Troubleshooting and System Testing
800-357-104-01, Revision 01
68
September 29, 2000
HMS-357 List 4 and List 5
Table 9.
System Loopback Definitions
Test Point
Loopback Definition
TLB3
(a) (b)
(a) To perform this loopback command, the DS3 and T1/E1 ports can be in any mode other than IN-SRVC.
(b) Copies data in both directions. All other loopbacks send AIS to a disconnected segment.
Terminal loopback to the customer at the DS3 line. Activate from the HXU-358 Test menu.
FLB3
Facility loopback to the network at the DS3 line. Activate from the HXU-358 Test menu.
Terminal Loopback to the network at the DSX-1 line. Activate from the HXU-358 Test menu.
FLB1
Facility loopback to the customer at the DSX-1 line.
RFL
Remote facility loopback from the far-end DS3 line. Activate from the HXU-358 Test menu.
RTL
Remote terminal loopback from the far-end DSX-1 line. Activate from the HXU-358 Test menu.
CREM
Customer remote loopback is activated by selecting the line unit on the Shelf Status Screen and then the Loopback
Mode selection from the HLU Maintenance Terminal Main Menu.
NLOC
Network local loopback is activated by selecting the line unit on the Shelf Status screen and then the Loopback
Mode selection from the HLU Maintenance Terminal Main Menu.
CDUn
(c)
(c) The number of the doubler.
Customer doubler n loopback is activated by selecting the line unit on the Shelf Status screen and then the
Loopback Mode selection from the HLU Maintenance Terminal Main Menu.
NDUn
Network doubler n loopback is activated by selecting the line unit on the Shelf Status screen and then the
Loopback Mode selection from the HLU Maintenance Terminal Main Menu.
CLOC
Customer local loopback is activated by selecting the line of the Shelf Status screen and then the Loopback Mode
selection from the HLU Maintenance Terminal Main Menu.
NREM
Network remote loopback is activated by selecting the line on the Shelf Status Screen and then the Loopback
Mode selection from the HLU Maintenance Terminal Main Menu.