Sharif Digital Repository

Software Defined Networking (SDN) provides a logically centralized view of the state of the network, and as a result opens up new ways to manage and monitor networks. In this dissertation a novel approach to network intrusion detection in SDNs is introduced that takes advantage of these attributes. This approach can detect compromised routers that produce faulty messages, copy or steal traffic or maliciously drop certain types of packets. To identify these attacks and the affected switches, we correlate the forwarding state of network---i.e. installed forwarding rules---with the forwarding status of packets---i.e. the actual route packets take in the network and detect anomaly in routes.... 

Many studies have been conducted in plate heat exchangers. However, some effective parameters on the performance have been less considered. It has been demonstrated that heat exchanger performance increases with more uniform flow distribution. It is possible to make the flow distribution more uniform by installing a baffle inside the header. The ‘gap’ or the distance between this baffle and the inlet is one of the important parameters in determining performance but is has been mostly overlooked by previous studies. This study investigates the effects of inlet baffle place on heat exchanger performance. Another important factor is the header geometry. Elongation and reduction in header...