School of
Information Technology and Electrical Engineering

Speaker: Siamak Layeghy
Seminar Date: Fri, 09/02/2018 - 13:30
Venue: 78-420
Host: Assoc Prof Marius Portmann

Seminar Type:  PhD Thesis Review


Software Defined Networks (SDN) is introduced to facilitate innovation in the networking and simplify the creation of new applications. There are domains in which these SDN promises are far from being realised. One such field is the Quality of Service (QoS) routing and Traffic Engineering (TE) in which most of the current SDN facilities deal with very low-level manipulation of traffic.  Despite the vital importance of QoS and TE in today's multimedia networking, these techniques require a lot of effort and challenges to be implemented in SDN. This research addresses this gap by introducing a new northbound interface for SDN. A northbound interface provides the connection between network services and applications that use them. The northbound interface proposed here, which is called Software-defined Constrained Optimal Routing (SCOR), is based on constraint programming techniques to provide a robust, declarative interface for stating networking problems in SDN. The main advantage of SCOR, is to hiding the complexity of solving the problem from the user.  Accordingly, users only state the constraints and utility functions of the routing problem and the solution is provided by a powerful generic solver. It is implemented in the MiniZinc constraint modelling language consisting of nine fundamental constraint programming predicates which cover different aspects of the routing problems. It is shown that this interface (set of predicates) is sufficiently expressive to handle all the known and relevant QoS routing problems. Furthermore, the practicality and scalability of the approach are demonstrated via some example scenarios, with varying network topologies, network sizes and the number of flows.


Siamak Layeghy is a PhD student at the School of Information Technology & Electrical Engineering at the University of Queensland. He received his Bachelor in Telecommunication Engineering and his Master in Electronics Engineering from K.N.Toosi University of Technology, Tehran, Iran.  He has several years’ experience in Network Engineering in Iran’s National Infrastructure Company. His main research interests include Software Defined Networks, Routing and Traffic Engineering and Network Optimisation.