Smart transportation systems (STSs) in critical conditions

In the context of smart transportation systems (STSs) in smart cities, the use of applications that can help in case of critical conditions is a key point. Examples of critical conditions may be natural-disaster events such as earthquakes, hurricanes, floods, and manmade ones such as terrorist attacks and toxic waste spills. Disaster events are often combined with the destruction of the local telecommunication infrastructure, if any, and this implies real problems to the rescue operations.The quick deployment of a telecommunication infrastructure is essential for emergency and safety operations as well as the rapid network reconfigurability, the availability of open source software, the efficient interoperability, and the scalability of the technological solutions. The topic is very hot and many research groups are focusing on these issues. Consequently, the deployment of a smart network is fundamental. It is needed to support both applications that can tolerate delays and applications requiring dedicated resources for real-time services such as traffic alert messages, and public safety messages. The guarantee of quality of service (QoS) for such applications is a key requirement.In this chapter we will analyze the principal issues of the networking aspects and will propose a solution mainly based on software defined networking (SDN). We will evaluate the benefit of such paradigm in the mentioned context focusing on the incremental deployment of such solution in the existing metropolitan networks and we will design a "QoS App" able to manage the quality of service on top of the SDN controller

Infrastructure sharing of 5G mobile core networks on an SDN/NFV platform

When looking towards the deployment of 5G network architectures, mobile network operators will continue to face many challenges. The number of customers is approaching maximum market penetration, the number of devices per customer is increasing, and the number of non-human operated devices estimated to approach towards the tens of billions, network operators have a formidable task ahead of them. The proliferation of cloud computing techniques has created a multitude of applications for network services deployments, and at the forefront is the adoption of Software-Defined Networking (SDN) and Network Functions Virtualisation (NFV). Mobile network operators (MNO) have the opportunity to leverage these technologies so that they can enable the delivery of traditional networking functionality in cloud environments. The benefit of this is reductions seen in the capital and operational expenditures of network infrastructure. When going for NFV, how a Virtualised Network Function (VNF) is designed, implemented, and placed over physical infrastructure can play a vital role on the performance metrics achieved by the network function. Not paying careful attention to this aspect could lead to the drastically reduced performance of network functions thus defeating the purpose of going for virtualisation solutions. The success of mobile network operators in the 5G arena will depend heavily on their ability to shift from their old operational models and embrace new technologies, design principles and innovation in both the business and technical aspects of the environment. The primary goal of this thesis is to design, implement and evaluate the viability of data centre and cloud network infrastructure sharing use case. More specifically, the core question addressed by this thesis is how virtualisation of network functions in a shared infrastructure environment can be achieved without adverse performance degradation. 5G should be operational with high penetration beyond the year 2020 with data traffic rates increasing exponentially and the number of connected devices expected to surpass tens of billions. Requirements for 5G mobile networks include higher flexibility, scalability, cost effectiveness and energy efficiency. Towards these goals, Software Defined Networking (SDN) and Network Functions Virtualisation have been adopted in recent proposals for future mobile networks architectures because they are considered critical technologies for 5G. A Shared Infrastructure Management Framework was designed and implemented for this purpose. This framework was further enhanced for performance optimisation of network functions and underlying physical infrastructure. The objective achieved was the identification of requirements for the design and development of an experimental testbed for future 5G mobile networks. This testbed deploys high performance virtualised network functions (VNFs) while catering for the infrastructure sharing use case of multiple network operators. The management and orchestration of the VNFs allow for automation, scalability, fault recovery, and security to be evaluated. The testbed developed is readily re-creatable and based on open-source software

Providing adaptive traffic routing based on user and network context

Providing real-time traffic guarantees and fairness based on the availability of network resources has been a major issue presented in the literature. However, due the convergent nature of digital architectures, the increasing demand of upcoming real-time sensitive traffic, such as VoIP, and a higher user´s adaptability (devices, global positioning, content quality, etc.), solutions based on Quality of Service (QoS) turned out to be insufficient in order to meet user´s requirements. Indeed, QoS metrics are network-centered, and mostly related to the dynamic nature of the traffic (such as throughput, delay, jitter, among others). In order to meet the need for a user-centered network, this paper proposes a context-aware solution where the concepts of Quality of Service, Quality of Experience and Adaptive Routing are integrated in order to provide a more dynamic and pro-active approach for the delivery of context-oriented time-sensitive traffic.info:eu-repo/semantics/publishedVersio

Using OSM for real-time redeployment of VNFs based on network status

Στην παρούσα διπλωματική εργασία θα εξετάσουμε την Εικονικοποίηση δικτυακών λειτουργιών (Network Functions Virtualisation - NFV) ως την κατάλληλη αρχιτεκτονική για την υλοποίηση ενός δικτύου κατάλληλου για το Διαδίκτυο των Πραγμάτων (Internet of Things - IoT), το οποίο πρέπει να είναι ευέλικτο και επεκτάσιμο. Πιο συγκεκριμένα, θα επικεντρωθούμε στην αποτελεσματική αξιοποίηση του Open Source MANO (OSM) στην υλοποίηση μιας εφαρμογής που παρακολουθεί την κατάσταση του δικτύου των Εικονικοποιημένων δικτυακών λειτουργιών (Virtual Network Functions – VNFs) και σε περίπτωση κακής κατάστασης του δικτύου (π.χ. συμφόρηση του δικτύου) αναλαμβάνει τη μετακίνηση των επηρεαζόμενων VNFs σε κάποιον άλλο Διαχειριστή Εικονικής Υποδομής (Virtual Infrastructure Manager – VIM), για να αποτραπεί η πτώση στην απόδοση των ενεργών υπηρεσιών.In this thesis we will be examining the Network Functions Virtualisation (NFV) framework as a suitable framework for implementing a network appropriate for Internet of Things (IoT), which needs to be flexible and scalable. More precisely, we will be focusing on how Open Source MANO (OSM) can be efficiently utilized in a solution that monitors the network status of Virtual Network Functions (VNFs) and in case of bad network status (e.g. network congestion) triggers the redeployment of affected VNFs to some other Virtual Infrastructure Manager (VIM) to prevent the underperformance of running services

Supporting code mobility and dynamic reconfigurations over Wireless MAC Processor Prototype

Mobile networks for Internet Access are a fundamental segment of Internet access net- works, where resource optimization are really critical because of the limited bandwidth availability. While traditionally resource optimizations have been focused on high effi- cient modulation and coding schemes, to be dynamically tuned according to the wireless channel and interference conditions, it has also been shown how medium access schemes can have a significant impact on the network performance according to the application and networking scenarios. This thesis work proposes an architectural solution for supporting Medium Access Con- trol (MAC) reconfigurations in terms of dynamic programming and code mobility. Since the MAC protocol is usually implemented in firmware/hardware (being constrained to very strict reaction times and to the rules of a specific standard), our solution is based on a different wireless card architecture, called Wireless MAC Processor (WMP), where standard protocols are replaced by standard programming interfaces. The control architecture developed in this thesis exploits this novel behavioral model of wireless cards for extending the network intelligence and enabling each node to be remotely reprogrammed by means a so called “MAC Program”, i.e. a software element that defines the description of a MAC protocol. This programmable protocol can be remotely injected and executed on running network devices allowing on-the-fly MAC reconfigurations. This work aim to obtain a formal description of the a software defined wireless network requirements and define a mechanism for a reliable MAC program code mobility throw the network elements, transparently to the upper-level and supervised by a global con- trol logic that optimizes the radio resource usage; it extends a single protocol paradigm implementation to a programmable protocol abstraction and redefines the overall wire- less network view with support for cognitive adaptation mechanisms. The envisioned solutions have been supported by real experiments running on different WMP proto- types , showing the benefits given by a medium control infrastructure which is dynamic, message-oriented and reconfigurable.Mobile networks for Internet Access are a fundamental segment of Internet access net- works, where resource optimization are really critical because of the limited bandwidth availability. While traditionally resource optimizations have been focused on high effi- cient modulation and coding schemes, to be dynamically tuned according to the wireless channel and interference conditions, it has also been shown how medium access schemes can have a significant impact on the network performance according to the application and networking scenarios. This thesis work proposes an architectural solution for supporting Medium Access Con- trol (MAC) reconfigurations in terms of dynamic programming and code mobility. Since the MAC protocol is usually implemented in firmware/hardware (being constrained to very strict reaction times and to the rules of a specific standard), our solution is based on a different wireless card architecture, called Wireless MAC Processor (WMP), where standard protocols are replaced by standard programming interfaces. The control architecture developed in this thesis exploits this novel behavioral model of wireless cards for extending the network intelligence and enabling each node to be remotely reprogrammed by means a so called “MAC Program”, i.e. a software element that defines the description of a MAC protocol. This programmable protocol can be remotely injected and executed on running network devices allowing on-the-fly MAC reconfigurations. This work aim to obtain a formal description of the a software defined wireless network requirements and define a mechanism for a reliable MAC program code mobility throw the network elements, transparently to the upper-level and supervised by a global con- trol logic that optimizes the radio resource usage; it extends a single protocol paradigm implementation to a programmable protocol abstraction and redefines the overall wire- less network view with support for cognitive adaptation mechanisms. The envisioned solutions have been supported by real experiments running on different WMP proto- types , showing the benefits given by a medium control infrastructure which is dynamic, message-oriented and reconfigurable

Topology Discovery in Autonomic Networks

The network Management Research Group (NMRG) introduced their own version of autonomic networks based on the viewpoint of the Internet Society and following the definition provided by IBM of autonomic systems. NMRG focused on self-optimizing, self-configuring, self-protecting, and self-healing capabilities in the proposed design model of autonomic networks. Later the Autonomic Networking Integrated Model and Approach (ANIMA) working group of the Internet Engineering Task Force (IETF) designed protocols to support the goals set by NMRG. The proposed autonomic network mitigates the human administration influence as much as possible and make the nodes dependent on themselves and the communications with their neighbors. Therefore, autonomic nodes will act as a network management entity that depends on the information they receive/send from/to their surroundings and their knowledge about themselves. In network management, knowing the network’s topology gives nodes a great advantage toward becoming more autonomic. Knowing the topology can help nodes with management tasks such as link failure recovery, routing, and imposing policy. Topology Discovery (TD) is the process of collecting the neighboring information of all nodes and distributing the processed information among them. Topology Maintenance (TM) takes place after the topology map is generated during the TD process. TM updates all nodes upon the changes in the topology map. The TD and TM can be heavy tasks on the network since they require collecting information from all nodes and distributing it among them. We focus on supporting the benefits of autonomic nodes knowing the network’s topology and suggest efficient methods to collect and maintain the topological information of an autonomic network. Our goal is to minimize the bandwidth consumption by reducing the number of exchanged messages for TD or TM purposes. There have been many approaches proposed to improve the performance of TD and TM. There has been thorough research on TD methodologies but not all the proposed solutions can be applied to autonomic networks. In this thesis, we review different methods for TD and discuss their compatibility with the proposed autonomic network guidelines. We then propose two new solutions. Our first solution is based on a clustering algorithm that allows the autonomic nodes to join clusters and limits the message passing to intra-cluster communications and inter-cluster communication between clusterheads. The second proposed solution is based on taking advantage of the secure boot-strapping protocol (BRSKI) for autonomic nodes to generate the topology map of the autonomic network

Flexible cross layer optimization for fixed and mobile broadband telecommunication networks and beyond

In der heutigen Zeit, in der das Internet im Allgemeinen und Telekommunikationsnetze im Speziellen kritische Infrastrukturen erreicht haben, entstehen hohe Anforderungen und neue Herausforderungen an den Datentransport in Hinsicht auf Effizienz und Flexibilität. Heutige Telekommunikationsnetze sind jedoch rigide und statisch konzipiert, was nur ein geringes Maß an Flexibilität und Anpassungsfähigkeit der Netze ermöglicht und darüber hinaus nur im begrenzten Maße die Wichtigkeit von Datenflüssen im wiederspiegelt. Diverse Lösungsansätze zum kompletten Neuentwurf als auch zum evolutionären Konzept des Internet wurden ausgearbeitet und spezifiziert, um diese neuartigen Anforderungen und Herausforderungen adäquat zu adressieren. Einer dieser Ansätze ist das Cross Layer Optimierungs-Paradigma, welches eine bisher nicht mögliche direkte Kommunikation zwischen verteilten Funktionalitäten unterschiedlichen Typs ermöglicht, um ein höheres Maß an Dienstgüte zu erlangen. Ein wesentlicher Indikator, welcher die Relevanz dieses Ansatzes unterstreicht, zeichnet sich durch die Programmierbarkeit von Netzwerkfunktionalitäten aus, welche sich aus der Evolution von heutigen hin zu zukünftigen Netzen erkennen lässt. Dieses Konzept wird als ein vielversprechender Lösungsansatz für Kontrollmechanismen von Diensten in zukünftigen Kernnetzwerken erachtet. Dennoch existiert zur Zeit der Entstehung dieser Doktorarbeit kein Ansatz zur Cross Layer Optimierung in Festnetz-und Mobilfunknetze, welcher der geforderten Effizienz und Flexibilität gerecht wird. Die übergeordnete Zielsetzung dieser Arbeit adressiert die Konzeptionierung, Entwicklung und Evaluierung eines Cross Layer Optimierungsansatzes für Telekommunikationsnetze. Einen wesentlichen Schwerpunkt dieser Arbeit stellt die Definition einer theoretischen Konzeptionierung und deren praktischer Realisierung eines Systems zur Cross Layer Optimierung für Telekommunikationsnetze dar. Die durch diese Doktorarbeit analysierten wissenschaftlichen Fragestellungen betreffen u.a. die Anwendbarkeit von Cross Layer Optimierungsansätzen auf Telekommunikationsnetzwerke; die Betrachtung neuartiger Anforderungen; existierende Konzepte, Ansätze und Lösungen; die Abdeckung neuer Funktionalitäten durch bereits existierende Lösungen; und letztendlich den erkennbaren Mehrwert des neu vorgeschlagenen Konzepts gegenüber den bestehenden Lösungen. Die wissenschaftlichen Beiträge dieser Doktorarbeit lassen sich grob durch vier Säulen skizzieren: Erstens werden der Stand der Wissenschaft und Technik analysiert und bewertet, Anforderungen erhoben und eine Lückenanalyse vorgenommen. Zweitens werden Herausforderungen, Möglichkeiten, Limitierungen und Konzeptionierungsaspekte eines Modells zur Cross Layer Optimierung analysiert und evaluiert. Drittens wird ein konzeptionelles Modell - Generic Adaptive Resource Control (GARC) - spezifiziert, als Prototyp realisiert und ausgiebig validiert. Viertens werden theoretische und praktische Beiträge dieser Doktorarbeit vertiefend analysiert und bewertet.As the telecommunication world moves towards a data-only network environment, signaling, voice and other data are similarly transported as Internet Protocol packets. New requirements, challenges and opportunities are bound to this transition and influence telecommunication architectures accordingly. In this time in which the Internet in general, and telecommunication networks in particular, have entered critical infrastructures and systems, it is of high importance to guarantee efficient and flexible data transport. A certain level of Quality-of-Service (QoS) for critical services is crucial even during overload situations in the access and core network, as these two are the bottlenecks in the network. However, the current telecommunication architecture is rigid and static, which offers very limited flexibility and adaptability. Several concepts on clean slate as well as evolutionary approaches have been proposed and defined in order to cope with these new challenges and requirements. One of these approaches is the Cross Layer Optimization paradigm. This concept omits the strict separation and isolation of the Application-, Control- and Network-Layers as it enables interaction and fosters Cross Layer Optimization among them. One indicator underlying this trend is the programmability of network functions, which emerges clearly during the telecommunication network evolution towards the Future Internet. The concept is regarded as one solution for service control in future mobile core networks. However, no standardized approach for Cross Layer signaling nor optimizations in between the individual layers have been standardized at the time this thesis was written. The main objective of this thesis is the design, implementation and evaluation of a Cross Layer Optimization concept on telecommunication networks. A major emphasis is given to the definition of a theoretical model and its practical realization through the implementation of a Cross Layer network resource optimization system for telecommunication systems. The key questions answered through this thesis are: in which way can the Cross Layer Optimization paradigm be applied on telecommunication networks; which new requirements arise; which of the required functionalities cannot be covered through existing solutions, what other conceptual approaches already exist and finally whether such a new concept is viable. The work presented in this thesis and its contributions can be summarized in four parts: First, a review of related work, a requirement analysis and a gap analysis were performed. Second, challenges, limitations, opportunities and design aspects for specifying an optimization model between application and network layer were formulated. Third, a conceptual model - Generic Adaptive Resource Control (GARC) - was specified and its prototypical implementation was realized. Fourth, the theoretical and practical thesis contributions was validated and evaluated