Allied Telesis AT-S65 - Manual (Page 78)

Chapter 5: Working With Line Cards
78
Default Mode In the default mode (mode 1 shown in Figure 35), missing link is enabled
for both the port (SFP) and line (WDM) sides. This mode allows the
system to pass the status of its connections to the next stage in the data
path.
Figure 35. Mode 1: Missing Link Enabled for Port Side and Line Side
(Default Mode)
For example, if the port (SFP) side of a local AT-LX3800U system in
default mode does not receive a signal (Figure 35, case A), then the
corresponding line (WDM) side is shut down and the remote AT-LX3800U
does not get a signal. If the remote system is also in default mode, then
the corresponding port (SFP) side is shut down. (See Case C in Figure
35.) Therefore, the status of the port side of a local system propagates to
the remote system’s port side.
CWDM
Transciever
SFP
Line
Side
Port
Side
Legend
No optical signal
Optical signal present
CWDM
Transciever
SFP
Line
Side
Port
Side
CWDM
Transciever
SFP
Line
Side
Port
Side
CWDM
Transciever
SFP
Line
Side
Port
Side
Case B:
Port side: optical
signal received
Line side: optical
signal received Case C:
Port side: optical signal
received
Line side: no optical
signal received Case D:
Port side: no optical
signal received
Line side: no optical
signal received Case A:
Port side: no optical
signal received
Line side: optical signal
received
X
X X X X
X
X
X
X X
X X
Case B:
Port side: optical
signal received
Line side: optical
signal received