cAdslAtucDmtConfBitSwapEnabled
CISCO-ADSL-DMT-LINE-MIB ·
.1.3.6.1.4.1.9.9.130.1.14.1.7
Object
This object specifies whether the ATU-C performs bitswapping.
Bitswapping attempts to maintain an acceptable margin for
each bin; equalizing the margin across all bins through bit
reallocation, thereby maximizing error performance.
The ATU-C performs bitswapping by monitoring the margin
measured for each bin by the transmitter:
1) If a bin's margin falls below 'target' and the difference,
between the margin and 'target' exceeds 'thresh(f)', then
the ATU-C marks the bin as a 'from' bin.
2) If a bin's margin exceeds 'target' and the difference
between the margin and 'target' exceeds 'thresh(t)', then
the ATU-C marks the bin as a 'to' bin.
Where: 'target' = adslAtucConfTargetSnrMgn
'thresh(f)' = cAdslAtucDmtConfBitSwapFrom
'thresh(t)' = cAdslAtucDmtConfBitSwapTo
The ATU-C attempts to equalize the margin across the bins by
swapping bits out of bins marked 'from' into bins marked 'to'.
When the ATU-C swaps a bit out of bin, it decreases its b(i).
Thus, the bins constellation is smaller, which increases its
margin. When the ATU-C swaps a bit into a bin, it increases
its b(i). Thus, the bins constellation is larger, which
decreases its margin.
In addition, the ATU-R may optionally implement its own
monitoring capability. The ATU-R uses this information to
request the ATU-C to perform bitswapping. When this object
is 'true', the ATU-C must be prepared to accept and properly
handle bitswap requests from the ATU-R.
While bitswapping has its obvious advantages, bitswapping can
have undesirable side effects. It can introduce errors on
lines prone to impulse noise. In this case, it may be desirable
to disable bitswapping.
Context
- MIB
- CISCO-ADSL-DMT-LINE-MIB
- OID
.1.3.6.1.4.1.9.9.130.1.14.1.7- Type
- column
- Access
- readwrite
- Status
- current
- Parent
- cAdslDmtLineConfProfileEntry
- Table
- cAdslDmtLineConfProfileTable
- Siblings
- 13
Values & Constraints
Type Values
1 | true |
2 | false |
Related Objects
Sibling Objects
| Object | Type | Syntax | OID |
|---|---|---|---|
| cAdslLineDmtConfOperatingMode This object specifies the line operating mode being employed
by the ADSL line. An ADSL line uses of one of two operating
modes:
- Automatic
An ATU-C that emplo… | column | Enumeration | .1.3.6.1.4.1.9.9.130.1.14.1.1 |
| cAdslAturDmtConfFastFecSize This object specifies the initial number of FEC redundancy
bytes the ATU-R appends to upstream frames transmitted over
the fast channel during the training sequence. The ATU-C ca… | column | bytes DmtFecSize | .1.3.6.1.4.1.9.9.130.1.14.1.10 |
| cAdslAturDmtConfInterleaveFecSize This object specifies the initial number of FEC redundancy
bytes the ATU-R appends to upstream frames transmitted over
the interleaved channel during the training sequence. The
A… | column | bytes DmtFecSize | .1.3.6.1.4.1.9.9.130.1.14.1.11 |
| cAdslAturDmtConfCodewordSize This object specifies the number of symbols per codeword being
used by the ATU-R for upstream messages on an interleaved
channel during the training sequence. The ATU-C can force… | column | symbols DmtCodewordSize | .1.3.6.1.4.1.9.9.130.1.14.1.12 |
| cAdslAtucDmtConfMinrateBlock This object is used to implement min-rate blocking on DMT
interfaces that support this option. | column | SNMPv2-TCTruthValue | .1.3.6.1.4.1.9.9.130.1.14.1.13 |
| cAdslAtucDmtDualBitmapEnabled This object is used to implement dual bitmap tables for
Annex C compliant DMT interfaces. The bin data for
the DSL interface will appear in cAdslAturDmtBinTable
and cAdslAtucDmt… | column | SNMPv2-TCTruthValue | .1.3.6.1.4.1.9.9.130.1.14.1.14 |
| cAdslLineDmtConfTrainingMode This object specifies the mode employed by the ATU-C and
ATU-R when training against each other. One of two training
modes can be employed:
- Standard
An ATU-C… | column | Enumeration | .1.3.6.1.4.1.9.9.130.1.14.1.2 |
| cAdslAtucDmtConfFastFecSize This object specifies the initial number of FEC redundancy
bytes the ATU-C appends to downstream frames transmitted over
the fast channel during the training sequence. The ATU-C … | column | bytes DmtFecSize | .1.3.6.1.4.1.9.9.130.1.14.1.3 |
| cAdslAtucDmtConfInterleaveFecSize This object specifies the initial number of FEC redundancy
bytes the ATU-C appends to downstream frames transmitted over
the interleaved channel during the training sequence. The… | column | bytes DmtFecSize | .1.3.6.1.4.1.9.9.130.1.14.1.4 |
| cAdslAtucDmtConfCodewordSize This object specifies the number of symbols per codeword being
used by the ATU-C for downstream messages on an interleaved
channel during the training sequence. The ATU-C can fal… | column | symbols DmtCodewordSize | .1.3.6.1.4.1.9.9.130.1.14.1.5 |
| cAdslAtucDmtConfOverheadFraming This object specifies the overhead framing structure which the
ATU-C will request when establishing a link with the ATU-R.
The value of 'structure0' is not valid. | column | DmtOverheadFraming | .1.3.6.1.4.1.9.9.130.1.14.1.6 |
| cAdslAtucDmtConfBitSwapFrom Bitswapping attempts to maintain an acceptable margin for
each bin; equalizing the margin across all bins through bit
reallocation, thereby maximizing error performance.
… | column | dB Integer32 | .1.3.6.1.4.1.9.9.130.1.14.1.8 |
| cAdslAtucDmtConfBitSwapTo Bitswapping attempts to maintain an acceptable margin for
each bin; equalizing the margin across all bins through bit
reallocation, thereby maximizing error performance.
… | column | dB Integer32 | .1.3.6.1.4.1.9.9.130.1.14.1.9 |