A new topology discovery protocol for multi-ring interconnected resilient packet rings

Resilient Packet Ring (RPR) is an emerging network architecture and technology designed to meet the requirements of packet-based metropolitan area network (MAN). IEEE 802.17 RPR Draft Standard[1] defines RPR dual-ring topology discovery protocol. In this paper, we propose a new RPR multi-ring interconnected network. RPR multi-ring interconnected network has better resource availability and better bandwidth utilization than RPR dual-ring topology. So how to extend RPR dual-ring topology to RPR multi-ring interconnected network really deserves our attention. RPR multi-ring network is formed by decreasing the scale of standard RPR and interconnecting several small scale standard RPR rings together through cross-stations. The new topology discovery algorithm uses the method of multi-layer subnet topology discovery in clockwise implemented by the multi-ring automatic topology discovery module in cross-station's MAC control layer. Furthermore, we bring forward the unit structure of tree-like bi-direction list and of topology information list. The paper mainly contains the two parts: RPR standard topology discovery algorithm and RPR multi-ring interconnected topology discovery algorithm.