A-5
Cisco ONS 15454 Installation and Operations Guide
November 2001
AppendixA Circuit Routing
Manual Circuit Routing
FigureA-5 Ethernet shared packet ring routing
•Multicard EtherSwitch circuits can have virtual UPSR segments if the source or destination is not
in the UPSR domain. This restriction also applies after circuit creation; therefore if you create a
circuit with UPSR segments, Ethernet node drops cannot exist anywhere on the UPSR segment (see
Figure A-6).
FigureA-6 Ethernet and UPSR
•VT Tunnels cannot be an endpoint of a UPSR segment. A UPSR segment endpoi nt is w here the
UPSR selector resides.
If Fully Path Protected is chosen, CTC verifies that the route selection is protected at all segments. A
route can have multiple protection domains with each domain protected by a different mechanism.
The following tables summarize the available node connections. Any other combination is invalid and
will generate an error.
55405
Ethernet source
Ethernet destination
Node 4Node 3
Node 1 Node 2
55406
UPSR Segment
Legal
Node 8Node 7
Node 5Node 2
Node 11 Node 11
Node 6
Source
Drop
UPSR Segment
Illegal
Node 8Node 7
Node 5 Node 6
Source
Drop
TableA-1 Bidirectional STS/VT/Regular Multicard EtherSwitch/Point-to-Point (straight) Ethernet
Circuits
# of Inbound Links # of Outbound Links # of Sources # of Drops Connection Type
- 2 1 - UPSR
2 - - 1 UPSR
21--UPSR
12--UPSR
1 - - 2 UPSR
- 1 2 - UPSR
22--Double UPSR
2 - - 2 Double UPSR