Page 881 - 5G Basics - Core Network Aspects

Transport aspects 2

11.4.2.8 Minimum RFEC/NFEC ratio (rnratio_min)

The control parameter rnratio_min shall be set to the same value as the configuration parameter
MINRNRATIO.
The MINRNRATIO is a configuration parameter that indicates the minimal required ratio, RFEC/NFEC, of FEC
code parameters. The ratio is computed as the number of redundancy bytes (RFEC) divided by the total
number of bytes (NFEC) in each FEC codeword.

It is used in the channel-initialization policy (CIpolicy) and in the online reconfiguration (OLR) procedures.
The valid MINRNRATIO values are from 0 to 8/32 in steps of 1/32.

11.4.3 Vectoring configuration parameters

11.4.3.1 FEXT cancellation enable/disable (FEXT_CANCEL_ENABLE)
The control parameter FEXT_CANCEL_ENABLE shall be set to the same value as the configuration
parameter FEXT_CANCEL_ENABLE.
This FEXT_CANCEL_ENABLE is a configuration parameter in the DPU-MIB that enables (if set to ONE) or
disables (if set to ZERO) FEXT cancellation from all the other vectored lines into a line in the vectored group.
If FEXT cancellation is disabled for a line in a particular direction, no FEXT cancellation shall occur from any
other line in the vectored group into that line for the given direction. If FEXT cancellation is disabled for a
line in a particular direction, the probe sequence shall still be sent on that line for estimation of the FEXT
from that line into other lines.

If downstream FEXT cancellation is disabled on line n, then the precoder output for this line shall be equal
to the precoder input (i.e., Z'n=Zn, see Figure 10-1).

This configuration parameter shall be defined independently for the upstream and downstream directions.

11.4.3.2 Downstream requested Xlog subcarrier group size (XLOGGREQds)
This parameter represents the lower bound for the value XLOGGds in the reporting of Xlogpsds (see clause
11.4.1.2.9.2).
Valid values for XLOGGREQds are 1, 2, 4, 8, 16, 32 and 64.
This configuration parameter is defined only for the downstream direction.

11.4.3.3 Downstream requested Xlog disturber line (XLOGDREQds)
This parameter represents the requested value of the VCE_port_index for the disturber line k in the reporting
of Xlogpsds(i) (see clause 11.4.1.2.9.2).
Valid values for XLOGDREQds are 1 to the maximum number of lines supported by the VCE, and different
from the VCE_port_index of current line i.
This configuration parameter is defined only for the downstream direction.

11.4.4 Line performance monitoring parameters

11.4.4.1 Errored second (ES)
An errored second (ES) is declared if, during a 1-second interval, there are one or more crc anomalies, or
one or more los defects, or one or more lor defects, or one or more lpr primitives.

11.4.4.2 Severely errored second (SES)
A severely errored second (SES) is declared if, during a 1-second interval, there are 18 or more crc
anomalies, or one or more los defects, or one or more lor defects, or one or more lpr primitives.
11.4.4.3 Los second (LOSS)

A los second (LOSS) is declared if, during a 1-second interval, there are one or more los defects.

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