RPR (Resilient Packet Ring)

misc
  • IEEE 802.17 -> CiscoのSRPをベース
  • Standard designed for the optimized transport of data traffic over FIBER RINGS
  • SONET/SDHの50msの復旧を目標
  • RPR works on a concept of dual counter rotating rings called ringlets
  • 復旧手法
    • The avoidance of failed spans is accomplished by using one of two techniques known as “steering” and “wrapping”Under steering if a node or span is broken all nodes are notified of a topology change and they reroute their traffic. In wrapping the traffic is looped back at the last node prior to the break and routed to the destination station.
  • 従来のSONET/SDHとの差
    • SONET/SDH -> 固定の帯域を持つVCを構築 -> 帯域が無駄になる
    • RPR -> パケットベースで回線の全帯域を共有できる
  • 関連
    • SRP (Spatial Reuse Protocol) - Cisco
    • MRP (Metro Ring Protocol) - Foundary
    • DPT (Dynamic Packet Transport)