ADCP-61-471 • Issue 4 • June 2000 • Section 2: Operation and Maintenance

TAD-102

Page 1 of 5

LOOPBACK PROCESS DESCRIPTION

Summary: The HDSL loopback process is similar to other T1 intelligent repeater methods. For Version D and later HLX modules, the HLXC loopback is like an intelligent office repeater loopback. The HLXR loopback and HRX loopback are like an intelligent inline T1 repeater loopback.

The HDSL loopback operation is described by the diagram in Figure 102-1. The four states are:

Disarmed

Armed

Loopup

Loopup/Time-Out Disable

 

 

DISARMED

 

 

 

 

STATE

 

 

 

 

 

 

 

 

ARM

 

ARMING

 

 

 

 

TIME-OUT

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ARMED

 

 

 

 

STATE

 

 

 

 

 

 

 

 

ACTIVATION

 

LOOPUP

DISARM

 

 

 

TIME-OUT

 

 

 

 

DEACTIVATION

LOOPUP

STATE

LOOPUP

TIME-OUT

DISABLE

LOOPUP/NO TIME-OUT

STATE

7077-C

Figure 102-1. Loopback Operation State Diagram

Inband and ESF data link sequences and time-out operations produce the state transitions. These sequences and time-out values are:

Arming sequence (inband or ESF data link)

Activation sequence

Deactivation sequence

Disarming sequence (inband or ESF data link)

Loopup time-out

Arming time-out

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© 2000, ADC Telecommunications, Inc.