Specifications

ALAXALA Ring Configuration Guide (Edition 1)
Copyright © 2008, ALAXALA Networks Corporation. All rights reserved.
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1. What is the Ring Protocol?
1.1 Overview of the Ring Protocol
The Autonomous Extensible Ring Protocol (Ring Protocol) is an ALAXALA-proprietary Layer 2 network
redundancy protocol, which detects failures and performs high-speed path switching in response to detected
failures in a network where switches are connected in rings.
The Spanning Tree Protocol (STP) can be generally used as a provider of Layer 2 network redundancy but
suffers from shortcomings such as slow convergence for path switching when failures occur. The Ring Protocol
achieves faster path switching in case of failures. In addition, the Ring Protocol uses a ring topology, which has
the advantage of using fewer transmission paths and interfaces than the mesh topology that is often used for
spanning trees.
Figure 1.1-1 Normal Ring Protocol operation
Figure 1.1-2 Ring Protocol operation during a failure
M: Master node
T1 - T5: Transit node
HC: Health-check frame
Secondary port
Ring VLAN: BLK
Primary port
Ring VLAN: FWD
Data on the data-transfer VLAN
HC frame on the control VLAN
T1
M
T5
T2 T3 T4
HC
A
failure occurs.
Rin
g
VLAN: BLK -> FWD
T1 M T5
T2 T3 T4
Flush
control
frames
HC