Simulative Performance Analysis of Resilient Packet Ring in Protection Modes

To recover link failure on resilient packet ring (RPR) networks, IEEE 802.17 working group defines two protection mechanisms, steering and wrapping, which can restore a failed network in less than 50 ms. In this study, we focus on the RPR protection mechanisms and the properties of the three different traffic classes defined in RPR for the two mechanisms by simulation. We find that the frame delay caused by protection in comparison with the normal condition is much higher. In the steering mechanism, the head nodes of protected ringlet sections can seize more bandwidth than their downstream nodes. In the wrapping mechanism, the frame delay of unwrapped frames may be influenced by the wrapped frames. In the simulation, we can disclose the pro and con of the two protection mechanisms and show some points to achieve further improvement.