Moxa TN-5518A-8PoE-2GTX-WV-CT-T [4/36] Introduction to communication redundancy

1. Introduction to Communication

Redundancy

Setting up Communication Redundancy on your network helps protect critical links against failure, protects

against network loops, and keeps network downtime at a minimum.

Communication Redundancy allows you 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 is a particularly

important feature for industrial applications, since it could take several minutes to locate the disconnected or

severed cable. For example, if the Moxa switch is used as a key communications component of a production line,

several minutes of downtime could cause a big loss in production and revenue. The Moxa switch supports three

different protocols to support this communication redundancy function:

• Turbo Ring and Turbo Ring V2

• Turbo Chain

• Rapid Spanning Tree and Spanning Tree Protocols (IEEE 802.1W/802.1D-2004)

When configuring a redundant ring, all switches on the same ring must be configured to use the same

redundancy protocol. You cannot mix the Turbo Ring, Turbo Ring V2, and STP/RSTP protocols on the same ring.

The following table lists the key differences between the features of each protocol. Use this information to

evaluate the benefits of each, and then determine which features are most suitable for your network.

Turbo Ring Turbo Ring V2 Turbo Chain STP RSTP

Topology Ring Ring Chain Ring, Mesh Ring, Mesh

Recovery Time < 300 ms < 20 ms < 20 ms Up to 30 sec. Up to 5 sec

NOTE

Most of Moxa’s managed switches now support three proprietary Turbo Ring protocols

Turbo Ring refers to the original 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.

Turbo Chain is a new Moxa proprietary protocol with unlimited flexibility that allows

you to construct any

type of redundant network topology. The recovery time is under 20 ms.

In this manual, we use the terminology

Turbo Ring and Turbo Ring V2 to differentiate between rings

configured for one or the other of these protocols.