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Chapter 4: Redundancy
4. Redundancy
Redundancy for minimized system downtime is one of the most important concerns for industrial networking devices. Hence,
B-Ring has developed proprietary redundancy technologies including B-Ring, O-RSTP, and Open-Ring featuring faster recovery
time than existing redundancy technologies widely used in commercial applications, such as STP, RSTP, and MSTP. B-Ring’s
proprietary redundancy technologies not only support different networking topologies, but also assure the reliability of the
network.
4.1 B-Ring
4.1.1 Introduction
B-Ring is a proprietary redundant ring technology, with recovery time of less than 10 milliseconds and up to 250 nodes. The ring
protocols identify one switch as the master of the network, and then automatically block packets from traveling through any of
the network’s redundant loops. If one branch of the ring gets disconnected from the rest of the network, the protocol automati-
cally readjusts the ring so that the part of the network that was disconnected can reestablish contact with the rest of the net-
work. The B-Ring redundant ring technology can protect mission-critical applications from network interruptions or temporary
malfunction with its fast recover technology.
4.1.2 Configurations
B-Ring supports three ring topologies: Ring Master, Coupling Ring, and Dual Homing. You can configure the settings in the
interface below.
Table 4-1. Configuration screen components.
Label Description
Redundant Ring Check to enable B-Ring topology.
Ring Master Only one ring master is allowed in a ring. However, if more than one switch are
set to enable Ring Master, the switch with the lowest MAC address will be the
active ring master and the others will be backup masters.
1st Ring Port The primary port when the switch is ring master.
2nd Ring Port The backup port when the switch is ring master.
Coupling Ring Check to enable Coupling Ring. Coupling Ring can divide a big ring into two
smaller rings to avoid network topology changes affecting all switches. It is a good
method for connecting two rings.
Coupling Port Ports for connecting multiple rings. A coupling ring needs four switches to build
an active and a backup link.
Links formed by the coupling ports will run in active/backup mode.
Dual Homing Check to enable Dual Homing. When Dual Homing is enabled, the ring will be
connected to normal switches through two RSTP links (ex: backbone Switch). The
two links work in active/backup mode, and connect each ring to the normal
switches in RSTP mode.
Apply Click to apply the configurations.
NOTE: Do not set one switch as ring master and coupling ring at the same time, because this could cause heavy
loading.