The majority of people is using multimedia services available through the internet much more nowadays, than a few years ago. The use of the internet based multimedia services is constantly gaining on popularity and slowly becoming an equal opponent to the traditional technologies. Consider the streaming services or the online TV mediation. With nearly everybody owning a smartphone and wideband mobile internet getting widely accessible, one can watch the TV, surf multimedia based websites, whenever and wherever they want to.
Behind the delivery of the multimedia streaming there is a technology called multicast addressing, and the protocols, devices based on this solution. The widely used technology in today’s networks is distributed. On the other hand the concept and architecture of the centralized network control is getting well known. The SDN (Software Designed Network) is a widely supported computer networking architecture, which offers a dynamic, programmable solution for network operation. It’s customizable, scalable, cost-effective. It’s a key factor concept in handling the increasing data load in the future network systems.
The object of this thesis is to implement a fully working controller application operating in an SDN platform. This program enables optimal delivery of multimedia content from streamers to receivers. During its process it builds and maintains a global view of the network (a graph), and runs mathematical algorithms on this structure to compute and build ideal minimal cost paths. The main advantage of this solution compared to other ones lies in the ability of operating centralized. While a distributed system can discover only the local optimum, a centralized one can discover the global one too. Its optimality lies in minimalizing the packet load originating from multimedia services. The comparison between the traditional distributed and the centralized system reveals its beneficial feature, which is mostly the significantly shorter runtime. On the other hand, based on measurements and analysis the thesis assesses a disadvantageous packet loss feature too. However, later it is discovered that this feature has minimal impact, just slightly increasing even when high link delays are present in the network.