Forward error correction | Configuring Controllers | Configuration Guide for Cisco NCS 1004, IOS XR Release 25.x.x

This section explains how Forward Error Correction (FEC) adds redundancy to data transmissions, enabling detection and correction of errors without retransmission in optical networks.

A forward error correction (FEC) method is a data transmission technique that

adds redundant bits to data before transmission,
enables receivers to detect and correct certain types of errors without requiring retransmission, and
enhances data integrity in high-speed network environments, such as optical transport systems.

Feature history

Table 1. Feature history
Feature Name	Release Information	Description
Forward Error Correction (FEC) support on QXP card for Ethernet controllers	Cisco IOS XR Release 7.8.1	FEC is now supported by the 100GE Ethernet controller on the NCS1K4-QXP-K9 card. FEC is supported for all pluggables except QSFP-100G-LR4-S and ONS-QSFP28-LR4.

Forward error correction (FEC) is a feature that is used for controlling errors during data transmission. This feature works by adding data redundancy to the transmitted message using an algorithm. This redundancy allows the receiver to detect and correct a limited number of errors occurring anywhere in the message, instead of having to ask the transmitter to resend the message.

FEC states for Ethernet controller

FEC states for the Ethernet controller define the error correction mode applied to Ethernet interfaces on the NCS 1004. The software automatically enables FEC mode on pluggables installed in the NCS 1004 based on Auto-FEC support.

FEC states for Ethernet controller

This table lists the FEC states for the Ethernet controller.


State	Description
None	FEC is not enabled on the Ethernet controller.
Standard	Standard (Reed-Solomon) FEC is enabled on the Ethernet controller.

FEC configuration is automatically enabled for only the pluggables that support Auto-FEC. If you manually configure FEC, the manual configuration overrides the Auto-FEC.

The supported pluggables for Auto-FEC are:

QSFP-100G-SR4-S
QSFP-100G-CWDM4-S
QSFP-100G-SM-SR
QSFP-100G-AOC-1M
QSFP-100G-AOC-3M
QSFP-100G-AOC-10M
QDD-400-AOC15M
QDD-400G-FR4-S
QSFP-100G-ER4L
QDD-400G-DR4-S
QDD-400G-LR8-S
QDD-4X100G-LR-S

The LR4 pluggable is a 1310nm long range band pluggable that does not require you to enable FEC.

The software automatically enables FEC mode on the pluggables installed in the Cisco NCS 1004. When you upgrade the software of an NCS 1004 with pluggables in the FEC disabled mode, traffic is affected.

This sample shows the running FEC configuration on the LR4 pluggable:


RP/0/RP0/CPU0:ios#show controller HundredGigECtrlr 0/0/0/4
Thu Aug  8 15:41:20.857 IST
Operational data for interface HundredGigECtrlr0/0/0/4:
 
State:
    Administrative state: enabled
    Operational state: Up
    LED state: Green On
    Maintenance: Disabled
    AINS Soak: None
      Total Duration: 0 hour(s) 0 minute(s)
      Remaining Duration: 0 hour(s) 0 minute(s) 0 second(s)
    Laser Squelch: Enabled
 
Phy:
    Media type: Not known
 
Autonegotiation disabled.
 
Operational values:
    Speed: 100Gbps
    Duplex: Full Duplex
    Flowcontrol: None
    Loopback: None (or external)
    BER monitoring:
        Not supported
    Holdoff Time: 0ms

This sample shows the running FEC configuration on the non LR4 pluggable:


RP/0/RP0/CPU0:ios#show controller HundredGigECtrlr 0/0/0/2
Thu Aug  8 15:41:56.457 IST
Operational data for interface HundredGigECtrlr0/0/0/2:
 
State:
    Administrative state: enabled
    Operational state: Up
    LED state: Green On
    Maintenance: Disabled
    AINS Soak: None
      Total Duration: 0 hour(s) 0 minute(s)
      Remaining Duration: 0 hour(s) 0 minute(s) 0 second(s)
    Laser Squelch: Disabled
 
Phy:
    Media type: Not known
    Statistics:
        FEC:
            Corrected Codeword Count: 0
            Uncorrected Codeword Count: 66
 
Autonegotiation disabled.
 
Operational values:
    Speed: 100Gbps
    Duplex: Full Duplex
    Flowcontrol: None
    Loopback: None (or external)
    BER monitoring:
        Not supported
    Forward error correction: Standard (Reed-Solomon)
    Holdoff Time: 0ms

Configure FEC on Ethernet controller

Enable or disable Forward Error Correction (FEC) on an Ethernet controller to ensure compatibility with specific pluggable modules.

Note

The FEC configuration is not required for the supported pluggables. The configuration is required only in the case of non-Cisco qualified non-LR4 pluggables.

Follow these steps to configure FEC on an Ethernet controller:

Procedure

Run the configure controller HundredGigECtrlr R/S/I/P fec { none | standard } command to configure FEC on the Ethernet controller.

Example:

This sample shows how to configure FEC on the Ethernet controller:


RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:ios(config)#controller HundredGigECtrlr 0/1/0/10 fec standard
RP/0/RP0/CPU0:ios(config)#commit

This sample shows the running FEC configuration on the Ethernet controller:


RP/0/RP0/CPU0:BH-SIT2#show controller HundredGigECtrlr 0/1/0/10
Tue Jul 16 15:30:30.165 IST
Operational data for interface HundredGigECtrlr0/1/0/10:

State:
    Administrative state: enabled
    Operational state: Down (Reason: State undefined)
    LED state: Red On
    Maintenance: Disabled
    AINS Soak: None
      Total Duration: 0 hour(s) 0 minute(s)
      Remaining Duration: 0 hour(s) 0 minute(s) 0 second(s)
    Laser Squelch: Disabled

Phy:
    Media type: Not known
    Alarms:
        Current:
            Loss of Frequency Sync Data
    Statistics:
        FEC:
            Corrected Codeword Count: 0
            Uncorrected Codeword Count: 0

Autonegotiation disabled.

Operational values:
    Speed: 100Gbps
    Duplex: Full Duplex
    Flowcontrol: None
    Loopback: None (or external)
    BER monitoring:
        Not supported
    Forward error correction: Standard (Reed-Solomon)
    Holdoff Time: 0ms

FEC states for CoherentDSP controller

FEC states for CoherentDSP controllers define the error correction mode applied to the optical signal on trunk interfaces of the NCS 1004.

FEC states for CoherentDSP controllers

This table lists the FEC states for the CoherentDSP controllers.

Table 2. FEC states for CoherentDSP controllers
State	Description
EnhancedSD15	FEC Soft-Decision 15.
EnhancedSD27	FEC Soft-Decision 27. Default.

Q-margin support

A Q-margin is an optical parameter that

measures the health of an optical link by indicating how much safety margin remains before the signal quality drops below the Forward Error Correction (FEC) threshold,
is calculated using the average bit error rate (BER) of the optical link, and
provides early warning of potential signal degradation, enabling proactive network maintenance.

Feature history

Table 3. Feature history
Feature name	Release information	Description
Enhanced Q-Margin Support	Cisico IOS XR Release 7.3.1	Enhanced Q-Margin is supported for Forward error correction (FEC) and performance monitoring on CoherentDSP Controllers for 1.2T and 1.2TL cards. This enhanced Q-margin value is calculated based on the maximum number of errors for each frame. An attribute that is called instantaneous Q-margin is displayed in the output of the show controllers coherentDSP command. The lower the delta value between the instantaneous Q-margin value with the Q-margin value, the better the FEC performance of the NCS 1004 system. The instantaneous Q-margin values thus help you to optimize the system with continuous error correction in subsea transport networks. Command modified: show controllers coherentDSP

Enhanced Q-Margin support

From Release 7.3.1, enhanced Q-Margin is supported for Forward error correction (FEC) and performance monitoring on CoherentDSP controllers for 1.2T and 1.2TL cards. Enhanced Q-margin provides a better error free signal in the optical link. The enhanced Q-margin value is calculated based on the maximum number of errors per frame. An attribute that is called instantaneous Q-margin is displayed in the output of the show controllers coherentDSP command. The lower the delta value between the instantaneous Q-margin value with the Q-margin value, the better the FEC performance of the NCS 1004 system.

Configure FEC on CoherentDSP controllers

Enable and confirm FEC settings to improve error correction and signal integrity on CoherentDSP controllers.

Follow these steps to configure and verify FEC on CoherentDSP controllers:

Procedure

Run the configure controller coherentDSP R/S/I/P fec {EnhancedSD15 | EnhancedSD27} command to configure FEC on the CoherentDSP.

Example:

This sample shows how to configure FEC on the CoherentDSP controller:


RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:ios(config)#controller coherentDSP 0/0/0/0
RP/0/RP0/CPU0:ios(config-CoDSP)#fec EnhancedSD15
Tue Feb 25 11:25:52.670 UTC
WARNING! Changing FEC mode can impact traffic
RP/0/RP0/CPU0:ios(config-CoDSP)#commit

Run the show controllers coherentDSP to verify the FEC configuration on the CoherentDSP controller.

Example:

This sample shows the FEC configuration on the CoherentDSP controller:


RP/0/RP0/CPU0:ios#show controllers coherentDSP 0/0/0/0                                                                                    
Tue Feb 25 11:26:08.235 UTC                                                                                                                                    

Port                                            : CoherentDSP 0/0/0/0
Controller State                                : Up                 
Inherited Secondary State                       : Normal             
Configured Secondary State                      : Normal             
Derived State                                   : In Service         
Loopback mode                                   : None               
BER Thresholds                                  : SF = 1.0E-5  SD = 1.0E-7
Performance Monitoring                          : Enable                  
Bandwidth                                       : 50.0Gb/s                
Alarm Information:
LOS = 1 LOF = 0 LOM = 0
OOF = 0 OOM = 0 AIS = 0
IAE = 0 BIAE = 0        SF_BER = 0
SD_BER = 0      BDI = 0 TIM = 0   
FECMISMATCH = 0 FEC-UNC = 0       
Detected Alarms                                 : None
Bit Error Rate Information
PREFEC  BER                                     : 0.00E+00 
POSTFEC BER                                     : 0.00E+00 
Q-Factor                                        : 0.00 dB  
Q-Margin                                        : -5.00dB
Instantaneous Q_margin                        :  0 dB


TTI :
        Remote IP addr                          : 0.0.0.0
FEC mode                                        : Soft-Decision 15

AINS Soak                                       : None
AINS Timer                                      : 0h, 0m
AINS remaining time                             : 0 seconds

FEC is configured on the CoherentDSP controller.

Configure FEC on OTN-XP card

Set up FEC to ensure error correction and improved data integrity on OTN-XP cards.

FEC is supported on the CoherentDSP controllers for the OTN-XP card. O-FEC is the default FEC option configured on the card.

From Release 7.3.1, CFP2-DCO trunk is configured with O-FEC.

Note

The options EnhancedSD15 and EnhancedSD27 are not supported on the OTN-XP card.

Note

CFEC is not supported on CFP2-DCO.

Follow these steps to configure and verify FEC on the OTN-XP card:

Procedure

Run the configure controller coherentDSP R/S/I/Pfec OFEC command to configure FEC on the CoherentDSP controller for the OTN-XP card.

Example:

This sample shows how to configure O-FEC option on the CoherentDSP controller for the OTN-XP card:


RP/0/RP0/CPU0:ios#configure
RP/0/RP0/CPU0:ios(config)#controller coherentDSP 0/0/0/0
RP/0/RP0/CPU0:ios(config-CoDSP)#fec OFEC
Tue Feb 25 11:25:52.670 UTC
WARNING! Changing FEC mode can impact traffic
RP/0/RP0/CPU0:ios(config-CoDSP)#commit

Run the show controllers coherentDSP to verify the FEC configuration on the CoherentDSP controller for the OTN-XP card.

Example:

This sample shows the FEC configuration on the CoherentDSP controller for the OTN-XP card:


RP/0/RP0/CPU0:ios#show controllers coherentDSP 0/0/0/0                                                                                    
Tue Feb 25 11:26:08.235 UTC                                                                                                                                    

Port                                            : CoherentDSP 0/0/0/0
Controller State                                : Up                 
Inherited Secondary State                       : Normal             
Configured Secondary State                      : Normal             
Derived State                                   : In Service         
Loopback mode                                   : None               
BER Thresholds                                  : SF = 1.0E-5  SD = 1.0E-7
Performance Monitoring                          : Enable                  
Bandwidth                                       : 50.0Gb/s                
Alarm Information:
LOS = 1 LOF = 0 LOM = 0
OOF = 0 OOM = 0 AIS = 0
IAE = 0 BIAE = 0        SF_BER = 0
SD_BER = 0      BDI = 0 TIM = 0   
FECMISMATCH = 0 FEC-UNC = 0       
Detected Alarms                                 : None
Bit Error Rate Information
PREFEC  BER                                     : 0.00E+00 
POSTFEC BER                                     : 0.00E+00 
Q-Factor                                        : 0.00 dB  
Q-Margin                                        : -5.00dB
Instantaneous Q_margin                        :  0 dB


TTI :
        Remote IP addr                          : 0.0.0.0
FEC mode                                        : O-FEC

AINS Soak                                       : None
AINS Timer                                      : 0h, 0m
AINS remaining time                             : 0 seconds

FEC is configured on the CoherentDSP controller for the OTN-XP card.

Configure FEC on OTN-XP card for QDD-400G-ZRP pluggable

Enable and validate the desired FEC mode (C-FEC or O-FEC) on an OTN-XP card with a QDD-400G-ZRP pluggable, to ensure optimal optical performance and signal integrity.

The QDD-400G-ZRP coherent trunk pluggable supports two types of FEC modes on the OTN-XP card:

C-FEC
O-FEC

You can configure the required FEC mode on the OTN-XP card.

This table lists the datapath trunk rates supported for the QDD-400G-ZRP pluggable module on the OTN-XP card.

Table 4. Datapath trunk rate supported for QDD-400G-ZRP pluggable modules on OTN-XP Card
Datapath trunk rate	Modulation	FEC
4x100GE MXP	16-QAM	CFEC
4x100GE MXP	16-QAM	OFEC
3x100GE MXP	8QAM	OFEC
2x100GE MXP	QPSK	OFEC
400GE TXP	16-QAM	CFEC
400GE TXP	16-QAM	OFEC

Note

On configuring datapath for 400G trunk rate, the default FEC mode enabled is C-FEC mode. For 200G and 300G trunk rates, the only FEC mode enabled is O-FEC mode.

Note

You can migrate from CFEC to OFEC or OFEC to CFEC mode for the 400G trunk rate. The change in FEC mode affects traffic.

Procedure

Run the configure controller coherentDSP R/S/I/Pfec fec-type command to configure FEC on the CoherentDSP controller for the OTN-XP card.

Example:

This sample shows how to configure O-FEC option on the CoherentDSP controller for the OTN-XP card:


RP/0/RP0/CPU0:ios(config)#controller coherentDSP 0/0/0/11 
RP/0/RP0/CPU0:ios(config-CoDSP)#fec OFEC 
Fri Jul 23 18:19:31.204 UTC
WARNING! Changing FEC mode can impact traffic
RP/0/RP0/CPU0:ios(config-CoDSP)#commit
Fri Jul 23 18:19:32.835 UTC

This sample shows how to configure C-FEC option on the CoherentDSP controller for the OTN-XP card:


RP/0/RP0/CPU0:ios(config)#controller coherentDSP 0/0/0/11 
RP/0/RP0/CPU0:ios(config-CoDSP)#fec CFEC 
Fri Jul 23 18:19:31.204 UTC
WARNING! Changing FEC mode can impact traffic
RP/0/RP0/CPU0:ios(config-CoDSP)#commit
Fri Jul 23 18:19:32.835 UTC

Run the show controller coherentDSP to verify the FEC configuration on the CoherentDSP controller with the trunk controller status as C-FEC for the OTN-XP card:

Example:

This sample shows the FEC configuration on the CoherentDSP controller with the trunk controller status as C-FEC for the OTN-XP card:


RP/0/RP0/CPU0:ios#show controller coherentDSP 0/0/0/11 
Fri Jul 23 17:36:45.342 UTC

Port                                            : CoherentDSP 0/0/0/11
Controller State                                : Up
Inherited Secondary State                       : Normal
Configured Secondary State                      : Normal
Derived State                                   : In Service
Loopback mode                                   : None
BER Thresholds                                  : SF = 1.0E-5  SD = 1.0E-7
Performance Monitoring                          : Enable
Bandwidth                                       : 400.0Gb/s

Alarm Information:
LOS = 1 LOF = 0 LOM = 0
OOF = 0 OOM = 0 AIS = 0
IAE = 0 BIAE = 0        SF_BER = 0
SD_BER = 0      BDI = 0 TIM = 0
FECMISMATCH = 0 FEC-UNC = 0     FLEXO_GIDM = 0
FLEXO-MM = 0    FLEXO-LOM = 0   FLEXO-RDI = 0
FLEXO-LOF = 0   
Detected Alarms                                 : None

Bit Error Rate Information
PREFEC  BER                                     : 9.02E-04 
POSTFEC BER                                     : 0.00E+00 
Q-Factor                                        : 9.90 dB 

Q-Margin                                        : 2.70dB 

TTI :
        Remote IP addr                          : 0.0.0.0

FEC mode                                        : C_FEC

Flexo-Mode                                      : Enable
Flexo Details:
        Tx GID                                  : 0
        Rx GID                                  : 0

AINS Soak                                       : None
AINS Timer                                      : 0h, 0m
AINS remaining time                             : 0 seconds

This sample shows the FEC configuration on the CoherentDSP controller with the trunk controller status as O-FEC for the OTN-XP card:


RP/0/RP0/CPU0:ios#show controller coherentDSP 0/0/0/11  
Fri Jul 23 17:46:51.775 UTC

Port                                            : CoherentDSP 0/0/0/11
Controller State                                : Up
Inherited Secondary State                       : Normal
Configured Secondary State                      : Normal
Derived State                                   : In Service
Loopback mode                                   : None
BER Thresholds                                  : SF = 1.0E-5  SD = 1.0E-7
Performance Monitoring                          : Enable
Bandwidth                                       : 400.0Gb/s

Alarm Information:
LOS = 3 LOF = 0 LOM = 0
OOF = 0 OOM = 0 AIS = 0
IAE = 0 BIAE = 0        SF_BER = 0
SD_BER = 0      BDI = 0 TIM = 0
FECMISMATCH = 0 FEC-UNC = 0     FLEXO_GIDM = 0
FLEXO-MM = 0    FLEXO-LOM = 0   FLEXO-RDI = 0
FLEXO-LOF = 1   
Detected Alarms                                 : None

Bit Error Rate Information
PREFEC  BER                                     : 3.36E-04 
POSTFEC BER                                     : 0.00E+00 
Q-Factor                                        : 10.60 dB 

Q-Margin                                        : 4.10dB 

TTI :
        Remote IP addr                          : 0.0.0.0

FEC mode                                        : O_FEC

Flexo-Mode                                      : Enable
Flexo Details:
        Tx GID                                  : 0
        Rx GID                                  : 0

AINS Soak                                       : None
AINS Timer                                      : 0h, 0m
AINS remaining time                             : 0 seconds

This sample shows the FEC configuration on the optics controller with the trunk controller optics as C-FEC for the OTN-XP card:


RP/0/RP0/CPU0:ios#show controller optics 0/0/0/11
Wed Sep 15 00:36:24.383 UTC

 Controller State: Up 

 Transport Admin State: In Service 

 Laser State: On 

 LED State: Green 
 
 Optics Status 

         Optics Type:  QSFP-DD DWDM
         DWDM carrier Info: C BAND, MSA ITU Channel=49, Frequency=193.70THz,
         Wavelength=1547.715nm 

         Alarm Status:
         -------------
         Detected Alarms: None


         LOS/LOL/Fault Status:

         Alarm Statistics:
          
         -------------
         HIGH-RX-PWR = 0            LOW-RX-PWR = 1          
         HIGH-TX-PWR = 0            LOW-TX-PWR = 1          
         HIGH-LBC = 0               HIGH-DGD = 0          
         OOR-CD = 0                 OSNR = 1          
         WVL-OOL = 0                MEA  = 0          
         IMPROPER-REM = 0          
         TX-POWER-PROV-MISMATCH = 0          
         Laser Bias Current = 0.0 %
         Actual TX Power = -8.09 dBm 
         RX Power = -7.31 dBm 
         RX Signal Power = -7.67 dBm 
         Frequency Offset = 81 MHz 
 Performance Monitoring: Enable 

         THRESHOLD VALUES
         ----------------

         Parameter                 High Alarm  Low Alarm  High Warning  Low Warning
         ------------------------  ----------  ---------  ------------  -----------
         Rx Power Threshold(dBm)          3.0      -23.5           0.0          0.0
         Tx Power Threshold(dBm)          0.0      -16.0           0.0          0.0
         LBC Threshold(mA)                N/A        N/A          0.00         0.00

         LBC High Threshold = 90 % 
         Configured Tx Power = -7.00 dBm 
         Configured CD High Threshold = 2400 ps/nm 
         Configured CD lower Threshold = -2400 ps/nm 
         Configured OSNR lower Threshold = 24.00 dB 
         Configured DGD Higher Threshold = 40.00 ps 
         Baud Rate =  59.8437500000 GBd
         Bits per Symbol = 4.0000000000  bits/symbol 
         Modulation Type: 16QAM 
         Chromatic Dispersion 0 ps/nm 
         Configured CD-MIN -2400 ps/nm  CD-MAX 2400 ps/nm 
         Polarization Mode Dispersion = 0.0 ps 
         Second Order Polarization Mode Dispersion = 29.00 ps^2 
         Optical Signal to Noise Ratio = 36.40 dB 
         SNR = 17.30 dB 
         Polarization Dependent Loss = 0.40 dB 
         Polarization Change Rate = 0.00 rad/s 
         Differential Group Delay = 3.00 ps 

 Transceiver Vendor Details
          
         Form Factor            : QSFP-DD
         Name                   : CISCO
         Part Number            : 10-3496-01
         Rev Number             : 11
         Serial Number          : 210153241
         PID                    : QDD-400G-ZRP-S
         VID                    : ES04
         Date Code(yy/mm/dd)    : 20/21/01
         Fiber Connector Type: LC 
         Otn Application Code: Not Set 
         Sonet Application Code: Not Set 
         Ethernet Compliance Code: Not set 
 Transceiver Temperature : 57 Celsius
 AINS Soak                : None 
 AINS Timer               : 0h, 0m
 AINS remaining time      : 0 seconds

This sample shows the FEC configuration on the optics controller with the trunk controller optics as O-FEC for the OTN-XP card:


RP/0/RP0/CPU0:ios#show controller optics 0/3/0/9
Wed Sep 15 00:41:22.027 UTC

 Controller State: Up 

 Transport Admin State: In Service 

 Laser State: On 

 LED State: Green 
 
 Optics Status 

         Optics Type:  QSFP-DD DWDM
         DWDM carrier Info: C BAND, MSA ITU Channel=49, Frequency=193.70THz,
         Wavelength=1547.715nm 

         Alarm Status:
         -------------
         Detected Alarms: None


         LOS/LOL/Fault Status:

         Alarm Statistics:
          
         -------------
         HIGH-RX-PWR = 0            LOW-RX-PWR = 3          
         HIGH-TX-PWR = 0            LOW-TX-PWR = 5          
         HIGH-LBC = 0               HIGH-DGD = 0          
         OOR-CD = 0                 OSNR = 4          
         WVL-OOL = 0                MEA  = 0          
         IMPROPER-REM = 6          
         TX-POWER-PROV-MISMATCH = 0          
         Laser Bias Current = 0.0 %
         Actual TX Power = -11.10 dBm 
         RX Power = -11.56 dBm 
         RX Signal Power = -11.62 dBm 
         Frequency Offset = -66 MHz 
Performance Monitoring: Enable 

         THRESHOLD VALUES
         ----------------

         Parameter                 High Alarm  Low Alarm  High Warning  Low Warning
         ------------------------  ----------  ---------  ------------  -----------
         Rx Power Threshold(dBm)          3.0      -24.5           0.0          0.0
         Tx Power Threshold(dBm)          0.0      -16.0           0.0          0.0
         LBC Threshold(mA)                N/A        N/A          0.00         0.00

         LBC High Threshold = 90 % 
         Configured Tx Power = -10.00 dBm 
         Configured CD High Threshold = 52000 ps/nm 
         Configured CD lower Threshold = -52000 ps/nm 
         Configured OSNR lower Threshold = 21.10 dB 
         Configured DGD Higher Threshold = 67.00 ps 
         Baud Rate =  60.1385467980 GBd
         Bits per Symbol = 4.0000000000  bits/symbol 
         Modulation Type: 16QAM 
         Chromatic Dispersion 0 ps/nm 
         Configured CD-MIN -13000 ps/nm  CD-MAX 13000 ps/nm 
         Polarization Mode Dispersion = 0.0 ps 
         Second Order Polarization Mode Dispersion = 24.00 ps^2 
         Optical Signal to Noise Ratio = 35.70 dB 
         SNR = 19.40 dB 
         Polarization Dependent Loss = 0.20 dB 
         Polarization Change Rate = 0.00 rad/s 
         Differential Group Delay = 1.00 ps 

 Transceiver Vendor Details
          
         Form Factor            : QSFP-DD
         Name                   : CISCO-ACACIA
         Part Number            : DP04QSDD-E
         Rev Number             : A
         Serial Number          : ACA2524006W
         PID                    : QDD-400G-ZRP-S
         VID                    : V01
         Date Code(yy/mm/dd)    : 21/06/18
         Fiber Connector Type: LC 
         Otn Application Code: Not Set 
         Sonet Application Code: Not Set 
         Ethernet Compliance Code: Not set 

 Transceiver Temperature : 62 Celsius
 AINS Soak                : None 
 AINS Timer               : 0h, 0m
 AINS remaining time      : 0 seconds

The requested FEC mode (CFEC or OFEC) is configured and verified on the OTN-XP card CoherentDSP controller for the QDD-400G-ZRP pluggable. The system uses the selected FEC mode for signal transmission.