Graduate Program in Computer Engineering.Alagöz, Fatih.Selvi, Hakan.2023-03-162023-03-162015.CMPE 2015 S46https://digitalarchive.library.bogazici.edu.tr/handle/123456789/12295Software-de ned networking (SDN) has been proposed as a new networking paradigm which separates the control and data forwarding planes. The controllers which are centralized network control entities are crucial for meeting the performance and e ciency requirements of these systems. The placement of these network entities, switch assignment and their load-aware operation is a challenging research question. Although various load-balancing schemes are proposed in the literature, this research topic is yet to be explored adequately. In this thesis, we discuss load-balancing issues in SDN and propose a load-balancing scheme, namely Cooperative Load Balancing Scheme For Hierarchical SDN Controllers (COLBAS). Moreover, we evaluate the performance of this scheme and investigate important trade-o s.Software-defined networking (Computer network technology)