چكيده به لاتين
Due to the increasing use of computer networks, we need to apply various and efficient methods for network management. In recent years, the »Software-Defined Networks« (SDN) model has been featured by the activists in this area as an approach that employs a network implementation based on less hardware and more reliance on software. In SDN networks, the “control panel” is separated from the “forward panel” of data and are designed and implemented in a programmable way, and this separation of the control layer from the data layer in the SDN networks provides greater flexibility and scalability in the performance of computer networks. One of the main issues in this kind of networks is controller and controller function for controlling network hardware. The controller can not only act as a control system for hardware, it can also manage the network seamlessly and efficiently, and also play the role of an operating system. In fact, it manages the main function of these types of networks, and for this reason, there are challenges for this layer. The controller is responsible for deciding how to send network packages and enforcing its policies through standard protocols such as OpenFlow to network hardware.
In this research, we present a comprehensive framework for evaluating the performance of OpenFlow controllers, and we first introduce a class of controllers based on structural characteristics and type of use (including centralized controllers and distributed controllers). Then, based on a simulation and testing platform, we examine and analyze the existing centralized controllers based on parameters of service quality, latency and controller throughput in a variety of network topologies such as linear, tree, and individual, as well as different scales. In order to evaluate distributed controllers, the selection criterion is based on network latency criteria in a variety of topologies in data center networks according to different scale and uploads on the network, and also the effect of using routing protocols on controllers’ performance in data center networks is evaluated and analyzed.
