• 5G
• Backhaul
• IEEE 802.11ac
• interference characterization
• Multi-RAT
• Open vSwitch
• OpenDaylight
• OpenFlow
• performance analysis
• SDN
• Wi-Fi
• wireless communications

Abstract
With the introduction of the fourth generation network (4G), mobile data
traffic experienced an exponential increase during the last decade that is
expected to grow up substantially in the coming years with the release
of the fifth generation network (5G). Data rates hundreds of times higher
than the current ones, massive media content and a plethora of new end-
user services will exceed the boundaries of existing network architectures,
calling for the creation of new network paradigms and solutions that are able
to face these challenges. Concepts and visions related to the Information
and Communications Technology (ICT) evolution such as the Internet of
Things (IoT), hundreds of billions connected devices, wearables, Industrial
Internet, etc., describe the range of new services each coming with specific
requirements, that the network will have to handle.
In order to face these challenges, the entire network architecture has to
evolve and adapt. The edge and access networks serve as starting point
of this evolution to reach the adaptability and flexibility required by 5G
networks. Dense Small Cell (SC) deployments seem to be the answer to
the high demand for coverage and capacity, two requirements that are hard
or even impossible to address simultaneously with a conventional mobile
network architecture.
The deployment of heterogeneous and ultra-dense networks also com-
prises the introduction of adaptive network features such as integration of
access nodes, dynamic resource allocation, per-tenant traffic management
etc. In order to achieve these self-management features, new mechanisms
have to be investigated for the backhaul control and data plane manage-
ment. The development of ultra-dense SC networks also requires the use
of alternative technologies when it comes to provide connectivity between
SCs and the core network: traditional wired solutions prove to be infeasi-
ble and costly. Under these circumstances, the use of wireless technologies
to interconnect SCs and provide backhaul connectivity to all of them is a
much more efficient and cheaper solution.
This thesis has the goal to present the design and implementation of a
Software Defined Networking (SDN) based access and backhauling archi-
tecture to face the upcoming challenges of 5G. The architecture aims to
provide mobile connectivity over wireless backhauling infrastructures using
the Institute of Electrical and Electronics Engineers (IEEE) 802.11ac and
IEEE 802.11n standards. First, this thesis describes the benefits of using
SDN-based technologies over traditional architectures. Secondly, a novel
SDN-based backhaul wireless architecture is presented, providing a descrip-
tion of the main features and the hardware used. Extensive experiments
are conducted to discover the most suitable configuration for throughput
maximization and to overcome the performance limitation caused by the
cross channel interference. A description of the access network and its in-
tegration with the existing backhaul architecture is provided. Finally, the
software components required for the IP assignment procedure management
is designed, implemented and validated in the context of the client access
management.