IoT ağlarında kullanılan RPL için ebeveyn temelli yönlendirme algoritması

The number of smart devices connected to Internet is increasing and becoming important day by day. There exists several terminology and definitions for that like Internet of Things (IoT), Internet of Everything (IoE) , Web of Things (WoT), Web of Everything (WoE), Machine-to-Machine (M2M). We generally combine all these definitions under IoT. IoT is a concept and paradigm that considers pervasive presence of the variety of things/objects that through wireless or wired connections and unique addressing schemes (via IPv6) are able to interact with each other and corporate with others to create new applications/services with a common goals. The goal of IoT is to enable things to be connected anytime, anyplace, with anything and anyone using any path/network/infrastructure and any service. IoT is a new revolution of the Internet. IoT is a network of physical objects that contain embedded technology to communicate, interact about their internal states or the external environment using efficient wireless protocols, powerful sensors and cheaper processors. According to the industry analyst firm IDC, the installed IoT devices will grow up to approximately 212 billion devices by 2020, a number that includes 30 billion connected devices. The deployment of wireless sensors networks (WSNs) accessible through the Internet is the result of the growing trend towards enabling the concepts of IoT. Wireless sensors are key elements in IoT networks to connect legacy devices/actuators to Internet. This is mostly achieved by introducing IPv6 over Low power Wireless Personal Area Networks (6LoWPAN) technology standard on top of IEEE 802.15.4. Within this, wireless sensor node gained capability to talk to Internet via its IPv6 address through border router nodes running routing protocols to manage data traffic both in upward and downward. IPv6 Routing Protocol for Low-Power and Lossy Networks (RPL) is the IETF proposed standard protocol for IPv6 constrained networks and designed to be used with 6LoWPAN to control routing traffic between sensor nodes and the Internet cloud. In RPL architecture, Objective Function (OF) methodology determines how RPL nodes translate one or more metrics into ranks, and how to optimize and select routes in a network. In the literature, there are objective functions considering several metrics like OF_0 with hop count, Minimum Rank with Hysteresis Objective Function (MRHOF) with Expected Number of Transmission (ETX) (known, OF_1). As the number of tiny devices are increasing day by day, to distribute data traffic through the load balanced networks gains importance and becomes crucial. None of the developed and/or implemented objective functions in the literature does consider the parent load density. This thesis offers a solution to have a load balanced network based on a new Parent-Aware Objective Function (PAOF). The proposed objective function uses the ETX and the number of parent's values on each sensor node to compute the best path in order to route data packets across the network. We implemented the proposed solution in Contiki OS and evaluated it by means of Cooja simulations, and compared, the results obtained with that of MRHOF. Moreover, various network topologies and traffic types are studied to have an idea about the performance of the introduced approach. Simulation results verified that the proposed solution provides promising results in term of parent load density, parent diversity and end-to-end delay.