Fec And E-Fec Modes - Cisco ONS 15454 DWDM Installation And Operation Manual

16.8.5 MXP_2.5G_10E Card

16.8.5.9 FEC and E-FEC Modes

As client side traffic passes through the MXP_2.5G_10E card, it can be digitally wrapped using FEC
mode error correction or E-FEC mode error correction (or no error correction at all). The FEC mode
setting provides a lower level of error detection and correction than the E-FEC mode setting of the card.
As a result, using E-FEC mode allows higher sensitivity (lower OSNR) with a lower BER than FEC
mode. E-FEC enables longer distance trunk-side transmission than with FEC.
The E-FEC feature is one of three basic modes of FEC operation. FEC can be turned off, FEC can be
turned on, or E-FEC can be turned on to provide greater range and lower BER. The default mode is FEC
on and E-FEC off. E-FEC is provisioned using CTC.
16.8.5.10 SONET/SDH Overhead Byte Processing
The card passes the incoming SONET/SDH data stream and its overhead bytes for the client signal
transparently. The card can be provisioned to terminate regenerator section overhead. This is used to
eliminate forwarding of unneeded layer overhead. It can help reduce the number of alarms and help
isolate faults in the network.
16.8.5.11 Client Interface Monitoring
The following parameters are monitored on the MXP_2.5G_10E card:
• Laser bias current is measured as a PM parameter
• LOS is detected and signaled
• Rx and Tx power are monitored
The following parameters are monitored in real time mode (one second):
• Optical power transmitted (client)
• Optical power received (client)
In case of loss of communication (LOC) at the DWDM receiver or far-end LOS, the client interface
behavior is configurable. AIS can be invoked or the client signal can be squelched.
16.8.5.12 Wavelength Identification
The card uses trunk lasers that are wave-locked, which allows the trunk transmitter to operate on the ITU
grid effectively.
over eight wavelengths at 50-GHz spacing or four at 100-GHz spacing.
Table 16-60
Band
30.3
30.3
30.3
30.3
34.2
34.2
Cisco ONS 15454 DWDM Installation and Operations Guide, R6.0
16-104
Table 16-60 describes the required trunk transmit laser wavelengths. The laser is tunable
MXP_2.5G_10E Trunk Wavelengths
Wavelength (nm)
1530.33
1531.12
1531.90
1532.68
1534.25
1535.04
Chapter 16 Card Reference
April 2006