Verilink PRISM 3030 (34-00208.L) Product Manual - Manual (Page 68)

58 C HAPTER 4: T ERMINAL O PERATION
1 Normal Operation: This diagram depicts the unit’s normal operating mode.
2 NET LLB: The network line loopback command loops data received from the
network back toward the network. Received data is passed through to the DTE
ports.
3 NET PLB: The network payload loopback command loops the network data back
toward the network. Framing, CRC, and FDL are regenerated. Framed all ones are
passed to the DTE ports.
4 NET MLB: The network maintenance loopback command loops data at the T1
DTE port back toward the network (passes network data to the DTE and return
data to the network). MLB affects only network channels assigned to the T1 DTE.
Normal Operation
Network Interface
To Network
From Network
RJ-48C
Framer /Deframer Multiplexer Receivers /Drivers
Receivers /Drivers
BERT Generator /
Detector
DTE (EIA-530 or V.35)
(100' max.)
Framer /Deframer
DTE (DSX1)
RJ-48C
DSX1, 1' -655'
to cross-connect
From
NET
To
NET
To
NET
From
NET
5
4
2
1 To
Ports
From
Ports
5
4
2
1
Network LLB
Network Interface Framer /Deframer Multiplexer Receivers/Drivers
Receivers /Drivers
BERT Generator /
Detector
EIA 530 or V.35
(100' max.)
Framer/Deframer
DTE (DSX1)
RJ-48C
DSX1, 1' -655'
to cross-connect
From
NET
To
NET
To
NET
From
NET
5
4
2
1
To Network
From Network
RJ-48C
5
4
2
1 To
Ports
From
Ports
NET
LLB
1
2
Network PLB
Network Interface Framer /Deframer Multiplexer Receivers/Drivers
NET
PLB
Receivers /Drivers
BERT Generator /
Detector
All ones
to DTE
EIA 530 or V.35
(100' max.)
Framer/Deframer
DTE (DSX1)
RJ-48C
DSX1, 1' -655'
to cross-connect
From
NET
To
NET
To
NET
From
NET
5
4
2
1
To Network
From Network
RJ-48C
5
4
2
1 To
Ports
From
Ports
Network MLB
Network Interface Framer /Deframer Multiplexer Receivers/Drivers
Receivers /Drivers
BERT Generator /
Detector
EIA-530 or V.35
(100' max.)
Framer/Deframer
DTE (DSX1)
RJ-48C
DSX1, 1' -655'
to cross-connect
From
NET
To
NET
To
NET
From
NET
5
4
2
1
NET
MLB
To Network
From Network
RJ-48C
5
4
2
1 To
Ports
From
Ports
3
4
Figure 4-7 Loopback Diagrams