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Diagnostics

Overview

The DS3 card set has some internal diagnostic functions. You can also set the DS3 card to loopback diagnostic mode.

DS3 Card Diagnostics

Diagnostics include:

• Detection of carrier group alarm

• Loss of frame

• Signal

• Carrier group alarm generation

Statistics for errors and alarms are gathered to support Request for Comment (RFC) 1407. Statistics can also be retrieved by the host using the Generic Report (0x46) message.

Loopback Diagnostics

Using the Loopback entity, the DS3 Configure/Query message (0x000F) loops the inbound DS3 stream back to the outbound DS3 stream. This message can also request the far end to go into loopback mode.

Setting Up Loopback Mode

Follow the steps below to place a DS3 span into loopback mode.

1. Take the DS3 span out of service by using Assign Logical Span ID.

2. Use the DS3 Configure/Query message (0x000F) message to loopback the span.

Important! The Loop Timing Configure (0x4A) message is not supported because DS3 is not intended to be a loop timing source. You can get clock source timing off a T1 span or an external BITS source.

A type of diagnostic test in which the transmitted signal is returned to the sending device after passing through a data communications link or network.
Range of channels provided by T1 or E1 transmission service. A physical span is a group of channels taking up a single physical wire. A logical span is a group of channels taking up less than a single logical wire, or carried over more than one physical wire.
Digital communications link - voice, data, and video at a 1.544 Mbps rate (24 64 Kbps channels)