8-21
Cisco ONS 15600 SDH Reference Manual, Release 9.0
78-18400-01
Chapter 8 SDH Topologies and Upgrades
8.8 In-Service Topology Upgrades
Figure 8-20
Extended SNCP Virtual Ring
8.8 In-Service Topology Upgrades
Topology upgrades can be performed while the network is in service to convert a live network to a
different topology. An in-service topology upgrade is potentially service-affecting, and generally allows
a traffic hit of 50 ms or less.
Traffic might not be protected during the upgrade. The following in-service
topology upgrades are supported:
•
Point-to-point or linear ADM to two-fiber MS-SPRing
•
Node addition or removal from an existing topology
You can perform in-service topology upgrades irrespective of the service state of the involved
cross-connects or circuits, however all circuits must have a DISCOVERED status.
ONS 15600 SDH circuit types supported for in-service topology upgrades are:
•
Virtual containers (VC)
•
Unidirectional and bidirectional
•
Automatically routed and manually routed
•
CTC-created and TL1-created
•
Ethernet (unstitched)
•
Multiple source and destination (both sources should be on one node and both drops on one node)
You cannot upgrade stitched Ethernet circuits during topology conversions.
Note
A database restore on all nodes in a topology returns converted circuits to their original topology.
STM-64 SNCP
STM-16
STM-16
159619
ONS 15600 SDH
Node 5
ONS 15454 SDH
Node 1
ONS 15454 SDH
Node 6
ONS 15600 SDH
Node 2
ONS 15600 SDH
Node 4
ONS 15454 SDH
Node 8
ONS 15454 SDH
Node 3
ONS 15600 SDH
Node 7