Applying flexibility in scale-out-based web cloud to future telecommunication session control systems

In traditional telecommunication networks, server resources are statically allocated to session control systems based on demand forecasting. However, the open platform on which third party developers provide various applications has recently made demand prediction difficult. In addition, static allocation concerning load peak results in less resource utilization during nonpeak times, and is not capable of handling unexpected demand fluctuation. To enable flexible on-demand resource control in telecommunication systems that reduces costs, we propose applying a scale-out architecture, which is commonly used in Web systems for resource optimization, to high availability telecommunication systems. We implemented a scale-out-based session control server cluster and showed that the number of servers comprising the cluster can be dynamically configured without serious interruption in service. We also confirmed that the performance of the cluster linearly scales to the number of servers, which indicates the feasibility of the scale-out-based telecommunication system architecture.