Flexible Routing Strategy for Low-latency Transmission in Software Defined Network

Some Internet applications require the network to provide the necessary low-latency performance. However, in traditional IP networks, protocols such as RIP and OSPF cannot provide such flexible services.Currently, there are mainly two methods to achieve low-latency services.The first is to reserve resources for target traffic, which cannot fully use network resources. The second is to use gating mechanism. The gating schedule is complicated to calculate and requires clock synchronization with high precision, so it is mainly used in specific scenarios. To improve the latency performance of network and allocate resources reasonably, this paper proposes a flexible routing strategy based on Segment Routing and network telemetry technology(FRST), which dynamically selects routes according to the delay performance requirements of the target traffic. It sets the trigger threshold for path update to avoid routing fluctuations and uses the active/standby forwarding table mechanism to reduce the packet loss rate in dynamic scenarios. We conduct experiments under the Software Defined Network (SDN) with P4 programmable platform and open network operating system (ONOS), and the results show that FRST improves network latency and throughput performance.