. We propose to use existing API definition languages to create contracts which define the data that can be transmitted, in what format, and with which constraints. To verify the compliance with these contracts, we propose a converging "Multi-Access Edge Computing" architecture which validates RESTalike API requests/responses against a Swagger schema. We deal with encrypted traffic using an SFC-enabled Man-in-the-Middle, allowing us to do verifications in "real-time". We devised a Proof of Concept and shown that we were able to detect (and stop) contract violations.

SCoTv2: Large Scale Data Acquisition, Processing, and Visualization Platform

User-Centric and Information-Centric Networking and Services: Access Networks, Storage and Cloud Perspective

Abstract

User-Centric Networks (UCN) and Information-Centric Networks (ICN) are new communication paradigms to increase the efficiency of content delivery and also content availability. In this new concept, the network infrastructure actively contributes to content caching and distribution. This book presents the basic concepts of UCN and ICN, describes the main architecture proposals for these networks, and discusses the main challenges to their development. The book also looks at the current challenges for this concept, including naming, routing and caching on the network-core elements, several aspects of content security, user privacy, and practical issues in implementing UCN and ICN.

Cites: 1 (see at Google Scholar)

Wastes: Solutions, Treatments and Opportunities III: Selected Papers from the 5th International Conference Wastes 2019, September 4-6, 2019, Lisbon, Portugal

Cites: 7 (see at Google Scholar)

A Comparative Study of LoRaWAN, SigFox, and NB-IoT for Smart Water Grid

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Network Slicing Security: Challenges and Directions

Abstract

Network slicing emerges as a key technology in next generation networks, boosted by the integration of software-defined networking and network functions virtualization. However, while allowing resource sharing among multiple tenants, such networks must also ensure the security requirements needed for the scenarios they are employed. This letter presents the leading security challenges on the use of network slices at the packet core, the solutions that academy and industry are proposing to address them, pointing out some directions that should be considered.

Cites: 6 (see at Google Scholar)

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Predictive Maintenance System for Efficiency Improvement of Heating Equipment

Abstract

Heating appliances such as HVAC systems consume around 48% of the energy power spent on household appliances every year 1. With this in mind, it is relevant to increase the efficiency of those solutions. Moreover, a malfunctioning device can increase this value even further. Thus, there is a need to develop methods that allow the identification of eventual failures before they occur. This is only achievable when services capable of analyzing data, interpret it and obtaining knowledge from it, are created. This paper presents an infrastructure that supports the inspection of failure detection in boilers, making viable to forecast faults and errors. A major part of the work is data analysis and the creation of procedures that can process it. The main goal is creating an efficient system able to identify, predict and notify the occurrence of failure events. Our fundamental contribution is the possibility to scale the system to others datasets, being able to resolve different Big Data issues.

2018

Very large scale high performance computing and instrument management for high availability systems through the use of virtualization at the Square Kilometre Array (SKA) telescope

Abstract

The Square Kilometer Array (SKA) Telescope, is an ongoing project set to start its building phase in 2018 and be ready for first light in 2020. The first part of the project, the SKA1 will be comprised of 130.000 low frequency antennas (50 MHz to 350 MHz) and 200 mid frequency antennas (350 MHz to 15.5 GHz). The SKA1 will produce a raw data rate of ~10 Tb/s, require a computing power of 100 Pflop/s and an archiving capacity of hundreds of PB/year. The next phase of the project, the SKA2, is going to increase the number of both low and mid antennas by a factor of 10 and increase the computing requirements accordingly. The key requirements for the project are a very demanding availability of 99.9%, computing scalability and result reproducibility. We propose an approach to enforce these requirements - with an optimal use of resources - by using highly distributed computing and virtualization technologies.

Keywords

square kilometer array, reproducibility, telescope manager, ska, virtualization, high performance computing, hpc, radio astronomy

An SFC-enabled approach for processing SSL/TLS encrypted traffic in Future Enterprise Networks

Abstract

In this paper, we propose an architecture based on NFV and SDN which allows to balance traffic analysis techniques using a Classifier. It steers flows to the appropriate Service Function Chaining (to open traffic or not) according to network requirements (such as, effectiveness, flexibility, scalability, performance, and privacy). The SSL/TLS traffic processing is carried-out by the centerpiece of this work, the SFC-enabled MITM. A Proof-of-Concept was conducted (focusing on our SFC-enabled MITM) which showed that functionalities lost due to encryption (Content Optimization, Caching, Network Anti-virus, and Content Filter) were recovered when processing opened traffic within its Service Function Chains. We also evaluated its impact on performance. The results show that cipher suite overhead plays a role but can be mitigated, the Classifier can alleviate the performance overhead of different traffic analysis techniques, network functions have lower impact to performance, and Service Function Chaining length influences page load time.

Cites: 3 (see at Google Scholar)

Human-Centric Design of Unified Communications: e-Collaboration Features

Abstract

This article describes a co-design process in the context of user experience (UX) and usability testing and analysis of a first proof of concept of e-collaboration features based on unified communications, co-designed within an organization aiming to optimize users' communication cognitive load. An initial digital prototype with a detailed graphical interface, and simulated user narratives was established and the qualitative validation process is described and discussed. The implemented R&D process is mainly supported on user-centred design (UCD) methodology, namely action research with service design thinking method and co-design techniques. Qualitative data was gathered with concurrent think-aloud activities (CTA) stimulated by user experience expectation questions, observation notes, with integration in an eye tracking technology system. The UCD process and results are discussed, substantiating the added value due to the individual contributions and consequent usefulness of a final unified communication service for the organization.

Orchestrating an SFC-enabled SSL/TLS traffic processing architecture using MANO

Abstract

The heterogeneity of 5G requirements commands more complex network architectures, imposing the need for network orchestration. ETSI MANO is the standard which defines a common framework for vendors and operators to integrate their orchestration efforts. In this paper, we evaluated how an ETSI MANO compliant orchestrator (OSM) fares while orchestrating an SFC-enabled SSL/TLS encrypted traffic processing architecture, which supports both edge and cloud deployments. A quantitative evaluation was carried-out, which assessed the responsiveness and overheads of OSM, as well as the actual functionality of our SSL/TLS processing architecture (with edge computing components). A qualitative evaluation was also carried-out, providing insight into the maturity of the current OSM release, what works well, what requires workarounds, and the actual limitations. A demonstration of the architecture evaluated in this work was accepted as a contribution to the ETSI OSM PoC Framework.

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Resource discovery for distributed computing systems: A comprehensive survey

Abstract

Large-scale distributed computing environments provide a vast amount of heterogeneous computing resources from different sources for resource sharing and distributed computing. Discovering appropriate resources in such environments is a challenge which involves several different subjects. In this paper, we provide an investigation on the current state of resource discovery protocols, mechanisms, and platforms for large-scale distributed environments, focusing on the design aspects. We classify all related aspects, general steps, and requirements to construct a novel resource discovery solution in three categories consisting of structures, methods, and issues. Accordingly, we review the literature, analyzing various aspects for each category.

Cites: 14 (see at Google Scholar)

SKA telescope manager: a status update

Abstract

The international Square Kilometre Array (SKA) project to build two radio interferometers is approaching the end of its design phase, and gearing up for the beginning of formal construction. A key part of this distributed Observatory is the overall software control system: the Telescope Manager (TM). The two telescopes, a Low frequency dipole array to be located in Western Australia (SKA-Low) and a Mid-frequency dish array to be located in South Africa (SKA-Mid) will be operated as a single Observatory, with its global headquarters (GHQ) based in the United Kingdom at Jodrell Bank. When complete it will be the most powerful radio observatory in the world. The TM software must combine the observatory operations based at the GHQ with the monitor and control operations of each telescope, covering the range of domains from proposal submission to the coordination and monitoring of the subsystems that make up each telescope. It must also monitor itself and provide a reliable operating platform. This paper will provide an update on the design status of TM, covering the make-up of the consortium delivering the design, a brief description of the key challenges and the top level architecture, and its software development plans for tackling the construction phase of the project. It will also briefly describe the consortium’s response to the SKA Project’s decision in the second half of 2016 to adopt the processes set out by the Software Engineering Institute (SEI) for system architecture design and documentation, including a re-evaluation of its deliverables, documentation and approach to internal reviews.

Keywords

Teelscope Monitor and Control, Square Kilometre Array, Observatory Software, Telescope Software, Radio Astronomy

Cites: 1 (see at Google Scholar)

TM Services: an architecture for monitoring and controlling the Square Kilometre Array (SKA) Telescope Manager (TM)

Cites: 3 (see at Google Scholar)

Shaping Future Reliable and Critical Communications Using Virtualization Technologies

2017

A survey on cooperative MAC protocols in IEEE 802.11 wireless networks

Cites: 16 (see at Google Scholar)

Click-on-osv: A platform for running click-based middleboxes

Cites: 12 (see at Google Scholar)

Decentralized Resource Discovery and Management for Future Manycore Systems

HARD: Hybrid adaptive resource discovery for jungle computing

Cites: 6 (see at Google Scholar)

Manycore simulation for peta-scale system design: Motivation, tools, challenges and prospects

Cites: 10 (see at Google Scholar)

PASMO: An open living lab for cooperative ITS and smart regions

Cites: 5 (see at Google Scholar)

Secure Decentralized IoT Infrastructure

Cites: 1 (see at Google Scholar)

Vehicular dataset for road assessment conditions

Cites: 1 (see at Google Scholar)

2016

A cyber infrastructure for the SKA Telescope Manager

Cites: 2 (see at Google Scholar)

ElCore: Dynamic elastic resource management and discovery for future large-scale manycore enabled distributed systems

Cites: 9 (see at Google Scholar)

Non-IP Multi-protocol Stack for Vehicular Communications

Cites: 1 (see at Google Scholar)

Policy-driven vCPE through dynamic network service function chaining

Cites: 10 (see at Google Scholar)

Power monitoring and control for large scale projects: SKA, a case study

Cites: 4 (see at Google Scholar)

Seamless integration of cloud and fog networks

Cites: 5 (see at Google Scholar)

SKA Telescope Manager (TM): status and architecture overview

Abstract

The SKA radio telescope project is building two telescopes, SKA-Low in Australia and SKA-Mid in South Africa respectively. The Telescope Manager is responsible for the observations lifecycle and for monitoring and control of each instrument, and is being developed by an international consortium. The project is currently in the design phase, with the Preliminary Design Review having been successfully completed, along with re-baselining tomatch project scope to available budget. This report presents the status of the Telescope Manager work, key architectural challenges and our approach to addressing them.

Keywords

SKA TM status, Telescope Manager, TM architecture, observation management, scalability, specifications-driven approach, resource capabilities, telescope monitoring and control

Cites: 6 (see at Google Scholar)

2015

A specification-based anycast scheme for scalable resource discovery in distributed systems

Cites: 2 (see at Google Scholar)

Dynamic, scalable and flexible resource discovery for large-dimension many-core systems

Abstract

Abstract Future large scale systems will execute novel operating systems running across many chips with many cores. In this highly distributed environment, resource discovery is an important building block. Resource discovery aims to match the application’s demands to the existing (distributed) resources, by discovering and finding resources at run-time, and then selecting the best resource that matches the application running requirements. The main contribution of this paper is the design and evolution of a highly scalable, highly flexible, resource discovery model for such heterogeneous environments. The model is based on self-organizing processing resources in the system according to a hierarchical resource description where each group of resources has a local directory that collects and keeps the information of the underlying resource members (cores) in different layers. Operationally, at each layer, it consists of a peer-to-peer architecture of modules that, by interacting with each other, provide a global view of the resource availability in a large, dynamic and heterogeneous distributed environment. The proposed resource discovery model provides the adaptability and flexibility to perform complex querying by supporting a large set of significant querying features (such as multi-dimensional, range and aggregate querying) while supporting exact and partial matching, both for static and dynamic object contents. The paper demonstrates by simulation how the proposed model can deal with issues such as scalability, efficiency and adaptability of resource discovery in future many-core systems which are the major challenges in the current state of the art. The simulation shows that the proposed resource discovery model can be applied to arbitrary scales of dynamicity, both in terms of complexity and of scale, positioning this proposal as a good architecture for future many-core systems.

Cites: 9 (see at Google Scholar)

Smart Cloud of Things: an evolved IoT platform for Telco providers

Cites: 11 (see at Google Scholar)

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IMS Centric Communication Supporting WebRTC Endpoints

Cites: 4 (see at Google Scholar)

When science fiction turns to reality: Square Kilometre Array (SKA), the largest radio telescope ever imagined

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Benefits of metering and intelligent control in energy savings of public street ligthing - UA Smart Campus use case

Seamless integration of Cloud and Fog networks

Abstract

This work provides a way to merge Cloud Computing infrastructures with traditional or legacy network deployments, leveraging the best in both worlds and enabling a logically centralized control for it. A solution is proposed to extend existing Cloud Computing software stacks so they are able to manage networks outside the Cloud Computing infrastructure, by extending the internal, virtualized network segments. This is useful in a variety of use cases such as incremental Legacy to Cloud network migration, hybrid virtual/traditional networking, centralized control of existing networks, bare metal provisioning, and even offloading of advanced services from typical home gateways into the operator. By using what is called External Drivers, any organization can develop their own driver to support new, specific networking equipment. Our concept solution is prototyped on top of OpenStack, including changes to the API, command line interface and other mechanisms. Test results indicate that there are low penalties on latency and throughput, and that provisioning times are reduced in comparison with similar maintenance operations on traditional computer networks.

Cites: 5 (see at Google Scholar)

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Toward a telco cloud environment for service functions

Abstract

Deploying service functions, SFs, is an essential action for a network provider. However, the action of creating, modifying and removing network SFs is traditionally very costly in time and effort, requiring the acquisition and placement of specialized hardware devices and their interconnection. Fortunately, the emergence of concepts like cloud computing, SDN, and ultimately NFV is expected to raise new possibilities for the management of SFs with a positive impact in terms of agility and cost. From a telco viewpoint these concepts can help to both reduce OPEX and open the door to new business opportunities. In this article, we identify how téleos can benefit from the abovementioned paradigms, and explore some of the aspects that still need to be addressed in the NFV domain. We focus on two major aspects: enabling telco infrastructures to adopt this new paradigm, and orchestrating and managing SFs toward telco-ready cloud infrastructures. The technologies we describe enable a telco to deploy and manage SFs in a distributed cloud infrastructure. In this context, the Cloud4NFV platform is presented. Special attention is given to the way SFs are modeled toward cloud infrastructure resources. In addition, we explore the ability to perform service function chaining as one of the fundamental features in the composition of SFs. Finally, we describe a proof of concept that demonstrates how a telco can benefit from the described technologies.

Keywords

cloud computing;telecommunication computing;telecommunication industry;Cloud4NFV platform;NFV domain;OPEX;SDN;agility;business opportunities;cloud computing;cloud infrastructure resources;distributed cloud infrastructure;network provider;positive impact;service function chaining;service functions;specialized hardware devices;telco cloud environment;telco infrastructures;telco viewpoint;telco-ready cloud infrastructures;Business;Cloud computing;Ports (Computers);Quality of service;Telecommunication standards;Wide area networks

Cites: 100 (see at Google Scholar)

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2014

CloudThinking as an Intelligent Infrastructure for Mobile Robotics

Abstract

Mobile robotics is a transforming field that presents a varying set of challenges. The discussion on the autonomy of (self-powered) robots is not settled, and as the communication infrastructure evolves, centralized concepts become more attractive over distributed concepts. This paper presents the CloudThinking architecture applied to intelligent cloud-based robotic operation. CloudThinking offloads most of complex robotic tasks to a central cloud, which retrieves inputs from the environment as a whole in order to instruct the robots to perform its actions. CloudThinking is a natural approach to the orchestration of multiple specialized robotic systems, defining the best mechanisms for reaching a goal. Furthermore, this architecture provides a set of automatic features which can be useful for application developers. These features can fully exploit novel cloud tools development as it becomes available, providing a time-resilient infrastructure of easy upgrade. The resulting approach has the potential to create a different set of market for robotic application developers.

Cites: 13 (see at Google Scholar)

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Unified Platform for M2M Telco Providers

Abstract

Although many environments are powered by M2M solutions, users do not have a simple way to gather their collective knowledge and program devices’ behaviour. Also, Telco providers still lack proper components for enabling integrated services over their networks. We present the final architecture of the APOLLO project, which delivers a enhanced M2M platform encompassing sensors, management and applications platform for a major Telco provider. APOLLO builds on top of ETSI M2M specifications and rich service execution environments providing easy orchestration of services to end-users.

Keywords

IoT; IoS; Service Orchestration; Telco; M2M

Cites: 5 (see at Google Scholar)

Electronic shelf labeling employing visible light communication concepts

Abstract

This paper discusses the usage of visible light communication concepts for Electronic Shelf Labeling Devices (ESLD), using unmodified smart phones. Visible light communication enables novel and interesting approaches to the design of these devices, able to address application scenarios that have not yet been explored. Amongst these novel approaches, it is worthwhile highlighting the feasibility to offer easy integration of social networking concepts, and the inherent ability to explore communication means supported by the lighting installation. The achieved results show that these novel electronic shelf labeling devices are able to offer good quality of service support, with nearly optimal bit error rates under normal illumination levels.

Cites: 3 (see at Google Scholar)

A self-organizing and self-configuration algorithm for resource management in service-oriented systems

Abstract

With the ever increasing deployment of service oriented distributed systems in large-scale and heterogeneous computing environments, clustering and communication overlay topology design has become more and more important to address several challenging issues and conflicting requirements, such as efficient scheduling and distribution of services among computing resources, reducing communication cost between services, high performance service and resource discovery while considering both inter-service and inter-node properties and also increasing the load distribution and the load balance. In this paper, a four-stage hierarchical clustering algorithm is proposed which automates the process of the optimally composing communicating groups in a dynamic way while preserving the proximity of the nodes. The simulation results show the performance of the algorithm with respect to load balance, scalability and efficiency.

Keywords

Aggregates;Clustering algorithms;Heuristic algorithms;Merging;Peer-to-peer computing;Receivers;Switches;Resource Discovery;Resource Management;Self-adaptation;Self-configuration;Self-deployment;Service-oriented Systems

Cites: 9 (see at Google Scholar)

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A sustainable approach to large ICT science based infrastructures; the case for radio astronomy

Abstract

Large sensor-based infrastructures for radio astronomy will be among the most intensive data-driven projects in the world, facing very high power demands. The geographically wide distribution of these infrastructures and their associated processing High Performance Computing (HPC) facilities require Green Information and Communications Technologies (ICT): a combination is needed of low power computing, power and byte efficient data storage, local data services, Smart Grid power management, and inclusion of Renewable Energies. Here we outline the major characteristics and innovation approaches to address power efficiency and long-term power sustainability for radio astronomy projects, focusing on Green ICT for science.

Cites: 4 (see at Google Scholar)

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Cooperation Metric for IEEE 802.11 Wireless Networks

Abstract

A key design issue in relay based cooperative wireless networks is the design of an appropriate metric for relay selection algorithms. In most cooperative protocols designed for IEEE 802.11 networks, the relay selection metric is based on reducing the transmission delay of relay links. The bandwidth efficiency provided by this metric is beneficial for applications communicating at high data rate, however not all applications will benefit from this simple approach. In this paper, a novel cooperative metric is proposed, which in addition to bandwidth, also considers link reliability and link stability, especially useful in mobile scenarios, and for time sensitive service applications. The proposed metric is applied to the well-known CoopMAC protocol. Simulation results indicate a strong correlation between network performance and proposed cooperative metric.

Keywords

access protocols;cooperative communication;relay networks (telecommunication);telecommunication standards;CoopMAC protocol;IEEE 802.11 wireless networks;bandwidth efficiency;cooperation metric;cooperative metric;cooperative protocols;link reliability;link stability;mobile scenarios;network performance;relay based cooperative wireless networks;relay links;relay selection algorithms;relay selection metric;time sensitive service applications;transmission delay;Bandwidth;Delays;IEEE 802.11 Standards;Protocols;Relays;Reliability

Cites: 3 (see at Google Scholar)

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2013

An open source software forge for European projects

Abstract

{Open Source is an increasingly interesting vehicle for dissemination of project results within the R&D andICT FP7 communities. PROSE, an FP7 ICT project, is promoting open source adoption by creating a software forge that provides project management, source code hosting, and development support for the ICT and European open source projects. In this paper we present the key requirements for a software forge resulting from a public consultation of projects in the European space, and the corresponding instantiation of an open source software forge, publicly available at opensourceprojects.eu. We also discuss the relevance of a centralized collaboration platform for European projects, and the value presented by such an approach as opposed to current source code repositories.}

Cites: 1 (see at Google Scholar)

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PROSE: Survey on requirements for hosting open source software projects

Abstract

Widespread use of free/libre/open source software (FLOSS) in European funded projects is vital to innovation transfer, but often, such software doesn’t enter general use. Legal issues, lack of business drivers, incomplete documentation and lack of knowledge about FLOSS are some of the most common reasons for this. PROSE, an EU-funded project tasked with promoting FLOSS, aims to provide a common cloud platform on which open source projects can be hosted and information shared. But how would such a platform work? And what would be its main requirements and features? PROSE turned to ICT FP7 participants for answers.

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Collaborative Relaying Strategies in Autonomic Management of Mobile Robotics

Abstract

Mobile robotics is a field that presents a surprising set of challenges to communications. One concept that can result in radically different solutions in mobile robotics is that of collaborative and cooperative communications. Cooperative techniques in wireless networks can enhance the performance of communication especially in cases where a small number of robots can be used to aid the establishment of reliable and efficient communication links. In this paper, we present a scenario for hybrid mobile robotics, where a small number of carriers are able to reposition nodes according to communication needs. We developed a common information management layer in order to coordinate cooperation (including communication aspects) between all units (information nodes and robots) according to high level self-established policies. We select IEEE 802.11 technology as the technology for the communication infrastructure and explore its potential for cooperative mobile environments in terms of power and spectrum efficiency presenting the rules required to reconfigure such a mobile robotic environment.

Cites: 6 (see at Google Scholar)

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2012

Architecture for orchestration of M2M services

Abstract

The past few years, miniaturization has allowed us to imbue computers into everyday devices. This in turn has enabled these devices to communicate with each other, and in doing so, allows us to collect a wealth of information, more accurately and with greater availability than ever before. This phenomenon is known as the Internet of Things. It allows smart environments to truly behave in an intelligent manner by using information collected from the devices mentioned above. However, it’s necessary to model how the gathered data will influence the behavior of a smart environment. This open problem can be approached as a machine to machine (M2M) orchestration. In this paper we present a new architecture for M2M orchestration. This new architecture will be based around a platform that creates orchestration processes through a graphical interface. Through this interface a business process execution language (BPEL) service will be made and deployed on an enter- prise service bus (ESB). Alongside this, we are also developing a collection of services that will be used for the purposes of implementing a smart environment.

Cites: 2 (see at Google Scholar)

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Demonstrating the AMazING Panel

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Energy Efficiency and Capacity Modeling for Cooperative Cognitive Networks

Abstract

Cooperative relaying has recently appeared as one of the widely recognized features for future wireless communication systems. The great potential of cooperative communication in increasing system capacity and enhancing power efficiency has attracted large efforts over the last few years. In this paper, we propose a Cooperation Loop as a reference model for all algorithms in relay based cooperative wireless networks. Using this model, we discuss cooperative relay based protocols in IEEE 802.11 standards and limits posed to cognitive approaches. We show the potential location area of relay nodes as well as the performance bounds of capacity gain, delay and power efficiency achieved in relay based scenarios for any cooperative cognitive algorithms.

Cites: 2 (see at Google Scholar)

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Experimentation made easy with the AMazING panel

Abstract

Experimental testbeds for evaluating solutions in computer networks, are today required as a complement to simulation and emulation. As these testbeds become larger, and accessible to a broader universe of the research community, dedicated management tools become mandatory. These tools ease the complex management of the testbed specific resources, while providing an environment for researchers to define their experiments with large flexibility. While there are currently several management tools, the research community is still lacking tools that smooth the experimentation workflow. These were key aspects that we considered when developing the management infrastructure for our wireless testbed(AMazING). We developed a experimentation support framework supported by an attractive GUI, automation and scripting capabilities, as well as experiment versioning and integrated result gathering and analysis.

Cites: 2 (see at Google Scholar)

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Mecanismos de Factura\cc\~ao Segura em Redes Auto-Organizadas

Multiplatform management of a Hard Real-Time Ethernet Switch

Abstract

The Hard Real-Time Ethernet Switch (HaRTES) allows using the same network to handle multiple traffic flows, without compromising the performance of real-time applications. Furthermore, it also provides flexible and on-line scheduling techniques with admission control capabilities, thus real-time communications flows can be added, removed and updated online with strict temporal isolation. However, HaRTES lacked a standard management interface to configure its parameters and view its status. This paper describes a multiprotocol (SNMP and NETCONF) management interface design, and implementation. It also presents a preliminary validation of the two management technologies.

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Towards a Cloud Service Broker for the Meta Cloud

Abstract

Cloud Computing provides computing resources, middleware and (web-based) software on an on-demand basis. This model helps customers saving costs and allows access to the latest technology. With the exponential growth of IT companies offering cloud services, deploying applications to the cloud has become a complex task to engage. Almost each and every provider has its own terminology, providers do not share the same (or even similar) API, and costs of operation greatly diverge according to provider, region or availability. This paper propounds a Cloud Service Broker (CSB), and describes an early prototype, where users are, intelligently and autonomously, aid to deploy, manage, monitor and migrate their applications in a cloud of clouds. A single API is required to orchestrate the whole process in tandem with two truly decoupled managers: a Platform as a Service Manager (PaaS Manager) and an Infrastructure as Service Manager (Iaas Manager). Users also interact with the CSB through a Web portal and a command-line interface.

Cites: 8 (see at Google Scholar)

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Establishment of Stackable Community Networks

Abstract

One of the research areas with increasing interest in the field of telecommunications, are the ones related to future telecommunication systems, both 4th generation and beyond. In parallel, during the last years, several concepts have been developed related to clustering of users according to their interested, in the form of community networks. Solutions proposed for these concepts tackle the challenges horizontally, for each layer of the communication stack, ranging from community based communication networks (e.g. Seattle Wireless, or Personal Telco), to interest networks based on peer-to-peer protocols. However, these networks are presented either as free joining, or overlay networks. In practice, the notion of a self-organized, service and community oriented network, with these principles embedded in its design principles, is yet to be developed. This work presents an novel instantiation of a solution in the area of community networks, with a underlying architecture which is fully service oriented, and envisions the support for multiple community networks in the same device. Considerations regarding security, trust and service availability for this type of environments are also taken. Due to the importance of resource management and access control, in the context of community driven communication networks, a special focus was given to the support of scalable and decentralized management and access control methods. For this purpose, it is presented a policy language which supports the creation and management of virtual communities. The language is not only used for mapping the social structure of the community members, but also to, following a distributed approach, manage devices, resources and services owned by each community member.

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Asynchronous Design Pattern for Many-Core and Cloud Operating Systems

Abstract

One of the key aspects for many-core and cloud operating systems is message passing communication. The networking aspect of this mechanism requires a high degree of concurrency to handle communicating with thousands of cores simultaneously in an efficient and scalable manner. Non-blocking interfaces allows us to efficiently use a core and gives us concurrency without multiple threads, this also minimizes context switch. We developed an asynchronous design pattern for operating systems written in C++. The framework uses only C++ language features (template metaprogramming), thus not requiring a custom compiler. The pattern provides a framework to develop and use asynchronous interfaces based on completion handlers. As the name implies, a completion handler is executed when the operation completes. The framework also provides queuing mechanism to serialize execution of handlers for synchronization purposes.

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2011

AMazING-Advanced Mobile wireless playGrouNd

User centric community clouds

Cites: 9 (see at Google Scholar)

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A Framework for User-centric Autonomic Management

Abstract

This paper presents a novel autonomic management framework for user-centric networks. The framework assumes users are directly involved, or have direct interest, on their communication system, and as such, place user-related constrains on the behavior of the system. Groups of interest, formed either implicitly or explicitly, by users are considered inside the community concept, which the framework supports. For the realization of this concept, we require a new knowledge and logic layer, which we describe. This framework has been instantiated and tested in a small environment. The results showed the added flexibility of our framework, and its ability to integrated diverse user requirements.

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Cooperative performance bounds of Wireless Local Area Networks

Abstract

In a Wireless Local Area Network (WLAN), capacity gain and delay reduction play a crucial role in system performance. In this paper, we focus on performance improvements when WLANs exploit the concept of cooperation among nodes. We propose a geometrical model to determine the potential location area of relay nodes. The analytical results are validated by simulation. Performance bounds and average of capacity gain and delay ratio are studied for different IEEE 802.11 standards.

Cites: 3 (see at Google Scholar)

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Metrics for optimal relay selection in cooperative wireless networks

Abstract

A key design issue in relay based cooperative wireless networks is the metrics used for relay selection. Internal operational parameters and network sensing parameters are two categories recently considered as decision factors for cooperation strategies. We focus on the impact of these potential sensing parameters as indicators of the effective cooperation, from the perspective of the network layer, namely: movement, medium access delay and medium delay ratio. Simulation results indicate a strong correlation between network performance and the proposed cooperative metrics. Novel solutions for cooperation should take these metrics into consideration in order to provide better network performance.

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Network Interfaces Flying over IP Networks

Abstract

We propose a novel method to export both interface control and data planes across different hosts, effectively enabling hardware specific control of network interfaces over the Internet, or from a host to its virtualized guests. Our solution is a major step towards distributed environments of heterogeneous communication systems, particularly relevant in the scope of custom system composition, remote development and testing, and is especially relevant when considering embedded or geographically constrained devices. Results obtained by our prototype implementation validate the effectiveness of the solution. We present a preliminary characterization of its impact, when considering traffic generation applications, when applied over an IEEE 802.11g communication medium.

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2010

Characterization of Unplanned Metropolitan Wireless Networks

Abstract

Mobile Internet penetration has grown steadily over the last few years. Although most of today's users have access through their 3G Mobile Operators, there are still regions that are under-covered for various reasons. Wireless Mesh Networks (WMN) can play an important role by providing the means to fully cover those underserved regions. Due to their intrinsic nature, WMN require a critical mass of nodes belonging to the mesh in order to be effective. In this paper we present a study conducted in Aveiro, Portugal which intends to draw some conclusions on the feasibility of deploying a WMN in small to medium cities based on the cooperation of its inhabitants and on off-the-shelf wireless equipment.

Cites: 1 (see at Google Scholar)

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2009

FastM in WMN: A Fast Mobility Support Extension for Wireless Mesh Networks

Abstract

In this paper we present a new extension to proactive routing protocols using a fast mobility extension, FastM, with the purpose of increasing handover performance in wireless mesh networks. With this new extension a new concept is created to integrate information between neighbor wireless mesh routers, managing locations of clients associated to wireless mesh routers in a certain neighborhood, and avoiding packet loss during handover. The proposed mobility protocol is able to optimize the handover process without imposing any modifications to the current IEE 802.11 MAC protocol and use unmodified clients. Results show the improved efficiency of the proposed scheme: metrics such as disconnection time, throughput, packet loss and control overhead are largely improved when compared to previous approaches.

Cites: 9 (see at Google Scholar)

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FastM: Design and Evaluation of a Fast Mobility Mechanism for Wireless Mesh Networks

Abstract

Although there is a large volume of work in the literature in terms of mobility approaches for Wireless Mesh Networks, usually these approaches introduce high latency in the handover process and do not support realtime services and applications. Moreover, mobility is decoupled from routing, which leads to inefficiency to both mobility and routing approaches with respect to mobility. In this paper we present a new extension to proactive routing protocols using a fast mobility extension, FastM, with the purpose of increasing handover performance in Wireless Mesh Networks. With this new extension, a new concept is created to integrate information between neighbor wireless mesh routers, managing locations of clients associated to wireless mesh routers in a certain neighborhood, and avoiding packet loss during handover. The proposed mobility approach is able to optimize the handover process without imposing any modifications to the current IEE 802.11 MAC protocol and use unmodified clients. Results show the improved efficiency of the proposed scheme: metrics such as disconnection time, throughput, packet loss and control overhead are largely improved when compared to previous approaches. Moreover, these conclusions apply to mobility scenarios, although mobility decreases the performance of the handover approach, as expected.

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2008

An Architecture For Community Mesh Networking

Abstract

The advances on wireless mesh networks are shifting the communications paradigm, where users can benefit from their cooperation to exchange information and make use of the spectrum space, forming wireless neighbourhood communities where resources are shared and services are distributed. This paper presents a modular cross-layer community management architecture, which considers that communities are formed and managed at different layers, from physical to application. It focus in more depth on one of its modules, implementing a community discovery mechanism designed to work in wireless mesh networks, and able to perform community advertisement and discovery with low overhead and delay, as compared to current approaches.

Cites: 5 (see at Google Scholar)

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Managing Community-aware Wireless Mesh Networks

Abstract

Wireless Mesh Networks, due to their typical architecture and deployment, are able to respond to user expectations as no other technology allows. Its typical multi-level approach facilitates local interactions by nearby wireless nodes from multiple users. Also, adaptation to user expectations on a dynamic manner is able to of further enhancing the capacity of these networks, while increasing its ubiquity. Nevertheless, these networks have no management model. In the paper we present the foundations for a management model for community aware networking. Design challenges for community management are identified and a management framework supporting the relevant concepts, linking social aspects and technology, is described.

Cites: 3 (see at Google Scholar)

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Fast mobility in proactive routing protocols

Abstract

This paper presents an innovative extension to routing protocols using a back-tracing technique to improve performance of handovers in wireless mesh networks. The main purpose of this extension is to minimize disconnection time and packets losses when mobility occurs. The proposed scheme requires some minor changes to the original proactive ad-hoc routing protocol, but does not impose any modification to the current IEE 802.11 MAC protocol. Some additional changes are also required to the handover signalling, in order to better optimize the process. The back-tracing mechanism is also able to reach route convergence to a minimum route length maintaining the throughput of data packets. The results of the proposed extension show that it is able to maintain the network throughput in wireless mesh networks during mobility, minimizing the packet losses.

Cites: 3 (see at Google Scholar)

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Ontology-driven Framework for Community Networking Management

Abstract

Wireless technologies present many benefits when used to deploy metropolitan networks. Resilience, cost, adaptability and self-organization are some of the benefits provided by Wireless Networks. Especially when mesh technologies are used, wireless networks are adequate for the deployment of (user-centric) community networks. The increased participation of users and the social relations existing among them makes desirable the merging of the mesh and social aspect of these networks. If proper interfaces are deployed, users are able to map existing (or to be developed) social structures such as communities into the mesh network. This paper focuses on the problem of creating a community driven mesh network, and in the representation and maintenance of user relations, trust and functional parameters. We present a novel ontology designed for the management of such environments.

Cites: 2 (see at Google Scholar)

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Community Building over Neighborhood Wireless Mesh Networks

Abstract

The fourth generation (4G) network paradigm has long been sought. A user-centric vision for such "always best connected" next-generation 4G networks is neighborhood wireless mesh networks (WMNs). In this context, the vision for the formation of WMNs reflects the trade-off between the immediate self-interest of the user, and the user's need for social contacts. Notably, users would be required to pool their resources in order to support the creation and operation of the underlying communication network (participating at all physical, access, and network layers), but also for the service provision on top of it. We argue that the design of communities suitable for this environment will encourage users to participate, enable trustworthy network creation, and provide a social layer, which can be exploited in order to design cross-layer incentive mechanisms that will further encourage users to share their resources and cooperate at lower layers.

Cites: 63 (see at Google Scholar)

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2007

On The Limits of Ad-hoc Networks - Experimental Evaluation

Abstract

This paper presents an experimental evaluation of a multi-service Ad-hoc network architecture, interconnected with a fixed network. This network supports the efficient delivery of services, unicast and multicast, legacy and multimedia, to users connected in the ad-hoc network. It contains the support for routing with delivery of multicast services, mobility, QoS mechanisms to support service differentiation and resource control responsive to node mobility as well as security, charging and rewarding mechanisms to ensure the correct behaviour of the users in the ad-hoc network. This paper experimentally evaluates the performance of the proposed mechanisms, and the influence and performance penalty introduced in the network, with the incremental inclusion of new functionalities. Results, although biased by the software implementations, may question the usage of ad-hoc networks for more than a minimal number of hops.

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Role Based Cross-Layer Communities in WMN

Abstract

The community notion can be exploited as a rational concept leading users to cooperate in sharing resourceson Wireless Mesh Networks. We propose a novel concept for self-organizing networks, where multipleentities (network elements or users) collaborate to achieve common goals, and in particular, to establish thebasic connectivity and service delivery infrastructures. The resulting architecture is based on wireless meshcommunications, with different entities taking different roles in the communities in a cross-layer approach.These communities can collaborate, leading to increasingly complex and geographically extended scenarios.

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Experimental Evaluation of the Usage of Ad Hoc Networks as Stubs for Multiservice Networks

Abstract

This paper describes an experimental evaluation of a multiservice ad hoc network, aimed to be interconnected with an infras- tructure, operator-managed network. This network supports the efficient delivery of services, unicast and multicast, legacy and multimedia, to users connected in the ad hoc network. It contains the following functionalities: routing and delivery of unicast and multicast services; distributed QoS mechanisms to support service differentiation and resource control responsive to node mobility; security, charging, and rewarding mechanisms to ensure the correct behaviour of the users in the ad hoc network. This paper experimentally evaluates the performance of multiple mechanisms, and the influence and performance penalty introduced in the network, with the incremental inclusion of new functionalities. The performance results obtained in the different real sce- narios may question the real usage of ad-hoc networks for more than a minimal number of hops with such a large number of functionalities deployed.

Cites: 7 (see at Google Scholar)

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2006

Mechanisms for Secure Charging in Self-Organised Networks

Abstract

Self-organised and ad-hoc networks are an area with an existing large research community. These networks are much useful in scenarios requiring a rapidly deployed, low cost and highly adaptable network. Recently, infrastructure networks, which are managed in a much centralised form, are starting to introduce concepts of self-organised networks in its architecture. In opposition to centralised systems, self-organisation creates the necessity for all nodes to behave according to the best interest of the network. The fact that in many ad-hoc networks nodes have scarce resources poses some threats to this requirement. As resources decreases, such as battery or wireless bandwidth, nodes can start acting selfishly. This behaviour is known to bring damage to self-organised networks and threatens the entire network. Several proposals were made in order to promote the correct usage of the network. Some proposals are based on local information and direct credit exchange while others envision the existence of a central bank. The later solutions are further elaborated in this thesis, as they make possible integration of ad-hoc network with operator driven infrastructures. This work presents the current state-of-the-art on the area providing a detailed insight on the methods adopted by each solution presented. Two novel solutions are proposed providing charging support for integrated ad-hoc networks. Both solutions provide means of integration with standard management methods found in operator networks. Also, node's motivation is increased through the reward of nodes forwarding data packets. The entire process is cryptographically secure, making use of standard methods such as Elliptic Curve DSA and strong digest functions. The solutions proposed are described and analysed analytically, comparing the results with other state-of-the-art proposals. Extensive simulation work is also presented which furthers evaluates the solutions in complex scenarios. Results are obtained from these scenarios and several metrics are evaluated taking in consideration mobility, network load, routing protocol and transport protocol. The architecture and results obtained with a real implementation are finally presented and analysed.

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Experimental Evaluation of an Integrated Ad-Hoc Network

Abstract

This paper presents an experimental evaluation of an Ad-hoc network architecture integrated with the infrastructure network, developed in the framework of the IST Daidalos project. This architecture supports the efficient delivery of services, unicast and multicast, legacy and multimedia, to users connected to the ad-hoc network. It contains functionalities of routing and mobility to enable mobility of users inside and between ad-hoc networks, distributed QoS mechanisms to support service differentiation and resources control responsive to nodes mobility, and security, charging and rewarding mechanisms to ensure the correct behaviour of the users in the ad-hoc network. This paper experimentally evaluates the performance of the proposed mechanisms, and the influence and performance penalty introduced in the architecture, with the incremental inclusion of the proposed mechanisms.

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2005

Evaluation of MANET Charging Protocols in Hotspot Scenarios

Abstract

This document compares several proposals for charging and rewarding mechanisms in ad-hoc networks, in terms of its real-time charging efficiency and impact on the overall network throughput. We notice that the introduction of charging and rewarding mechanisms in the ad-hoc network may have impact on the network performance, and then these proposals must be carefully chosen.

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The Polynomial-Assisted Ad Hoc Charging Protocol

Abstract

The area of trustworthy charging in self-organized environments has been developed quite recently. This paper introduces a new secure charging-protocol, the polynomial-assisted charging protocol, for these environments. The protocol relies on polynomial composition for speeding the identification process in small groups. This protocol is able to provide strict guarantees of cooperative behavior in traffic forwarding, with minimal network overhead. Protocol performance is evaluated in multiple ad-hoc environments and results are compared with previously proposed work. The performance results show the merits of this protocol in multiple types of environments.

Cites: 8 (see at Google Scholar)

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Mobile Ad-Hoc Networks Integration in the Daidalos Architecture

Abstract

This paper describes the Ad-hoc network integration architecture being developed inside the IST project Daidalos. This architecture contains the required functionalities to support efficient delivery of services, unicast and multicast, legacy and multimedia, to users connected to the ad-hoc network. For this purpose, several functionalities need to be in place. First, efficient routing and mobility mechanisms are proposed to decrease the overhead in the ad-hoc network. Second, distributed QoS mechanisms need to be developed to support service differentiation and resources control responsive to nodes mobility. Finally, security, charging and rewarding mechanisms are proposed to guarantee that only authorized users access the requested services, to increase the operators interest, and to ensure the correct behaviour of the users in the ad-hoc network.

Cites: 10 (see at Google Scholar)

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A Lightweight and Secure Session-Aware Ad-Hoc Charging Protocol

Abstract

Ad-hoc networks can be used to increase the radio range of hotspot scenarios and the number of prospective clients. However, the constraints created by the nature of wireless links and low power devices pose many challenges to this integration. Charging and efficient forwarding are two key functionalities in an ad-hoc network in order to allow its integration in the existing infrastructure networks. This paper proposes a lightweight and secure Session-Aware charging protocol (SACP) for these environments. This protocol is able to provide guarantees of cooperative behavior in traffic forwarding, with minimal network overhead. The performance results, evaluated in multiple environments, show the protocol merits in terms of throughput and network overhead.

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Linking Ad Hoc Charging Schemes to AAAC Architectures

Abstract

The current state of todays networks allows us to take one step further in merging the research communitys work with every days life. Wireless ad hoc networks are already well developed for specific scenarios. This work shows how to build the link between the wired network and a wireless ad hoc infrastructure, in particular routing and AAAC aspects. Such integration might lead, for example, to a better spacial and resource distributed hotspot solution. We provide the basis for inter-operation of AAAC protocols known for the fixed network, with the accounting protocol that performs the accounting and charging functions in the ad hoc network. This paper further describes the implementation of the Secured Charging Protocol as an instantiation of a charging protocol for ad hoc networks and the features which were added to improve the interface to an external accounting system. It covers the interaction with the MANET routing protocol and how to deal with routes to or from outside the ad hoc cloud.

Cites: 3 (see at Google Scholar)

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2004

Implementing Charging in Mobile Ad-hoc Networks

Abstract

In order to keep up with new networking needs, it becomes necessary to adopt mechanisms for charging network usage in a universal way. The Secure Charging Protocol (SCP) aims at answering this complex authentication, authorization, accounting and charging (AAAC) problem, and provides a view based on a different business model, one that has been adjusted to cope with technological changes. This document discusses SCP as a possible solution to the AAAC problems in MANETs and addresses the improvements made to this protocol in terms of Quality of Service (QoS) and User Interfaces. An implementation of this protocol on PDAs is also described.

Cites: 3 (see at Google Scholar)

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On the limitations of security concepts for mobile adhoc networks routing protocols

QoS-differentiated secure charging in ad-hoc environments

Abstract

In order to keep up with new networking needs, it is necessary to adopt mechanisms for charging network usage in a universal way. The Secure Charging Protocol (SCP) aims at answering this complex authentication, authorization, accounting and charging (AAAC) problem. SCP fits business models especially adequate for ad-hoc networks. This document discusses SCP as a possible solution to the AAAC problems in MANETs and presents the improvements made to this protocol in terms of Quality of Service (QoS). An implementation of this protocol on PDAs and the results achieved are discussed.

Cites: 4 (see at Google Scholar)

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2003

Síntese e Implementação de Circuitos Digitais Reconfiguráveis Dinamicamente (Projecto 4)

Abstract

The paper presents the results of the project proposed to the authors (who are the 4th year students of LECT) and shows how the specified problem has been solved. The description of the project and the basic requirements have been considered in the papers [1,2].

System to Support the Organization and Management of Scientific Conferences (CoW - Conference on the Web)

Abstract

This article presents a software package developed to help in the organization and management of Scientific Conferences on the Web (CoW). This software was developed by students of the last year of the Computers and Telematics Engeneering Degree in the aim of the Multimedia Tools and Applications 5th year optional discipline.

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S\'\intese e Implementa\cc\~ao de Circuitos Digitais Recinfigur\'aveis Dinamicamente (Projecto 4)

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