IPA Management

The intelligent power adjustment (IPA) function prevents hazardous laser radiation exposure that may hurt human eyes. In this user interface, you can create IPA protection groups, and specify the parameters for boards in an IPA protection group.

Navigation Path

In the NE Explorer, click the NE and select Configuration > IPA Management from the Function Tree.

In the NE Explorer, click the 55NPO2/55NPO2(STND)/55NPO2E and select Configuration > PID IPA Management from the Function Tree.

IPA in a Raman System

As shown in Figure 1 and Figure 2, an IPA pair for the Raman system is configured between stations A and B. When a fiber break occurs on the link between stations A and B, the IPA starts and the optical amplifier and Raman amplifier in the upstream of the fiber break point are shut down to maintain the line optical power on a safe level. When the optical signals of the system are restored, the IPA stops and the optical amplifier and Raman amplifier normally operate again.

Figure 1 Diagram of applying IPA to a Raman system (Backward Raman)

Figure 2 Diagram of applying IPA to a Raman system (Forward Raman)

NOTICE:

Modifying parameters of the IPA with a Raman amplifier forces the laser of the Raman amplifier to be turned on. Avoid direct eye exposure to the laser source.
Before you delete the IPA with a Raman amplifier, make sure that the laser of the Raman amplifier is turned off.

Restart mode of IPA

There are two restart modes of the IPA.

Pulse restart:
In this mode, after receiving an alarm and determining a fiber cut, the IPA shuts down the laser on the control board and then restarts the laser to check whether the line becomes normal.

The pulse restart mode is classified as follows:
- Automatic restart:
  When Laser Restart Mode is set to Automatic and Pulse Restart Switch is set to Enabled, the control implementation board turns on the laser to check whether the line becomes normal every Off Period (s). If the line is normal, the IPA status is canceled. Otherwise, the laser is shut down after On Period (0.01s) and the previous process repeats until the line becomes normal.
- Manual restart:
  This mode is valid only when Laser Restart Mode is set to Manual. After the manual restart of IPA, the laser on the control implementation board remains in the disabled state. After Off Period (s), the laser is turned on to check whether the line becomes normal. If the line is normal, the IPA status is canceled. Otherwise, the laser is shut down after Testing Period (s).
- Test restart:
  This mode is valid only when Laser Restart Mode is set to Manual. After you click Start Test, the laser on the control implementation board is turned on immediately to check whether the line becomes normal. If the line is normal, the IPA status is canceled. Otherwise, the laser is shut down after Testing Period (s).
OSC restart:
When the IPA determines a fiber cut and shuts down the laser, the OSC is not closed. Therefore, after the IPA determines a fiber cut, no restart pulse needs to be sent and the restart depends on whether the related alarm is cleared.

NOTE:
After IPA is created, create the OSC board to make it serve as the auxiliary detection board. Double-click the Pulse Restart Switch field on the IPA Protection interface, the Pulse Restart Switch field can be set to Enabled or Disabled.

Buttons

Button	Description
Query	Queries IPA protection data from the NE.
Apply	Sends the configuration data.
New	Creates IPA.
Delete	Deletes IPA after the confirmation.
Modify	Modifies IPA protection data from the NE.
Restart IPA Manually	Restarts the IPA function manually.
Start to Test	Tests the IPA startup.
Set Delay	Sets the start hold-off time.
Detect Auxiliary Board	Configures detect auxiliary board for an IPA protection group.
Action for faulty	Specifies whether to enable automatic shutdown of the Raman laser after detect board is fault.

Parameters

**Table 1** IPA Management Parameters
Field	Value	Description
Protection Group ID	1-32 Default: 1	The Protection Group ID parameter indicates the index ID of an IPA protection group.
Band	C Default: C	The Band parameter indicates the working band of the optical amplifier unit. This parameter is used to set the working band type of the system that IPA protects.
Detection Board	Equipment that supports the master and slave shelf management: shelf ID(shelf name)-slot number-board name-port number(port name) Equipment that does not support the master and slave shelf management: slot number-board name-port number(port name) <Blank> Default: <Blank>	The Detection Board parameter indicates the board that detects the alarm conditions of starting IPA. The detection board may be HBA, WBA, WPA, WLA, OAU, OBU, OPU, WBA2, WPA2 or WLA2.
Laser Control Board	Equipment that supports the master and slave shelf management: shelf ID(shelf name)-slot number-board name-port number(port name) Equipment that does not support the master and slave shelf management: slot number-board name-port number(port name) Default: -	The Laser Control Board parameter indicates the board that controls the turn-on and shutdown of the laser during IPA. The control implementation board may be HBA, WBA, WPA, WLA, OAU, OBU, OPU, WBA2, WPA2 or WLA2.
Raman Amplifier	Equipment that supports the master and slave shelf management: Equipment type-NE name-shelf ID(subrack name)-slot ID-Raman Amplifier Equipment that does not support the master and slave shelf management: Equipment type-NE name-slot number-Raman Amplifier <Blank> Default: <Blank>	The Raman Amplifier parameter indicates that the Raman amplifier forward or reversely inputs intensive light to the fiber in a system that is configured with the Raman amplifier and adopts IPA. To avoid exposure of human body to the intensive light, when IPA is started, the laser on the Raman amplifier must also be shut down. This parameter is used to specify the Raman amplifier which is jointly used with the control implementation board to shut down the laser. In addition, if the hardware of the configured Raman amplifier supports the detection of loss of optical power alarm, after the Raman Amplifier Threshold is calibrated and Enable Raman Board Alarm is set, the Raman board configured as the Raman Amplifier supports IPA fiber cut detection. If the Raman amplifier is optional, it is not used unless a Raman amplifier is used at the receive end.
Enable Flag	Enabled, Disabled	The Enable Flag parameter indicates whether enable the IPA function.
Laser Restart Mode	Automatic, Manual Default: Manual	The Laser Restart Mode parameter indicates the restart mode of the laser on the control implementation board used for IPA management. NOTE: When the Restart Mode is set to Automatic, the Laser Control becomes Enabled automatically. When the Restart Mode is set to Manual, the Laser Control can be set to Enabled or Disabled.
Off Period (s)	100-300 Default: 100	The Off Period (s) parameter indicates the interval between the time when the laser is shut down because of IPA protection and the time when the laser is turned on if the Restart Mode is set to Auto or you click Manual Restart in the Manual mode. The Off Period (s) parameter is used to set the off time span of the laser before each detection.
On Period (0.01s)	175-4500 Default: 300	The On Period (0.01s) parameter indicates the interval between the time when the laser shut down because of IPA protection is turned on to detect whether the line is restored and the time when the detection stops if the Restart Mode is set to Auto or you click Manual Restart in the Manual mode. The On Period (0.01s) parameter is used to set the on time span of the laser on the control implementation board for each detection. In one IPA protection group, the On Period (0.01s) must be the same.
Start Test Duration (s)	80-1000 Default: 80	The Start Test Duration (s) parameter is used to set the on period of each detection of the laser on the control implementation board in the Test Start mode after IPA is started.
Laser Control	Enabled, Disabled Default: Disabled	The Laser Control parameter is used because after the IPA function is started, if the fiber is not restored after a fault, dormant safety problems exist in the system when the system starts the laser to detect the line status. This parameter is used to control the output optical power of the laser on the control implementation board, to avoid too high optical power on the fiber cut surface.
Status	IPA Start, Alarm Available, Power off, Restart, IPA ended, Power on, Detect under the security mode Default: Unknown	The Status parameter indicates each phase of an IPA protection process.
IPA Detection Board Threshold (dBm)	-35.0 to -14.0 Default: -30.0	The IPA Detection Board Threshold (dBm) parameter need be set when the Raman Amplifier is configured. Because the Raman board influences the input optical power of the detection board, the detection board might still detect low optical power even when the upstream fiber line is cut off. In this case, the system does not report the MUT_LOS alarm. To make the Detection Board correctly detect the line optical power, the IPA alarm detection threshold of the Detection Board need be adjusted. How to set the threshold: First test the input optical power A of the optical amplifier behind the Raman board when the services are normal. Then interrupt the services (by shutting down the laser of the upstream amplifier), open the Raman board, and obtain the input optical power B of the optical amplifier. (A+B)/2 is recommended.
Raman Board Threshold (dBm)	-60 to 0 Default: -60	The Raman Board Threshold (dBm) parameter is set to calibrate the normal optical power threshold of the detection circuit of the Raman board when the Raman Amplifier is configured and the value of Enable Raman Board Alarm is set to Enabled in IPA protection.
Raman Board Alarm Reporting	Enabled, Disabled Default: Disabled	The Raman Board Alarm Reporting parameter indicates that after the Raman Amplifier is configured, if the Raman board and the detection board are in the same service signal flow direction and the value of Raman Board Alarm Reporting is set to Enabled, the Raman board reports an event based on the threshold to the SCC. This event is one of the conditions of starting IPA.
Auxiliary Raman Board	Equipment that supports the master and slave shelf management: shelf ID(shelf name)-slot number-board name Equipment that does not support the master and slave shelf management: slot number-board name Null Default: Null	The Auxiliary Raman Board parameter indicates that when multiple Raman or ROP boards exist on a network section and all these boards are on the line that IPA protects, dormant problems might still exist on the line and threat the safety of maintenance personnel. Hence, in the system, the ROP board which is not configured as the Raman Amplifier can be selected as the Auxiliary Raman Board. When IPA protection is started, the Auxiliary Raman Board, the Raman Amplifier and the ROP Board of the system jointly shut down the lasers at the output optical interface of the local boards. This realizes the dual protection of the line.
Start Delay Time (ms)	10-600 Default: 10	The Start Delay Time (ms) parameter indicates the time of alarm anti-jitter during IPA.
Pulse Restart Switch	Enabled, Disabled Default: Enabled	The Pulse Restart Switch parameter is used in the process that IPA shuts down the laser on the control implementation board when a fiber cut occurs on the line during IPA protection. This parameter is used to set whether to turn on the laser on the shutdown board to send out detecting pulses when IPA is in a process of timed restart in the Auto Restart mode. When Restart Pulse is set to Enabled, during the timed restart of IPA, the IPA turns on the laser on the shutdown board to send out detecting pulses. When Restart Pulse is set to Disabled, during the IPA restart, the IPA does not turn on the laser on the shutdown board.
ROP Board	Equipment that supports the master and slave shelf management: shelf ID(shelf name)-slot number-board name Equipment that does not support the master and slave shelf management: slot number-board name Null Default: Null	Display the ROP board of the IPA group.
Auxiliary Detection Board	Equipment that supports the master and slave shelf management: shelf ID(shelf name)-slot number-board name-port number(port name) Equipment that does not support the master and slave shelf management: slot number-board name-port number(port name) <Blank> Default: <Blank>	Display the auxiliary detection board of the IPA group.
Shutdown Raman lasers on detection faulty	Disable, Enable Default: Disable	Specifies whether to enable automatic shutdown of the Raman laser. If you disable this function, the software does not shut down the Raman laser after all detection boards in an IPA group fail to work. Instead, it reports alarms. Seeing the alarms, users will determine whether to shut down the Raman laser based on the importance of services traversing the IPA group and personal safety.