الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Nowadays more attention has been given to “Internet of Things” (IoT).
Wireless Sensor Networks (WSNs) is an essential component serving IoT
applications. By networking thousands of nodes, WSNs can be used to observe
remote environment, measure physical phenomena, and many other real-life
applications. To serve such applications, a dedicated WSN would be needed per application where all nodes cooperate to achieve the required task. A more efficient way of serving multiple applications is the Virtual Wireless Sensor Networks
(VWSNs). VWSNs facilitate serving multiple applications using the same WSN
infrastructure. Virtualization in WSN is a recent trend that aims to create a
framework that helps in separating infrastructure from the application layer in WSN. Due to the limitation of the sensor hardware and low power sources of the sensor, it is not efficient to run multiple OS at the level of the sensor infrastructure.
To achieve virtualization in WSN some mechanisms must be developed for VWSN
nodes membership and network maintenance. This can be done by using dynamic reassignment of sensor nodes’ roles in the network. A network can merge with or split from other networks; add sensor nodes or remove them from the VWSN.
Virtual Wireless sensor network imposes a number of conceptual and technical
challenges to be considered in the traditional wireless sensor network such as ecurity, managing limited resources, and quality of services. There are some reasons
that motivate us to work towards providing a new virtual sensor network
architecture. Most of the current VWSNs systems suffer from poor security and
costly solutions. Also, there is a room to enhance the manageability of the
infrastructure resources to make efficient use of these resources by allowing WSN to perform different tasks even when deployed in the same geographical region.
The main objective of this work is to propose an efficient and secure virtual
wireless sensor network that can be used by different applications. To achieve this objective, a new virtual sensor network model is proposed. The proposed model uses a virtual middleware layer that separates the application layer and the WSN sensor
node infrastructure layer. This layer offers mechanisms to handle different issues, including security, routing, and aggregating resources from multiple physical WSN infrastructures to be used by any application. The evaluation results prove that
valuable enhancements of 2.4% in packet delivery rate, 25.04% in network lifetime, and 37.9% in stability period for the proposed framework compared to the baseline frameworks.
Also, we propose a novel scheme named Optimal, Adaptive and Energy driven
Mesh Routing Protocol (OAEMRP). This new scheme gives an equal weight for the
different routing protocol hyperparameters. Also, the new scheme limits the choice
of relay nodes in order to reduce the number of broadcasting messages during the selection process. This leads to the reduction of energy consumption of the entire network. Also, it achie ves a better delivery rate and load balance compared to the state of the art in network virtualization routing techniques. Finally, a comprehensive performance analysis of existing wireless sensor network routing protocols is carried out to measure its efficiency and compatibility in the context of VWSNs. The LEACH, modleach, SEP, and ZSEP cluster-based routing protocols are analyzed using different metrics such as network lifetime, load
balance between nodes, and total residual energy of the network. The results prove that these protocols can support virtualization by controlling some design parameters
such as the simulation area, number of nodes, and base station position.