Specifications

You must have a transceiver selection (Position 6)
for transceiver X1-1 before selecting a transceiver
X1-2. Limitations apply to the possible combina-
tions of transceivers. See Table 2-3 for possible
transceiver combinations.
Hot Standby Fibers are the best method of protec-
tion against loss of channels due to broken fibers.
Switchover to the standby fiber is automatic
whenever a loss of signal is detected. Hot Standby
can only be provided on 1300 nm or 1500 nm,
single or dual laser transceiver modules. For
further information about the Hot Standby feature,
see Chapter 11.
The four-fiber hot standby uses only two pairs of
fibers between all adjacent nodes. One of the fiber
pairs serves as the main communication path, and
the other pair serves as a standby or redundant
path shared by all nodes in the loop.
A break in the primary path between two nodes
initiates rerouting of all 24 channels through the
standby fiber pair. The rerouted signal travels in
the opposite direction around the ring to the node
at the opposite side of the break. This procedure
reliably connects all channels affected by the
break. When the normal path has been restored,
the signals are automatically returned to the main
fibers.
Unlike traditional path-switched schemes, the
four-fiber hot standby option lets you use the full
E1/T1 bandwidth between each adjacent station.
The system provides fast service restoration with
complete reconfiguration in less than 50ms for
most applications. The module maintains high
reliability by continuously monitoring the standby
fibers to ensure their availability in the event of a
fiber link or node failure. For further information
about the Hot Standby feature, see Chapter 11.
None Supplied
(Single Transceiver Module)
N
1550 nm Laser,
Four-Fiber Hot Standby
M
1300 nm Laser,
Four-Fiber Hot Standby
L
1550 nm Laser with Hot Standby
G
1300 nm Laser with Hot Standby
F
Electrical (Unbalanced 75
ΩΩ
)
P
Electrical (Balanced 120
ΩΩ
)
E
1550 nm Laser
C
1300 nm Laser
A
December 2008 Page 2–9
Chapter 2. System Application and Ordering
2
Catalog
Number Transceiver Description
Position
6 / 8 7 / 9
AA Dual 1300 nm Laser
AN Single 1300 nm Laser
C C Dual 1550 nm Laser
C N Single 1550 nm Laser
E/P E/P Dual Electrical
E/P N Single Electrical
F F Dual 1300 nm Laser with HSB
F N Single 1300 nm Laser w/HSB
G G Dual 1550 nm Laser with HSB
G N Single 1550 nm Laser w/HSB
FL Four-Fiber Hot Standby,
1300nm
GM Four-Fiber Hot Standby, 1550
nm
Table 2–3.
Possible Transceiver Module Combinations.