Filter
Top Products
152-402-145-02, Issue 2 Loopback Operation
H2TU-R-402 June 16, 2000 25
Table 10. Summary of HiGain HDSL2 Loopback Codes and Activation Methods
Method of Activation
Loopback Code Description Test Set Craft Port
H2TU-C
MODE/SEL
NLOC 1111000
4-in-7
DSX-1 signal is looped back to the network at the H2TU-C.
X X X
NREM 1110000
3-in-7
DSX-1 signal is looped back to the network at the H2TU-R.
X X X
CLOC 1111100
5-in-7
DS1 signal from the customer is looped back to the
customer at the H2TU-R.
X X X
CREM 1111110
6-in-7
DS1 signal from the customer is looped back to the
customer at the H2TU-C.
X X X
COLB Dual loopback at H2TU-C. DSX-1 signal is looped back to
the network at the H2TU-C and DS1 signal from the
customer is looped back to the customer at the H2TU-C.
X X
RULB Dual loopback at H2TU-R. DSX-1 signal is looped back to
the network at the H2TU-R and DS1 signal from the
customer is looped back to the customer at the H2TU-R.
X X
(a)
SMJK LpUp
(PL)
11000
2-in-5
SmartJack Loopup or NID payload (PL) code. Invokes
H2TU-R loopback towards network.
X
SMJK LpUp
(ESF-DL)
1111-1111-
0100-1000
SmartJack Loopup or NID (ESF-DL) code. Invokes
H2TU-R loopback towards network.
X
SMJK LpDn
(PL)
11100
3-in-5
SmartJack Loopdown or NID payload (PL) code. Removes
SMJK, NLOC, NREM, CLOC, CREM, CRGx, and NRGx.
X
SMJK LpDn
(ESF-DL)
1111-1111-
0010-0100
SmartJack Loopdown or NID (ESF-DL) code. Removes
SMJK, NLOC, NREM, CLOC, CREM, CRGx, and NRGx.
X
(a) The RULB dual loopback (same as NREM-CLOC) can be activated by pressing the LBK button on the H2TU-R front panel.
HiGain HDSL2 systems feature the SmartJack (SMJK) option which can emulate a Network
Interface Device (NID) for the purpose of loopback testing of the HiGain HDSL2 circuit. SMJK
and NREM loopbacks perform the same functions, but their initiation differs. SMJK indicates
that the loopback was initiated by the 2-in-5 inband command. NREM, on the other hand, is
initiated by the 3-in-7 inband command, by the H2TU-R front panel LBK button, by a command
issued from the maintenance terminal, or by the H2TU-C front panel MODE and SEL buttons.
Use the inband commands to enable or disable the SMJK loopback options. The HiGain HDSL2
system setting is normally enabled to recognize all inband SMJK loopback commands.