Zhone Technologies IMACS-200 - Manual (Page 183)

Sub Rate Data Ports 8-7
SRU Ports SRU port User Screens and Settings
LB
The Loopback setting allows you to activate local loopbacks on the SRU port. These settings
are off, toward the dte (DTE), and toward the net (network). Figure 8-3 shows a diagram of
the local loopback conditions.
Figure 8-3.Local Loopbacks