SDN/NFV-enabled satellite communications networks: opportunities, scenarios and challenges

In the context of next generation 5G networks, the satellite industry is clearly committed to revisit and revamp the role of satellite communications. As major drivers in the evolution of (terrestrial) fixed and mobile networks, Software Defined Networking (SDN) and Network Function Virtualisation (NFV) technologies are also being positioned as central technology enablers towards improved and more flexible integration of satellite and terrestrial segments, providing satellite network further service innovation and business agility by advanced network resources management techniques. Through the analysis of scenarios and use cases, this paper provides a description of the benefits that SDN/NFV technologies can bring into satellite communications towards 5G. Three scenarios are presented and analysed to delineate different potential improvement areas pursued through the introduction of SDN/NFV technologies in the satellite ground segment domain. Within each scenario, a number of use cases are developed to gain further insight into specific capabilities and to identify the technical challenges stemming from them.Peer ReviewedPostprint (author's final draft

A cloud-enabled small cell architecture in 5G networks for broadcast/multicast services

© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The evolution of 5G suggests that communication networks become sufficiently flexible to handle a wide variety of network services from various domains. The virtualization of small cells as envisaged by 5G, allows enhanced mobile edge computing capabilities, thus enabling network service deployment and management near the end user. This paper presents a cloud-enabled small cell architecture for 5G networks developed within the 5G-ESSENCE project. This paper also presents the conformity of the proposed architecture to the evolving 5G radio resource management architecture. Furthermore, it examines the inclusion of an edge enabler to support a variety of virtual network functions in 5G networks. Next, the improvement of specific key performance indicators in a public safety use case is evaluated. Finally, the performance of a 5G enabled evolved multimedia broadcast multicast services service is evaluated.Peer ReviewedPostprint (author's final draft

Thinking vulnerability infrastructurally: Interdependence and possibility in Lebanon’s overlapping crises

The notion of ‘vulnerability’ has gained growing traction in a range of different fields, from disaster risk reduction to feminist theory. This increased academic use has been paralleled by a rise in the use of the term as an operational concept in humanitarian and development policy. Using the incongruent deployments of the term as a starting point, this article examines the assumptions underpinning definitions of vulnerability in humanitarian programming in Lebanon, with a particular focus on the links between Lebanon’s crisis of public services and the mass displacement from neighbouring Syria since 2011. We show that, in the international response to Lebanon’s overlapping crises, ‘vulnerability’ is operationalised in ways that fail to address underlying causes, and thus resist meaningful transformation while even bearing the potential of additional harm. Based on the finding that vulnerabilities emanating from Lebanon’s public service crisis and from mass displacement are deeply entangled, the article proposes that an ‘infrastructural’ approach to vulnerability may better be able to address precariousness and precarity linked to basic service provision. An infrastructural approach, we posit, foregrounds dynamic interdependency and relationality with the human and non-human environment. Such a view allows us to acknowledge the power relations at work in both the production and alleviation of vulnerability and ultimately may better enable us to ‘think otherwise’ in situations of seemingly perpetual crisis and disruption

Algorithms for advance bandwidth reservation in media production networks

Media production generally requires many geographically distributed actors (e.g., production houses, broadcasters, advertisers) to exchange huge amounts of raw video and audio data. Traditional distribution techniques, such as dedicated point-to-point optical links, are highly inefficient in terms of installation time and cost. To improve efficiency, shared media production networks that connect all involved actors over a large geographical area, are currently being deployed. The traffic in such networks is often predictable, as the timing and bandwidth requirements of data transfers are generally known hours or even days in advance. As such, the use of advance bandwidth reservation (AR) can greatly increase resource utilization and cost efficiency. In this paper, we propose an Integer Linear Programming formulation of the bandwidth scheduling problem, which takes into account the specific characteristics of media production networks, is presented. Two novel optimization algorithms based on this model are thoroughly evaluated and compared by means of in-depth simulation results

Dynamics and challenges of microgrids implementation

Thesis (S.M.)--Massachusetts Institute of Technology, Sloan School of Management, 2013.Cataloged from PDF version of thesis.Includes bibliographical references (p. 64-69).Microgrids have the capability of operating on an island mode as well as an integrated mode with the smart grid, depending on the requirement and objectives. Recently, microgrids projects have gained popularity both in developed world and developing world because of their ability to lower cost, increase resiliency and overall power quality. However, most of the studies on microgrids till now have focused on the technological challenges associated with design and implementation of microgrids. This study tries to develop an industry perspective on the recent development of microgrids. Several case studies from both developed world and developing world are explained to understand drivers, constraints and challenges of microgrid implementation. A generic model used by Weil and Utterback (2005) forms the basis for this study to develop a conceptual model, mapping different social, technological, market and regulatory factors which influence technology and industry evolution. The same model is used to develop a scenario analysis to predict future development of microgrids as a technology and as an industry.by Vikalp Pal Sabhlok.S.M

A social cost benefit analysis of grid-scale electrical energy storage projects: a case study

This study explores and quantifies the social costs and benefits of grid-scale electrical energy storage (EES) projects in Great Britain. The case study for this paper is the Smarter Network Storage project, a 6 MW/10MWh lithium battery placed at the Leighton Buzzard Primary substation to meet growing local peak demand requirements. This study analyses both the locational and system-wide benefits to grid-scale EES, determines the realistic combination of those social benefits, and juxtaposes them against the social costs across the useful lifecycle of the battery to determine the techno-economic performance. Risk and uncertainty from the benefit streams, cost elements, battery lifespan, and discount rate are incorporated into a Monte Carlo simulation. Using this framework, society can be guided to cost-effectively invest in EES as a grid modernization asset to facilitate the transition to a reliable, affordable, and clean power system