User`s manual

NPort S8000 Series Switch Featured Functions
6-5
The Communication Redundancy function allows the user to set up redundant loops in the network to provide
a backup data transmission route in the event that a cable is inadvertently disconnected or damaged. This
feature is particularly important for industrial applications, since it could take several minutes to locate the
disconnected or severed cable. For example, if the NPort S8000 is used as a key communications component
of a production line, several minutes of downtime could result in a big loss in production and revenue. The NPort
S8000 supports three different protocols to support this communication redundancy function— Rapid
Spanning Tree/ Spanning Tree Protocol (IEEE 802.1W/1D), Turbo Ring, and Turbo Ring V2.
When configuring a redundant ring, all NPort S8000s on the same ring must be configured to use the same
redundancy protocol. You cannot mix the “Turbo Ring,” “Turbo Ring V2,” and RSTP protocols on the same ring.
The following table lists the key differences between each feature. Use this information to evaluate the benefits
of each, and then determine which features are most suitable for your network.
Turbo Ring V2 Turbo Ring RSTP
Topology Ring Ring Ring, Mesh
Recovery Time < 20 ms < 300 ms Up to 5 sec
NOTE
Most of Moxa’s managed switches now support two proprietary Turbo Ring protocols:
“
Turbo Ring” refers to the or
iginal version of Moxa’s proprietary redundant ring protocol, which has a recovery
time of under 300 ms.
“
Turbo Ring V2” refers to the new generation Turbo Ring, which has a recovery time of under 20 ms.
In this manual, we use the terminology
“Turbo Ring” ring and “Turbo Ring V2” ring to differentiate between
rings configured for one or the other of these protocols.
The Turbo Ring Concept
Moxa developed the proprietary Turbo Ring protocol to optimize communication redundancy and achieve a
faster recovery time on the network.
The Turbo Ring and Turbo Ring V2 protocols identify one NPort S8000 as the master of the network, and then
automatically block packets from traveling through any of the network’s redundant loops. In the event that one
branch of the ring gets disconnected from the rest of the network, the protocol automatically readjusts the ring
so that the part of the network that was disconnected can reestablish contact with the rest of the network.
Initial setup of a “Turbo Ring” or “Turbo Ring V2” ring
1.
For each NPort S8000 in the ring, select any two ports as the
redundant ports.
2. Connect redundant ports on neighboring NPort S8000 or
switches to form the redundant ring.
The user does not need to configure any of the NPort S8000 or switches as the master to use Turbo Ring or
Turbo Ring V2. If none of the NPort S8000 switches in the ring is configured as the master, then the protocol
will automatically assign master status to one of the switches. In fact, the master is only used to identify which
segment in the redundant ring acts as the backup path. In the following subsections, we explain how the
redundant path is selected for rings configured for Turbo Ring, and Turbo Ring V2.