Avoiding data loss is an important operation in data centers. This target could be achieved by several options. One of the common and efficient methods for that is data backup. However, using a private connection to guarantee the Quality of Service (QoS) is a costly operation. Backup services could be offered by cloud providers to reduce the costs by increasing the infrastructure utilization level (multiple users). In addition, QoS level could be guaranteed in cloud providers using different strategies. Software Defined Networking (SDN) is a new networking paradigm. Large IT companies and cloud providers have started to use SDN in their internal networks. SDN depends on the concept of separating data and control planes in classical networks. Using SDN, computer networks could be virtualized and administrated in a simpler and more efficient manner. This research proposes a solution for the problem of guaranteeing the QoS for data centers backup operations over cloud networks using SDN. Data centers need this service as an alternative for costly private network connections. This research introduces an efficient-cost backup model for cloud providers using SDN and AI techniques. It can assure the QoS by choosing the right path (if available) according to the payment, the customer’s requirements and the status of the provider’s network.weiterlesen