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ITU ISUP Continuity

Configuration

This section describes configuration required for the ITU ISUP Continuity Check procedure.

Continuity Check

The Continuity Check feature is disabled by default. To enable it, change the following L3P CIC PPL Configuration Byte to 0x04 using the PPL Configure message:

• ITU - Configuration Byte 135

Continuity Recheck

The Continuity Recheck procedure is enabled by default. The default number of retries is 2. These are configurable by modifying the following PPL Configuration Bytes using the PPL Configure message:

• ITU - ISUP CRCS (0x81)

• Change Configuration Byte 10 to 0x00 to disable

• Change Configuration Byte 11 for number of retries

To send a CCR message to the CSP, send the PPL Event Request message with an event value of 0x65. To stop the sending of the CCR message, send event value 0x64.

Call Flows

CCR

The call flow for a CCR test on a circuit.

IAM with a Continuity Request

IAM with a Continuity Request and a PPL Event Indications sent to the host

If the COT test fails, it is retried until it passes or the number of retries (indicated by Configuration Byte 11 of the ISUP CRCS component (0x81)) is reached.

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CCR Sent to Active Channel

The call flow for an error condition where a CCR is sent on an active channel.

International Telecommunications Union (UN)
See Integrated Services Digital Network User Part.
See Circuit Identification Codes.
See Programmable Protocol Language.
Continuity Check Request message (ISUP)
A condition that, when met, drives a state machine from one state to another. A condition that drives a Component out of its current state by invoking an associated primitive.
In PPL, a condition that, when met, drives a state machine (PPL Component) from one state to another, by invoking an associated Primitive. In PPL files, an Event is marked by an arrow and text.