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Rule 3: Configure OSC Forwarding on TCX1000-RDM20 Before Deploying


This topic describes deployment rule 3 for management communication on the TCX1000-RDM20 and TCX1000-ILA. It describes OSC forwarding and when and how to enable this feature.

OSC Forwarding Overview

Best Practice

Before you deploy a TCX1000-RDM20, you must determine how it will communicate with the proNX Optical Director and enable OSC forwarding if the TCX1000-RDM20 needs to forwarding IP management messages to the remote TCX1000 device.


You configure OSC forwarding through the CLI of the TCX1000-RDM20 using the stp-group parameter under the RSTP DCN0/DCN1 settings. OSC forwarding can only be configured through the CLI on the TCX1000-RDM20.

If the TCX1000-RDM20 is using only direct dual-DCN connections to you DCN HA and is not responsible for communicating management messages over its line port to a remotely connected TCX1000 device, you do not need to configure OSC forwarding. It is disabled by default.

Best Practice

On the TCX1000-RDM20, by default, OSC forwarding is disabled. If you are using OSC management over the Line port on the TCX1000-RDM20 as a redundant path for management communications to the device, you must explicitly enable the OSC forwarding on the TCX1000-RDM20.

For more information on how to enable OSC forwarding on the TCX1000-RDM20, see Enabling OSC Forwarding on the TCX1000-RDM20.


If you deploy a TCX1000-RDM20 at a remote site that has no DCN access without OSC forwarding enabled, you will not be able to remotely manage the TCX1000-RDM20 through proNX Optical Director when a line break occurs in your optical network and the local or the remote TCX1000-RDM20 is not configured to forward OSC management messages over its line port.

You will need to go on site to enable the OSC forwarding on the device.

OSC forwarding must be enabled on the both the local and remote TCX1000-RDM20 devices to have remote connectivity to remote sites.

When and When Not to Use OSC Forwarding on the TCX1000-RDM20

When deploying TCX1000-RDM20 devices, you must identify whether the device needs to forward management messages to the TCX1000 device it will be remotely connected to. The TCX1000-RDM20 uses an OSC forwarding feature that determines whether or not the device forwards management messages over its Line port using the OSC signal. You must enable OSC forwarding when the device is responsible for sending management messages to the device remotely connected to its Line port.

Table 1 describes when and when not to use OSC forwarding on the TCX1000-RDM20.

Table 1: OSC Forwarding Conditions

Enable OSC Forwarding If:

Do Not Enable OSC Forwarding If:

The TCX1000-RDM20 line port is connected to a TCX1000-ILA.

The TCX1000-RDM20 line port is connected to a TCX1000-RDM20 or TCX1000-ILA that is on a different IP subnet.

The TCX1000-RDM20 line port is connected to a TCX1000-RDM20 without DCN access.

Refer to the TCX1000 Programmable ROADM Quick Start Guide   for instructions on how to configure OSC Forwarding.