Specifications

5-20
Cisco ONS 15454 Installation and Operations Guide, R3.2
March 2002
Chapter 5 SONET Topologies
Bidirectional Line Switched Rings
• If the new node will connect to third party equipment that cannot transport the K3 byte, use the
“Remap the K3 Byte” procedure on page 5-14 to remap OC48AS cards trunk card that connects to
the third party equipment. Make sure the trunk card at the other end of the span is mapped to the
same byte set on the new node.
• Provision the BLSR using the “Provision the BLSR” procedure on page 5-15
Step 5 Log into the node that will connect to the new node through its east port (Node 4 in the Figure 5-16
example).
Step 6 Switch protection on the east port:
a. Click the Maintenance > Ring tabs.
b. From the East Switch list, choose FORCE RING. Click Apply.
Performing a FORCE switch generates a manual switch request on an equipment (MANUAL-REQ)
alarm. This is normal.
Caution Traffic is unprotected during a protection switch.
Step 7 Log into the node that will connect to the new node through its west port (Node 1 in the Figure 5-16
example).
Step 8 Switch protection on the west port:
a. Click the Maintenance > Ring tabs.
b. From the West Switch list, choose FORCE RING. Click Apply.
Step 9 Following the diagram that you created in Step 1, remove the fiber connections from the two nodes that
will connect directly to the new node.
a. Remove the east fiber from the node that will connect to the west port of the new node. In the
Figure 5-16 example, this is Node 4/Slot 12.
b. Remove the west fiber from the node that will connect to the east port of the new node. In the
Figure 5-16 example, this is Node 1/Slot 5.
Step 10 Replace the removed fibers with fibers that are connected to the new node. Connect the west port to the
east port and the east port to the west port. Figure 5-17 shows the BLSR in the Figure 5-16 example after
the node is connected.