Specifications

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Cisco ONS 15530 Planning Guide
OL-7708-01
Chapter 1 System Overview
System Components
Note A Cisco ONS 15530 system without the OSC and the in-band message channel is not known to other
systems in the network and cannot be managed by any NMS. Without the OSC and the in-band message
channel, a Cisco ONS 15530 system must be managed individually by separate Ethernet or serial
connections. Thus, it is important when adding a node to an existing network of Cisco ONS 15530
systems that the added node have appropriate OSC or the in-band message channel support.
OADM Modules
The OADM (optical add/drop multiplexer/demultiplexer) modules are passive devices that optically
multiplex and demultiplex a specific band of 16 ITU wavelengths. The OADM modules supported by
the Cisco ONS 15530 each add and drop a band of channels at a node and pass the other bands through.
To support the 32-channel spectrum, there are eight different 4-channel OADM modules, each
supporting a different band of channels.
In the transmit direction, the OADM modules multiplex signals transmitted by the line cards over optical
cross connections and provide the interfaces to connect the multiplexed signal to the DWDM trunk side.
In the receive direction, the OADM modules demultiplex the signals from the trunk side before passing
them over optical cross connections to the line cards.
Figure 1-16 shows the physical layout of the OADM module for the channels in band A (1–4) along with
a logical view of its multiplexing and demultiplexing functions. Optical signals received from the line
card, the Thru IN connector, and the OSC IN connector are multiplexed and sent through the Trunk OUT
connector. The optical signal received from the Trunk IN connector is demultiplexed and the OSC signal
is sent to the OSC OUT connector; the dropped channels are sent to the line card; and the passed
channels are sent to the Thru OUT connector.