SDN replaced deployment and real-time QoS provisioning based on network models

From industrial communications to real-time internet applications, end-to-end delay guarantee is one of the most important aspects of quality of service (QoS). As a new networking paradigm, software-defined networking (SDN) exposes an opportunity to provide this guarantee. In exploiting SDN, We can replace the legacy network devices to SDN forwarding units (SDN-FUs gradually. This paper focuses on the SDN replaced deployment problem, striving for providing real-time QoS provisioning in a network meanwhile. Utilising previous works originated from network calculus, we first propose the candidate nodes selection methods for upgrading legacy nodes to SDN-FUs and then present a routing algorithm located on SDN controller to direct the running of SDN-FUs. Via a simulation about a small network, we show that the delay of a flow passing through a network can reduce significantly with the usage of SDN.