Specifications

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Cisco ONS 15454 Installation and Operations Guide, R3.2
March 2002
Chapter 5 SONET Topologies
Bidirectional Line Switched Rings
Procedure: Upgrade From a Two-Fiber to a Four-Fiber BLSR
Step 1 Log into one of the two-fiber BLSR nodes. In network view:
a. Verify that all spans between BLSR nodes on the network map are green.
b. Click the Alarms tab. Verify that no critical or major alarms are present, nor any facility alarms,
such as LOS, LOF, AIS-L, SF, and SD. In a BLSR, these facility conditions may be reported as
minor alarms.
c. Click the Conditions tab, then click Retrieve Conditions. Verify that no ring switches are active.
If trouble is indicated, for example, a major alarm exists, resolve the problem before proceeding to
Step 2. See the Cisco ONS 15454 Troubleshooting and Maintenance Guide for additional information.
Step 2 Install two OC-48 or OC-192 cards at each BLSR node. You must install the same OC-N card rate as the
two fiber.
Step 3 Enable the ports for each new OC-N card:
a. Display the card in card view.
b. Click the Provisioning > Line tabs.
c. Click Status and choose In Service.
d. Click Apply.
e. Repeat Steps a – d for each new OC-N card at each BLSR node.
Step 4 Connect the fiber to the new cards. Use the same east – west connection scheme that was used to create
the two-fiber connections. Figure 5-13 shows an example.
Step 5 Test the new fiber connections using procedures standard for your site. For example, pull a Tx fiber for
a protect card and verify that an LOS alarm displays for the appropriate Rx card. Do this fiber test for
every span in the BLSR protect ring.
Step 6 Perform a span lockout at each BLSR node:
a. At one of the BLSR nodes, switch to node view. Click the Maintenance > Ring tabs.
b. Under West Switch for the two-fiber BLSR you will convert, select LOCKOUT SPAN. Click Apply
c. Under East Switch, select LOCKOUT SPAN. Click Apply.
d. Repeat Steps a – c at each node in the two-fiber BLSR.
Step 7 Upgrade each node from two-fiber to four-fiber BLSR:
a. At one of the BLSR nodes, switch to node view. Click the Provisioning > Ring tabs.
b. Select the two-fiber BLSR. Click Upgrade.
c. On the Upgrade BLSR dialog box, complete the following:
– Span Reversion—Set the amount of time that will pass before the traffic reverts to the original
working path following a span reversion. The default is 5 minutes.
– West Protect—Assign the east BLSR port that will connect to the east protect fiber from the
pull-down menu. (In Figure 5-13, this is Slot 6.)
– East Protect—Assign the east BLSR port that will connect to the east protect fiber from the
pull-down menu. (In Figure 5-13, this is Slot 13.)
d. Click Ok.
e. Complete Steps a – d at each two-fiber BLSR node.