ADC HIGAIN HDSL2 Manual page 27

152-231-116-01, Revision 01
Table 6. H2TU-C-231 List 1F ADC Config Screen Options (Continued)
Screen
ADC Config Screen
Display
Options
Code
H2TU-R DS1 Frame CONV
Conversion
See "H2TU-R DS1
Frame Conversion
(CONV) Option" on
page 20.
HDSL2 BER Threshold (HBER) Option. The HBER option permits the monitoring of loop integrity and
reporting of alarms when excessive errors are detected. The PM primitive used for this purpose is the CRC
checksum performed on the HDSL2 frame for both directions of transmission. It is, therefore, called a block error
rate rather than the bit error rate associated with the DS1 interface. The CRC errors and counts are displayed on
the Monitor screen for both the H2TU-C and H2TU-R. The HBER option allows an alarm to be generated if the
total number of CRCs at either the H2TU-C or H2TU-R exceeds the selected BER threshold during the last
1-minute interval.
•
HBER option = 1E-6. Alarm is generated if CRC > 93
•
HBER option = 1E-7. Alarm is generated if CRC > 9
Once initiated, the HBER count clears when the CRC count drops below the selected threshold. Selecting NONE
inhibits this alarm.
DS1 Line Coding (DS1) Option. The DS1 line code option should always be set to conform to the type of
DS1 service (AMI or B8ZS) being provided by the HiGain system.
H2TU-C Equalization (EQL) Option. Equalization is the configuration of system transmission characteristics
within specified limits. An adaptive equalizer inserts a frequency-shaped loss that corresponds to an equivalent
addition of an appropriate cable length. By simulating the additional cable loss necessary for correct operation,
the equalizer compensates for a range of variation in transmission path characteristics.
Alarm Pattern (ALMP) Option. To improve HiGain compatibility with the switch-to-protect features used in
Digital Loop Carrier (DLC) feeder applications, the H2TU-C-231 has an Alarm Pattern (ALMP) option that
allows you to select either an AIS or LOS DS1 output payload for the following alarms:
• LOSW on any loop
• LOS DS1
Bipolar Violation Transparency (BPVT) Option. The H2TU-C-231 improves compatibility with DLC
feeder applications because of its ability to transmit DS1 BPV occurrences between its DS1 interfaces. This
feature is required to support protection switching in DLC applications. Each DLC terminal must be able to
monitor the integrity of its Receive DS1 payload and then switch to the protect line when the integrity of the path
drops below specific user selected limits. An essential requirement of this feature is the need for each DLC
terminal to detect BPVs in its DS1 input. Standard HDSL systems correct DS1 BPVs at the input and therefore
prevent them from being detected by the DLC terminals to which they are connected. The H2TU-C-231 and its
associated remote units remove this limitation and become BPV transparent by detecting and counting input BPVs
at each end and then by replicating them at the DS1 output port of the distant end.
The BPV count is converted into BPVs at the distant end during the following second at a rate of 1 BPV every
128 DS1 bits up to a maximum of 12000 (BER=7.7 x 10
exceeds the maximum 10
H2TU-C-231 List 1F
Selection Description
OFF Framing functionally determined by the framing option. Frame format
conversion is inhibited at the H2TU-R.
ACON Auto (ACON) detection of framing and potential frame conversion at the
remote.
FCON Auto detection of framing and forced frame format conversion (FCON) at the
H2TU-R.
-3 BER required by most DLC systems.
October 2, 2000
-3 ). This maximum rate is more than adequate since it
Provisioning
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