H3C Technologies H3C S10500 Series Switches - Manual (Page 59)

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RRPP configuration
RRPP overview
The Rapid Ring Protection Protocol (RRPP) is a link layer protocol designed for Ethernet rings. RRPP can
prevent broadcast storms caused by data loops when an Ethernet ring is healthy, and rapidly restore the
communication paths between the nodes in the event that a link is disconnected on the ring.
Background
Metropolitan area networks (MANs) and enterprise networks usually use the ring structure to improve
reliability. However, services will be interrupted if any node in the ring network fails. A ring network
usually uses Resilient Packet Ring (RPR) or Ethernet rings. RPR is high in cost because it needs dedicated
hardware. Contrarily, the Ethernet ring technology is more mature and economical, so it is increasingly
widely used in MANs and enterprise networks.
Rapid Spanning Tree Protocol (RSTP), Per VLAN Spanning Tree (PVST), Multiple Spanning Tree Protocol
(MSTP), and RRPP can eliminate Layer-2 loops. RSTP, PVST, and MSTP are mature. However, they take
several seconds to converge. RRPP is an Ethernet ring-specific data link layer protocol, and it converges
faster than RSTP, PVST, and MSTP. Additionally, the convergence time of RRPP is independent of the
number of nodes in the Ethernet ring. RRPP can be applied to large-diameter networks.
Basic concepts in RRPP
Figure 13 RRPP networking diagram
RRPP domain
The interconnected devices with the same domain ID and control VLANs constitute an RRPP domain. An
RRPP domain contains the following elements—primary ring, subring, control VLAN, master node, transit
node, primary port, secondary port, common port, edge port, and so on.
As shown in
Figure
13 , Domain 1 is an RRPP domain, including two RRPP rings: Ring 1 and Ring 2. All
the nodes on the two RRPP rings belong to the RRPP domain.