Specifications

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Cisco ONS 15530 Planning Guide
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Chapter 2 Protection Schemes and Network Topologies
Supported Topologies
• Use PSMs only in point-to-point topologies.
• On a multiple shelf node, install the PSM on the shelf connected to the trunk fiber.
• Up to four channels on a single shelf can be protected with trunk fiber based protection.
Supported Topologies
The Cisco ONS 15530 can be used in point-to-point and ring topologies. Point-to-point topologies can
be either protected and unprotected point-to-point. Ring topologies support add/drop nodes and can be
hubbed or meshed. The following sections give a brief overview of these topologies.
Point-to-Point Topologies
In a pure point-to-point topology all channels terminate on the Cisco ONS 15530 nodes at each end of
the trunk. Point-to-point topologies have many common applications, including extending the reach of
GE or SONET, and can be configured for unprotected or for protected operation.
Unprotected Point-to-Point Topology
Figure 2-13 shows a point-to-point topology without protection. In this configuration only one optical
OADM slot is used in each of the Cisco ONS 15530 nodes. The west or east trunk side interface (OADM
module in subslot 0/0 or 0/1) of node 1 connects to the corresponding OADM module on node 2.
Figure 2-13 Unprotected Point-to-Point Topology
For an example configuration of an unprotected point-to-point topology, see Chapter 6, “Example Shelf
Configurations and Topologies.”
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