Extended Subnetwork Connection Protection Networks - Cisco ONS 15600 Reference Manual

Chapter 8 SDH Topologies and Upgrades
The ONS 15600 SDH can support 32 MS-SPRings on the same node. This capability allows you to
deploy an ONS 15600 SDH in applications requiring SDH digital cross-connect systems (DCSs) or
multiple SDH ADMs.
Figure 8-18
4. Ring 2 runs on Nodes 4, 5, 6, and 7. Two MS-SPRings, Ring 1 and Ring 2, are provisioned on Node 4.
Ring 1 uses cards in Slots 4 and 12, and Ring 2 uses cards in Slots 3 and 13.
Note Nodes in different MS-SPRings can have the same or different node IDs.
Figure 8-18 MS-SPRing Subtending from an MS-SPRing
Slot 4
West
Slot 12
East
Node 2
Slot 4
West
Slot 12
East
After subtending two MS-SPRings, you can route circuits from nodes in one ring to nodes in the second
ring. For example, in
normally travel from Node 1 to Node 4 to Node 7. If fiber breaks occur, for example between Nodes 1
and 4 and Nodes 4 and 7, traffic is rerouted around each ring: in this example, Nodes 2 and 3 in Ring 1
and Nodes 5 and 6 in Ring 2.

8.7 Extended Subnetwork Connection Protection Networks

In addition to single MS-SPRings, SNCP rings, and ADM configurations, you can extend
ONS 15600 SDH traffic protection by creating extended SNCP networks. On SONET platforms, this is
referred to as path-protected mesh networks (PPMNs). Extended SNCP rings include multiple
ONS 15600 SDH topologies and extend the protection provided by a single SNCP ring to the meshed
architecture of several interconnecting rings. In an extended SNCP ring, circuits travel diverse paths
through a network of single or multiple meshed rings. When you create circuits, CTC automatically
routes circuits across the extended SNCP ring, or you can manually route them. You can also choose
levels of circuit protection. For example, if you choose full protection, CTC creates an alternate route
for the circuit in addition to the main route. The second route follows a unique path through the network
between the source and destination and sets up a second set of cross-connections.
78-18400-01
shows two MS-SPRings shared by one ONS 15600 SDH. Ring 1 runs on Nodes 1, 2, 3, and
Node 1
Slot 12
East
Slot 4
West
MS-SPRing
Ring 1
Slot 12
East
Slot 4
West
Node 3
Figure 8-18
8.7 Extended Subnetwork Connection Protection Networks
Node 5
Slot 3
West
Slot 13
East
MS-SPRing
Ring 2
Slot 3
Node 4
West
Slot 13
East
Node 7
you can route a circuit from Node 1 to Node 7. The circuit would
Cisco ONS 15600 SDH Reference Manual, Release 9.0
East
Slot 13
Slot 3
West
Node 6
Slot 13
East
Slot 3
West
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