This dissertation aims to explore how one could leverage Software Defined Network (SDN) and Network Function Virtualization (NFV) principles in order to realize Service Function Chaining (SFC) in a network. SDN is a new networking paradigm, which makes a network programmable through the use of a software entity called SDN controller. NFV is intended to enable deployment of virtualized network functions, therefore replacing existing hardware solutions. SFC provides the ability to route user traffic to one or more network functions in an orderly manner. SFC will potentially enable many use cases such as data providers being able to dynamically steer user traffic through a set of network functions such as rewall and loadbalancer. This study is based on a set of goals. These goals evolve around the implementation of a prototype that will enable a SDN controller to steer user traffic through a series of virtualized network functions (VNFs). An important part of the prototype setup is a Network Management Software (NMS) named BECS, which is developed by Packetfront Software AB. BECS is acting as an orchestrator on the network and has complete awareness of all the network devices present on the network it manages. One of the main requirements of the prototype is to enable BECS to communicate with a SDN controller. Once that has been achieved, BECS could provide the necessary information that the controller needs in order to create and install a set of forwarding rules in the SDN enabled switches of the network. All those steps are necessary in order to achieve SFC. In this prototype, SFC is realized by demonstrating the user specific traffic steering through a set of VNFs in a specific order, based on control messages originated from BECS. Until now, network architecture has been limited to the capabilities of the actual hardware equipment. SDN and NFV help us to overcome this limitation. Information needs to be available anywhere and at any time, in a reliable and secure way. To ensure that, we propose a new scheme of network architecture through our prototype solution. This solution intends to give the ability to network managers to re-shape their networks based on their needs by the use of SFC. / Denna avhandling syftar till att undersöka hur man kan utnyttja principer för Software Defined Network (SDN) och Network Function Virtualization (NFV) för att förverkliga Service Function Chaining (SFC) i ett nätverk. SDN är en ny typ av nätverksparadigm som gör ett nätverk programmerbart genom användning av en programvaruenhet som kallas SDN controller. NFV syftar till att möjliggöra utbyggnaden av virtualiserade nätverksfunktioner och på så sätt ersätta befintliga hårdvarulösningar. SFC bidrar till en förmåga att dirigera trafiken till en eller flera nätverksfunktioner på ett ordnat sätt. SFC kommer potentiellt att möjliggöra många användningsområden, t.ex. uppgiftslämnare som dynamiskt kommer kunna styra användartrafik genom en uppsättning av nätverksfunktioner såsom firewall och loadbalancer. Studien är baserad på en uppsättning av mål. Dessa mål kretsar kring genomförandet av en prototyp som gör det möjligt för en SDN-styrenhet att styra användartrafik genom en serie av virtualiserade nätverksfunktioner (VNFs). En viktig del av prototypinstallationen ar en Network Management Software (NMS) som heter BECS, vilken är utvecklad av Packetfront Software AB. BECS agerar som en Orchestrator på nätet och har fullständig kännedom om alla nätverksenheter som finns i nätverket som den förvaltar. Ett av de viktigaste kraven for prototypen är att göra det möjligt for BECS att kommunicera med en SDN controller. När detta uppnåtts kunde BECS lämna nödvändiga uppgifter som styrenheten behöver for att kunna skapa och installera en uppsattning vidarebefordrade regler iSDN-aktiverade switchar pa natet. Alla dessa åtgarder är nödvändiga for att uppnå SFC. I denna prototyp realiseras SFC genom att påvisa den användarspecifika trafikstyrningen genom en uppsättning VNFs i en viss ordning, vilket baseras på styrmeddelanden som härstammar fran BECS. Fram till nu har nätverksarkitektur varit begränsad till förmågan hos den faktiska hårdvaruutrustningen. SDN och NFV hjalper oss att undvika denna begränsning. Information måste finnas tillgänglig överallt och när som helst på ett tillförlitligt och säkert sätt. For att säkerställa detta föreslår vi med hjälp av vår prototyplösning ett nytt system for nätverksarkitektur. Denna lösning har för avsikt att ge network managers en förmåga att omforma sina nät baserat på deras behov av SFC-anvandning.

Mobile networks have changed from circuit switched to IP-based mobile wireless packet switched networks. This paradigm shift led to new possibilities and challenges. The development of new capabilities based on IP-based networks is ongoing and raises new problems that have to be tackled, for example, the heterogeneity of current radio access networks and the wide range of data rates, coupled with user requirements and behaviour. A typical example of this shift is the nature of traffic, which is currently mostly data-based; further, forecasts based on market and usage trends indicate a data traffic increase of nearly 11 times between 2013 and 2018. The majority of this data traffic is predicted to be multimedia traffic, such as video streaming and live video streaming combined with voice traffic, all prone to delay, jitter, and packet loss and demanding high data rates and a high Quality of Service (QoS) to enable the provision of valuable service to the end-user. While the demands on the network are increasing, the end-user devices become more mobile and end-user demand for the capability of being always on, anytime and anywhere. The combination of end-user devices mobility, the required services, and the significant traffic loads generated by all the end-users leads to a pressing demand for adequate measures to enable the fulfilment of these requirements. The aim of this research is to propose an architecture which provides smart, intelligent and per end-user device individualised traffic steering for heterogeneous mobile networks to cope with the traffic volume and to fulfil the new requirements on QoS, mobility, and real-time capabilities. The proposed architecture provides traffic steering mechanisms based on individual context data per end-user device enabling the generation of individual commands and recommendations. In order to provide valuable services for the end-user, the commands and recommendations are distributed to the end-user devices in real-time. The proposed architecture does not require any proprietary protocols to facilitate its integration into the existing network infrastructure of a mobile network operator. The proposed architecture has been evaluated through a number of use cases. A proof-of-concept of the proposed architecture, including its core functionality, was implemented using the ns-3 network simulator. The simulation results have shown that the proposed architecture achieves improvements for traffic steering including traffic offload and handover. Further use cases have demonstrated that it is possible to achieve benefits in multiple other areas, such as for example improving the energy efficiency, improving frequency interference management, and providing additional or more accurate data to 3rd party to improve their services.

There has been a steady growth in the traffic generated by Mobile Network Operators (MNOs), and by 2020 it is expected to overload the existing licensed spectrum capacity and lead to the problem of scarce resources. One method to deal with this traffic overload is to access unlicensed and shared spectrum bands using an opportunistic approach. The use of Licensed Shared Access (LSA) is a novel approach for spectrum sharing between the incumbent user (i.e., the current owner of the shared spectrum) and the LSA licensee (i.e., the temporary user of frequencies, such as an MNO). The LSA system allows the incumbent users to temporarily provide the LSA licensee with access to its spectrum resources. However, licensees must adopt vertical handover and traffic steering procedures to vacate their customers from the LSA band without causing interference, whenever this is required by the incumbent. These procedures should be carried out, de facto, before the base station is turned off as a part of a rapid release of unscheduled LSA band facing evacuation scenarios. Thus, in this dissertation, a cognitive mechanism is proposed to make decisions in advance to find the best target network(s) for evacuated customers in connected mode and with active traffic per class of service. On the basis of these decisions, the vertical handover and traffic steering procedures are carried out for the best target network(s), which are selected in advance and undertaken immediately to avoid interference between the licensee and incumbent services. Furthermore, this guarantees the seamless connectivity and QoS of evacuated customers and their traffic respectively, during and after the unscheduled evacuation scenarios. A performance evaluation conducted in a simulating scenario consisting of one LTE-LSA and three Wi-Fi networks, demonstrated that the proposed solution could be completed within the time required for the unscheduled evacuation, as well as, being able to ensure the QoS and seamless connectivity of the evacuees. The total execution time obtained during the performance evaluation of the proposed solution was around 46% faster than of two related works and could thus avoid interference between the licensee and incumbent services.

There has been a steady growth in the traffic generated by Mobile Network Operators (MNOs), and by 2020 it is expected to overload the existing licensed spectrum capacity and lead to the problem of scarce resources. One method to deal with this traffic overload is to access unlicensed and shared spectrum bands using an opportunistic approach. The use of Licensed Shared Access (LSA) is a novel approach for spectrum sharing between the incumbent user (i.e., the current owner of the shared spectrum) and the LSA licensee (i.e., the temporary user of frequencies, such as an MNO). The LSA system allows the incumbent users to temporarily provide the LSA licensee with access to its spectrum resources. However, licensees must adopt vertical handover and traffic steering procedures to vacate their customers from the LSA band without causing interference, whenever this is required by the incumbent. These procedures should be carried out, de facto, before the base station is turned off as a part of a rapid release of unscheduled LSA band facing evacuation scenarios. Thus, in this dissertation, a cognitive mechanism is proposed to make decisions in advance to find the best target network(s) for evacuated customers in connected mode and with active traffic per class of service. On the basis of these decisions, the vertical handover and traffic steering procedures are carried out for the best target network(s), which are selected in advance and undertaken immediately to avoid interference between the licensee and incumbent services. Furthermore, this guarantees the seamless connectivity and QoS of evacuated customers and their traffic respectively, during and after the unscheduled evacuation scenarios. A performance evaluation conducted in a simulating scenario consisting of one LTE-LSA and three Wi-Fi networks, demonstrated that the proposed solution could be completed within the time required for the unscheduled evacuation, as well as, being able to ensure the QoS and seamless connectivity of the evacuees. The total execution time obtained during the performance evaluation of the proposed solution was around 46% faster than of two related works and could thus avoid interference between the licensee and incumbent services.

There has been a steady growth in the traffic generated by Mobile Network Operators (MNOs), and by 2020 it is expected to overload the existing licensed spectrum capacity and lead to the problem of scarce resources. One method to deal with this traffic overload is to access unlicensed and shared spectrum bands using an opportunistic approach. The use of Licensed Shared Access (LSA) is a novel approach for spectrum sharing between the incumbent user (i.e., the current owner of the shared spectrum) and the LSA licensee (i.e., the temporary user of frequencies, such as an MNO). The LSA system allows the incumbent users to temporarily provide the LSA licensee with access to its spectrum resources. However, licensees must adopt vertical handover and traffic steering procedures to vacate their customers from the LSA band without causing interference, whenever this is required by the incumbent. These procedures should be carried out, de facto, before the base station is turned off as a part of a rapid release of unscheduled LSA band facing evacuation scenarios. Thus, in this dissertation, a cognitive mechanism is proposed to make decisions in advance to find the best target network(s) for evacuated customers in connected mode and with active traffic per class of service. On the basis of these decisions, the vertical handover and traffic steering procedures are carried out for the best target network(s), which are selected in advance and undertaken immediately to avoid interference between the licensee and incumbent services. Furthermore, this guarantees the seamless connectivity and QoS of evacuated customers and their traffic respectively, during and after the unscheduled evacuation scenarios. A performance evaluation conducted in a simulating scenario consisting of one LTE-LSA and three Wi-Fi networks, demonstrated that the proposed solution could be completed within the time required for the unscheduled evacuation, as well as, being able to ensure the QoS and seamless connectivity of the evacuees. The total execution time obtained during the performance evaluation of the proposed solution was around 46% faster than of two related works and could thus avoid interference between the licensee and incumbent services.