ADTRAN Total Access SHDSL LTU Installation And Maintenance Practice page 12

Loopback Type
Remote Customer
Transparent
Loopback
Local Customer
Nontransparent
Loopback
Remote Customer
Nontransparent
Loopback
12
Table 7. Loopback Types (Continued)
Description
Initiated at the LTU and provides a loopback at
the NTU in the customer direction. Data is
passed transparently to the network side.
Provides a loopback at the LTU in the
customer direction. AIS signal is injected into
the network side.
Initiated at the LTU and provides a loopback at
the NTU in the customer direction. AIS signal
is injected into the network side.
Issue 2, July 2004
Illustration
LTU NTU
TX Data
LTU NTU
TX AIS
LTU NTU
TX AIS
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