Design and Implementation of OpenFlow Networks for Medical Information Systems

In current medical information networks, there is a problem because the cost of core switches is increasing owing to the need to meet demands in terms of throughput and robustness. To address this problem, we propose MediFlow as a medical information network based on OpenFlow. MediFlow replaces expensive, high-performance core switches with a MediFlow core network comprising multiple inexpensive and fully connected OpenFlow switches. The MediFlow core network adaptively allocates the communication capacity to time-varying traffic in a medical information network. If a link fails, MediFlow dynamically assigns a path to ensure that the communication system remains robust. We implemented MediFlow using commercial OpenFlow switches. The experimental evaluation showed that MediFlow could improve the throughput by allocating individual paths to each flow about 7 s after the occurrence of congestion by converging multiple flows. In addition, even if a link failure occurred in the path used by the flow, MediFlow re-established a path with a disconnection time of about 0.7 s.