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The pioneering 5G Smart Tourism (5GST) project demonstrates how the cultural, heritage and tourism sectors can create interactive immersive experiences in a way never seen before; from an augmented reality tour of the 2000 year old Roman... more
The pioneering 5G Smart Tourism (5GST) project demonstrates how the cultural, heritage and tourism sectors can create interactive immersive experiences in a way never seen before; from an augmented reality tour of the 2000 year old Roman Baths, to 360 degree immersive experiences, and an entirely new way of looking at art, all enabled by 5G. This paper presents the key technical findings from the public trials of several 5GST use cases. These findings explain how Multi-Access Edge Computing (MEC) infrastructure is utilized to run compute workloads closer to the end user, therefore reducing end-to-end latency and thus improving quality of user experience. Finally, this paper discusses how 5G will transform the business models for delivering such 5G-enabled services.
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Opportunistic mobile networks have attracted a lot of attention and several routing protocols have been proposed. However, most algorithms do not consider the importance of users' properties of human mobility in physical world. Given... more
Opportunistic mobile networks have attracted a lot of attention and several routing protocols have been proposed. However, most algorithms do not consider the importance of users' properties of human mobility in physical world. Given this fact, in this work we enhance CLWPR, a cross-layer optimized position-based routing protocol for urban VANET environments, combining social properties and users' individual mobility traces in order to design an efficient content dissemination scheme. We introduce an offline social metric (OSM), which is based on physical proximity and opportunistic contacts of nodes. Our proposed protocol favors nodes with close offline social relationship as next forwarder nodes. We present a comprehensive study of the performance of our enhanced CLWPR protocol routing against other routing protocols in distributed vehicular networks using realistic representative urban scenarios with synthetic and real traffic.
Recentadvances inmobilecommunications and computing andstrong interest ofthescientific community in theGridhaveledtoresearch intotheMobile Grid. We discuss various approaches proposed intheliterature andtrytopoint outthefundamental issues... more
Recentadvances inmobilecommunications and computing andstrong interest ofthescientific community in theGridhaveledtoresearch intotheMobile Grid. We discuss various approaches proposed intheliterature andtrytopoint outthefundamental issues andproblems emerging fromthe introduction ofmobiledevices andwireless communications inthecontext oftheGridcomputing paradigm. We further propose anarchitecture fortherealization ofa MobileGrid andinvestigate keydesign decisions andoptimizations.
Research Interests: Computer Science and Grid
Research Interests: Computer Science and Acm
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Grid computing has emerged as a paradigm for coordinated resource sharing and problem solving in dynamic, multiinstitutional virtual organizations (Foster, 2001). A grid computing system is essentially a large-scale distributed system... more
Grid computing has emerged as a paradigm for coordinated resource sharing and problem solving in dynamic, multiinstitutional virtual organizations (Foster, 2001). A grid computing system is essentially a large-scale distributed system designed to aggregate resources from multiple sites, giving to users the opportunity to take advantage of enormous computational, storage, or bandwidth resources that would otherwise be impossible to attain. Current applications of grid computing focus on computational-expensive processing of large volumes of scientific data, for example, for earthquake simulation, signal processing, cancer research, and pattern search in DNA sequences. At the same time, the recent advances in mobile and wireless communications have resulted in the availability of an enormous number of mobile computing devices such as laptop PCs and PDAs (personal digital assistants). Thus, it is natural to extend the idea of resource sharing to mobile and wireless computing environmen...
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It has long been realized that the proliferation of information-centric applications and services must be reflected in a corresponding shift of the underlying Internet architecture. Even though users increasingly focus on the desired... more
It has long been realized that the proliferation of information-centric applications and services must be reflected in a corresponding shift of the underlying Internet architecture. Even though users increasingly focus on the desired information, the underlying network still focuses on the endpoints providing/consuming this information and in many cases this mismatch has resulted in an inefficient utilization of network resources, as demonstrated by peer-to-peer (P2P) and file sharing applications. In view of this situation, ...
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Abstract: This paper shows how the multicast nature of proposed future publish/subscribe network architectures can assist mobility. Publish/subscribe is an information-centric networking paradigm. Unlike the current send/receive based... more
Abstract: This paper shows how the multicast nature of proposed future publish/subscribe network architectures can assist mobility. Publish/subscribe is an information-centric networking paradigm. Unlike the current send/receive based Internet architecture which which favours the sender of information, the publish/subscribe paradigm leads to a more balanced relationship between entities. Publish/subscribe is considered a promising architecture for the future Internet as it can potentially address various current Internet ...
Research Interests: Computer Science, Distributed Denial of Service Attack, Future Internet, Mobility Management, Computer Network, and 10 moreMulticast, Real Time, Network Architecture, Publish/subscribe, Denial of Service, Mobile Tv, Multimedia Application, Overlay Multicast, Continuous Media, and Distributed Denial of Service
Recent advances in mobile communications and computing and strong interest of the scientific community in the grid have led to research into the mobile grid. Based on a realistic mobile grid architecture we formulate the problem of job... more
Recent advances in mobile communications and computing and strong interest of the scientific community in the grid have led to research into the mobile grid. Based on a realistic mobile grid architecture we formulate the problem of job scheduling in a mobile environment and investigate key design decisions with respect to fundamental performance metrics. We extend previous work by introducing a new scheduling policy based on the notion of installments and continue the evaluation of the expanded set of scheduling ...
Research Interests: Computer Science, Computer Architecture, Distributed Computing, Grid Computing, Environmental Economics, and 10 moreScheduling, Mobile Communication, Mobile Computing, Business Communication, Performance Evaluation, Scientific Communication, Job Scheduling, Replication, Grid System, and Mobile Environment
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Future wireless local area networks (WLANs) are expected to serve thousands of users in diverse environments. To address the new challenges that WLANs will face, and to overcome the limitations that previous IEEE standards introduced, a... more
Future wireless local area networks (WLANs) are expected to serve thousands of users in diverse environments. To address the new challenges that WLANs will face, and to overcome the limitations that previous IEEE standards introduced, a new IEEE 802.11 amendment is under development. IEEE 802.11ax aims to enhance spectrum efficiency in a dense deployment; hence system throughput improves. Dynamic Sensitivity Control (DSC) and BSS Color are the main schemes under consideration in IEEE 802.11ax for improving spectrum efficiency In this paper, we evaluate DSC and BSS Color schemes when physical layer capture (PLC) is modelled. PLC refers to the case that a receiver successfully decodes the stronger frame when collision occurs. It is shown, that PLC could potentially lead to fairness issues and higher throughput in specific cases. We study PLC in a small and large scale scenario, and show that PLC could also improve fairness in specific scenarios.
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This deliverable describes the implementation framework, the workflows for development, and the security coding guidelines that the development tasks have to follow in order to ease the continuous integration of the prototype.
The first wave of IEEE 802.11ax capable devices have already hit the market, aiming at enhancing the Quality of Experience (QoE) for the users in dense deployments, by enabling novel features to improve throughput and spectrum efficiency.... more
The first wave of IEEE 802.11ax capable devices have already hit the market, aiming at enhancing the Quality of Experience (QoE) for the users in dense deployments, by enabling novel features to improve throughput and spectrum efficiency. One of these features is Spatial Reuse (SR) mechanism, which is introduced for coping with the exposed node problem. Under the SR operation, nodes belonging on different Basic Service Sets (BSSs) are allowed to initiate concurrent transmissions, utilising the spectrum resources and improving throughput. However, the main challenge for this enabling technology is the increased interference level that is introduced by the concurrent transmissions. Even though, there are a few algorithms available in the literature that study this issue for the IEEE 802.11ax, in this article we look into that issue from a different perspective. We propose an Interference-Aware scheduler for the Medium Access Control (MAC) queue based on the interference level observed...
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CARMA (Cloud-Assisted Real-time Methods for Autonomy) is a highly innovative and challenging project which aims to develop and test cooperative automated driving technology, based on a distributed control system. The approach is enabled... more
CARMA (Cloud-Assisted Real-time Methods for Autonomy) is a highly innovative and challenging project which aims to develop and test cooperative automated driving technology, based on a distributed control system. The approach is enabled by an ultra-low latency and highly reliable cloud-based infrastructure accessed through 5G. This paper describes the 3-tier distributed computing architecture used in the project comprising the Vehicle, the Edge cloud and the Core. It describes a methodology to test a set of use cases representative of both urban and highway driving and explores the key challenges in such an approach. The first technical challenge is the design of a mobile edge cloud infrastructure that is able to support real-time and safety critical applications. Another non-trivial problem is that of cyber-security for such a real-time cyber physical system. Progress during the first year of this five year project is described.
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The purpose of this paper is to provide a comprehensive study on routing protocols for Vehicular Ad-hoc Networks (VANETs). The characteristics of vehicular communications favour the use of position based routing. Enhancements have been... more
The purpose of this paper is to provide a comprehensive study on routing protocols for Vehicular Ad-hoc Networks (VANETs). The characteristics of vehicular communications favour the use of position based routing. Enhancements have been proposed in order to use additional information such as navigation information in the routing decisions to further improve the performance of these protocols. However, positionbased routing is faced with the local-maximum problem for which recovery policies have been proposed. The carry-n-forward mechanism is the most suitable for VANETs when end-to-end delay limits are not strict. Moreover, the requirements for Quality of Service (QoS) impose new challenges in routing which are not feasible to be solved using single layer information. Therefore, cross-layer approaches have been proposed to take into account the link or path quality using information from MAC and physical layer. Finally, every position-based routing protocol needs to know the position...
We identify the obstacles hindering the deployment of Information Centric Networking (ICN) and the shift from the current IP architecture. In particular, we argue that scalability of name resolution and the lack of control of content... more
We identify the obstacles hindering the deployment of Information Centric Networking (ICN) and the shift from the current IP architecture. In particular, we argue that scalability of name resolution and the lack of control of content access from content providers are two important barriers that keep ICN away from deployment. We design solutions to incentivise ICN deployment and present a new network architecture that incorporates an extra layer in the protocol stack (the Location Independent Routing Layer, LIRA) to integrate location-independent content delivery. According to our design, content names need not (and should not) be permanent, but rather should be ephemeral. Resolution of non-permanent names requires the involvement of content providers, enabling desirable features such as request logging and cache purging, while avoiding the need for the deployment of a new name resolution infrastructure. Our results show that with half of the network's nodes operating under the L...
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Network Coding is an efficient concept to improve the network capacity under lossy channels. In this paper, we present a scheme based on Serially Concatenated Code (SCC) that has been proposed in the literature and comprises an outer... more
Network Coding is an efficient concept to improve the network capacity under lossy channels. In this paper, we present a scheme based on Serially Concatenated Code (SCC) that has been proposed in the literature and comprises an outer fountain code and Random Linear Network Coding (RLNC) as an inner code to allow intermediate nodes to re-encode the information. We have placed SCC in a shim layer between the Medium Access Control (MAC) and Network layers where the (de-)coders operate. Furthermore, a header for the SCC scheme was also introduced that carries the information required for decoding the information. Simulation results in a fading IEEE 802.11 channel and an analysis based on the IEEE 802.11 basic access scheme, show that SCC can indeed improve the performance when it is carefully designed and can provide a means of enabling robust communications without the use of ACKs and retransmissions (i.e. multicast/broadcast communications).
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IEEE 802.11ax Spatial Reuse (SR) is a new category in the IEEE 802.11 family, aiming at improving the spectrum efficiency and the network performance in dense deployments. The main and perhaps the only SR technique in that amendment is... more
IEEE 802.11ax Spatial Reuse (SR) is a new category in the IEEE 802.11 family, aiming at improving the spectrum efficiency and the network performance in dense deployments. The main and perhaps the only SR technique in that amendment is the Basic Service Set (BSS) Color. It aims at increasing the number of concurrent transmissions in a specific area, based on a newly defined Overlapping BSS/Preamble-Detection (OBSS/PD) threshold and the Received Signal Strength Indication (RSSI) from Overlapping BSSs (OBSSs). In this paper, we propose a Control OBSS/PD Sensitivity Threshold (COST) algorithm for adjusting OBSS/PD threshold based on the interference level and RSSI from the associated recipient(s). In contrast to the Dynamic Sensitivity Control (DSC) algorithm that was proposed for setting OBSS/PD, COST is fully aware of any changes in OBSSs and can be applied to any IEEE 802.11ax node. Simulation results in various scenarios, show a clear performance improvement of up to 57% gain in throughput over a conservative fixed OBSS/PD for the legacy BSS Color and DSC.
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This chapter presents a thorough investigation on current vehicular networking architectures (access technologies and overlay networks) and their (r)evolution towards the 5G era. The main driving force behind vehicular networking is to... more
This chapter presents a thorough investigation on current vehicular networking architectures (access technologies and overlay networks) and their (r)evolution towards the 5G era. The main driving force behind vehicular networking is to increase safety, with several other applications exploiting this ecosystem for traffic efficiency and infotainment provision. The most prominent existing candidates for vehicular networking are based on dedicated short range communications (DSRC) and cellular (4G) communications. In addition, the maturity of cloud computing has accommodated the invasion of vehicular space with cloud-based services. Nevertheless, current architectures can not meet the latency requirements of Intelligent Transport Systems (ITS) applications in highly congested and mobile environments. The future trend of autonomous driving pushes current networking architectures further to their limits with hard real-time requirements. Vehicular networks in 5G have to address five major challenges that affect current architectures: congestion, mobility management, backhaul networking, air interface and security. As networking transforms from simple connectivity provision, to service and content provision, fog computing approaches with caching and pre-fetching improve significantly the performance of the networks. The cloudification of network resources through software defined networking (SDN)/network function virtualization (NFV) principles, is another promising enabler for efficient vehicular networking in 5G. Finally, new wireless access mechanisms combined with current DSRC and 4G will enable to bring the vehicles in the cloud.