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Cisco ONS 15310-MA SDH Reference Manual, Release 9.1 and Release 9.2
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Chapter 7 Circuits and Tunnels
Virtual Concatenated Circuits
Figure 7-5 Open-Ended VCAT
Open-ended VCAT circuits can originate or terminate on any pair of OC-N ports and you can route
open-ended VCAT circuits using any of the cards and ports supported by VCAT. The CTC circuit
creation wizard provides an additional check box in the VCAT attributes pane to enable Open-VCAT
circuit creation. Enabling the check box differentiates open-ended VCAT from regular VCAT Circuits.
The routing preferences for an open-ended VCAT circuit must be specified in the initial stages of circuit
provisioning. For example, if the circuit is independent fiber routing, then multiple OC-N ports can be
involved. Alternatively, the source of an open-VCAT circuit should always be a card capable of
participating in a VCG. This allows CTC to determine which routing preferences are permissible.
7.7.5.1 Open-Ended VCAT Protection
Table 7-8 summarizes the protection options for open-ended VCAT circuits. Note that members can have
different routing preferences.
240645
Source
Open-ended VCAT Circuit
VCAT-Source
CTC Managed
Network
SONET/SDH Port
SONET/SDH Port
Destination
Destination
End-to-end VCAT Circuit
VCAT-Destination
Non-CTC Managed
Network
Table 7-8 Protection options for Open-Ended VCAT Circuits
Routing Preferences Routing Mode Protection Options
Common fiber Manual/Auto
• Fully protected (Line only)
• Unprotected
• PCA
