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

On the virtualization and dynamic orchestration of satellite communication services

Key features of satellite communications such as wide-scale coverage, broadcast/multicast support and high availability, together with significant amounts of new satellite capacity coming online, anticipate new opportunities for satellite communications services as an integral part within upcoming 5G systems. To materialize these opportunities, satellite communications services have to be provisioned and operated in a more flexible, agile and cost-effective manner than done today. In this context, this paper describes a solution for the virtualization and dynamic orchestration of satellite communication services that builds on the introduction of Software Defined Networking (SDN) and Network Function Virtualization (NFV) technologies within the satellite ground segment systems. Along with the description of the main system architecture traits, the flowchart of a general procedure for the dynamic instantiation of virtualized satellite networks on top of a SDN/NFV-enabled satellite ground segment system is provided. The paper also presents experimental results for the dynamic customization of satellite network services through the implementation of a set of virtualized satellite network functions that can be orchestrated over general purpose open virtual platforms.Peer ReviewedPostprint (author's final draft

Enhancing satellite & terrestrial networks integration through NFV/SDN technologies

NFV and SDN technologies can become key facilitators for the combination of terrestrial and satellite networks. Enabling NFV into the SatCom domain will provide operators with appropriate tools and interfaces in order to establish end-to-end fully operable virtualized satellite networks to be offered to third-party operators/service providers. Enabling SDNbased, federated resource management paves way for a unified control plane that would allow operators to efficiently manage and optimize the operation of the hybrid network. The proposed solution is expected to bring improved coverage, optimized communication resources use and better network resilience, along with improved innovation capacity and business agility for deploying communications services over combined networks.Postprint (author's final draft

Satellite gateway diversity in SDN/NFV-enabled satellite ground segment systems

© 2017 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.This paper explores how to use Software Defined Networking (SDN) and Network Functions Virtualization (NFV) as two emerging technologies to support Satellite Gateway Diversity (GWD) solution in the forward link to provide next generation satellite system with higher capacity enhancement, failover and resiliency management. In this context, the gateway handover along with efficient traffic steering techniques are used to cope with the cases where gateway feeder links experience outage due to meteorological conditions or gateway failure. The handover typically implies that additional traffic is addressed towards another satellite gateway to handle the capacity reduction. Toward this objective, we propose an architecture framework to support GWD using SDN/NFV-enabled satellite ground segment and we evaluate our solution on a proof of concept experimental testbed based on OpenSAND emulated satellite network. The results show that our proposal can provide reasonably flexibility to handle failover and resiliency.Peer ReviewedPostprint (author's final draft

Software-defined satellite cloud RAN

This paper provides a feasibility study on the virtualization of a DVB-S2/DVB-RCS2 satellite ground infrastructure and its SDN-based management and control. The proposed framework, SatCloudRAN, is expected to increase the opportunities of smoothly integrating the satellite components in forthcoming 5G systems. We analyze the design of SatCloudRAN by considering various chaining of virtual and physical functions and the characteristics of the links between them. We based our analysis on a generic architecture of bidirectional access networks that follows the normative documents of the broadband forum and leverage virtualization and softwarization technologies, namely NFV and SDN, to achieve a flexible and programmable control and management of satellite infrastructure. Using a SatCloudRAN approach, network operators will be able to provide: (1) optimized dynamic QoS, (2) resilient management of multiple satellite gateways, and (3) dynamic bandwidth on demand. Copyright c 2016 John Wiley & Sons, Ltd

Software-defined satellite cloud RAN

This is the peer reviewed version of the following article: Ahmed, T., Dubois, E., Dupé, J.-B., Ferrús, R., Gélard, P., and Kuhn, N. (2018) Software-defined satellite cloud RAN. Int. J. Satell. Commun. Network., 36: 108–133, which has been published in final form at 10.1002/sat.1206. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.This paper provides an assessment study on the virtualization of a Digital Video Broadcasting - Satellite - Second Generation (DVB-S2)/ Digital Video Broadcasting - Return Channel Satellite - Second Generation (DVB-RCS2) satellite ground infrastructure and proposes a framework, named Satellite Cloud Radio Access Network (SatCloudRAN), that aims to ease the integration of satellite components in forthcoming 5G systems. Special attention is given to the design of SatCloudRAN by considering the split and placement of virtualized and nonvirtualized functions while taking into account the characteristics of the transport links connecting both type of functions. We assess how virtualization and softwarization technologies, namely, network function virtualization and software-defined networking, can deliver part of the satellite gateway functionalities as virtual network functions and achieve a flexible and programmable control and management of satellite infrastructure. Under the network function virtualization paradigm, building virtual network function blocks that compose a satellite gateway have been identified, and their interaction exhibited. This paper also gives insights on how the SatCloudRAN approach can allow operators to provide software-defined networking-based (1) bandwidth on demand, (2) dynamic Quality of Service, and (3) satellite gateway diversity.Peer ReviewedPreprin

Functional Simulation of the Uses of the Onboard Inter-Satellite Network in a Swarm

There are several network simulators (some on the shelves) that are very useful and helpful for network engineering. Nevertheless, none is efficient enough for simulating an onboard network spread among spacecrafts that are moving in space according to Kepler laws. Therefore, we tried to fill this gap by building our own tool based on the CNES expertise in space simulator benches. Our bench simulates the environment and the dynamics of each spacecraft, provides a model of the physical layer of the network layer (i.e. Radio Frequency transmission between moving vehicles) and offers an interface to run actual Flight Software. Embedding flight software allows us to perform functional demonstration of the network use at system level. As a first step, in order to characterize the network, we have implemented a routing policy based on the flooding principle

(Post-)queer citizenship in contemporary republican France

1996 saw the publication of Frédéric Martel’s Le Rose et le noir, a comprehensive study of three decades of gay life in metropolitan France. The predominantly anti-communitarian stance adopted by Martel in the epilogue to the first edition of his work had evolved, by the time of the book’s publication en poche in 2000, into a more nuanced view of the interactions and intersections between queer and republican identities in contemporary France. This development was influenced, in large part, by concrete changes which took place over the second half of the 1990s, centring around the introduction of the PACS in 1999, and leading to an ever-broadening debate. This paper will begin by setting forth the ways in which Martel’s position changed and analysing the attitudinal, social, and legislative backdrop which paved the way for such a change to occur. It will then bring Martel’s work into a dialogue with the writings of Eric Fassin and Maxime Foerster, both of whom have, like Martel, offered crucial analyses of the place of queer citizens within the contemporary French republic. Particular attention will first be paid to the ways in which Fassin, in his writings, has underlined the salience of the ‘droit du sol/droit du sang’ debate, traditionally associated with questions of ethnic belonging, in light of public and political discussions revolving around questions of queer kinship raised by the introduction of the PACS. This will lead into an examination of Foerster’s assertion that gay citizens of the Republic, in the era of the PACS, find themselves in a role previously held by women, in other words, as elements that require integration within a republican model. Foerster argues that this requirement to integrate is indicative of the fact that the traditional republican claim that the citizen is a blank canvas is at best misguided, and, at worst, has been deliberately subverted. This paper will examine the manner in which Martel and Fassin’s observations can be used to further strengthen the points raised by Foerster, concluding with the latter that a true engagement with the issues raised by debates around queer citizenship over the past decade can, in fact, allow the contemporary republican citizen to ‘devenir ceux [qu’il] est’. In other words, the article will conclude that the potential impact of the PACS legislation and the broader discussions it has provoked could be a renegotiation of the relationship between queer citizens and the republic

Gateway selection optimization in Hybrid MANET-Satellite network

International audienceIn this paper, we study the problem of gateway placement in an hybrid mobile ad hoc - satellite network. We propose a genetic algorithms approach to solve this multi-criteria optimization problem. The analysis of the proposed algorithm is made by means of simulations. Topology dynamics are also taken into account since the node mobility will impact the gateway placement decisions. Our solution shows promising results and displays unmatched flexibility with respect to the optimization criteria

Traffic contracts based optimizations for QoS support in DVB-RCS satellite systems

International audienceThe Return Channel for Satellite (DVB-RCS) standard has become a mature technology for Internet communications via satellite access networks. Because of the propagation delay, as well as the expensive and scarce resources, the QoS support has to be optimized and harmonized. Indeed, it is provided at different independent layers (mainly layer 2,3 and application level) which are potentially either redundant or inconsistent. This paper suggests optimizations (between layer 2 and 3) for the resource sharing based on traffic contracts and using cross layer mechanisms. The traffic contracts are mainly used to perform a prediction of the incoming traffic evolution in order to reduce the effects of the transmission delay. In addition, a way to coordinate layer 2 and 3 schedulers is introduced. A first performance assessment of the proposed mechanisms in a DVB-RCS context shows that the layer 3 delays (introduced by queuing) are significantly reduced