Improvement of high-availability Seamless Redundancy (HSR) traffic performance

High-availability Seamless Redundancy (HSR) is a redundancy protocol for Ethernet (IEEE802.3) networks that provides duplicated frames for separate physical paths with zero recovery time. This means that even in the case of a node or a link failure, there is no stoppage of network operations whatsoever. HSR is suitable for mission critical Ethernet applications, but its main drawback is the extra traffic created due to the redundant frame copies that are generated and circulated inside the network, especially when using multi-broadcast applications, such as video or audio streaming. This downside will degrade the network performance and may cause network congestion or delays. We propose two approaches to solve the abovementioned problem. The first approach is called Quick Removing (QR) and is suited to a ring or connected ring topologies. The idea behind this approach is to remove the redundant frame copies from the network when all the nodes have received one copy from the sent frame and begin to receive a redundant copy. Therefore, the forwarding of the redundant frame copies until they reach the source node (in order to remove them) is not needed in HSR. Instead, removing them at a proper time will reduce the network traffic and retain the HSR network´s availability. For a network illustrated in this paper, a 37.5% reduction in network traffic is achieved with reference to standard HSR. The second approach is called the Virtual Ring (VRing), which is similar to the Virtual Local Area Network (VLAN). The idea is to divide an HSR network (any closed-loop network) into several VRings. Each of them will circulate (isolate) the traffic (frames) of a certain group of nodes within it. Therefore, the traffic of that group will not affect all the other network links or nodes, and this will result in an enhancement of traffic or network security. For the sample network in this paper, the VRing approach shows a 53% reduction of network traffic under the healthy network ca- e and a 42.8-60% reduction under the faulty case in comparison with the standard HSR.