The aim of the graduation thesis is to evaluate the current development in the field of SDN and the possibility of programmability of SDN elements using the application programming interface. The first theoretical chapter describes the following: the basic architecture of SDN, the traffic within SDN between its individual layers, the communication protocols Southbound interface and Northbound interface. The second chapter of the thesis deals with the programmability of SDN elements with the help of API. The third theoretical chapter describes the current development in the field of SDN. The practical part of the thesis is devoted to creation of two laboratory tasks dealing with the programming of the SDN API. Laboratory tasks include BIG-IP programming from F5 Network and routers from Arista Network. Programming is done using Python via REST API for BIG-IP, or eAPI for Arista EOS. The Ansible setup tool is also used for the same purpose.

The Thesis focused on hardware based Load balancing solution of web traffic through a load balancer F5 content switch. In this project, the implemented scenario for distributing HTTPtraffic load is based on different CPU usages (processing speed) of multiple member servers.Two widely used load balancing algorithms Round Robin (RR) and Ratio model (weighted Round Robin) are implemented through F5 load balancer. For evaluating the performance of F5 content switch, some experimental tests has been taken on implemented scenarios using RR and Ratio model load balancing algorithms. The performance is examined in terms of throughput (bits/sec) and Response time of member servers in a load balancing pool. From these experiments we have observed that Ratio Model load balancing algorithm is most suitable in the environment of load balancing servers with different CPU usages as it allows assigning the weight according to CPU usage both in static and dynamic load balancing of servers.