Traffic-Reduction for High-Availability Seamless Redundancy (HSR) Protocol Using Dual Virtual Paths Algorithm

Abstract

The high-availability seamless redundancy (HSR) protocol provides duplicated frame copies of each sent frame, with zero recovery time. This means that even in cases of node or link failure, the destination node will receive at least one copy from the sent frame. Consequently, there is never any network-operation down time. However, the forwarding process with the QuadBox node type is not smart and relies solely only on duplication and random forwarding. Thus, if a unicast frame is sent in any closed-loop network except a ring topology, the frame copies will be spread through all the links until they reach the destination node. In this paper, we present an algorithm called the dual virtual paths (DVP) algorithm. The idea behind our DVP algorithm is to establish dual virtual paths between each HSR node and all the other nodes in the network, except for the QuadBox node type. These virtual paths will be used for unicast traffic type, rather than using the standard HSR transmission process. The DVP algorithm results in less network traffic because there is no duplication or random forwarding, as in the standard HSR protocol. For the sample network selected in this paper, the DVP algorithm shows a 72-73.7% reduction in network traffic and an 85.7-88.9% reduction in the discarded traffic compared to the standard HSR protocol.