Specifications

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Cisco ONS 15454 Troubleshooting and Maintenance Guide
November 2001
Chapter 3 Maintenance
Span Upgrades
The procedure for downgrading is the same as upgrading except you choose DS3 or DS3N from the
Change Card pull-down menu. To begin the downgrade, right click on the slot to be downgraded and
choose Change Card from the pull-down menu as instructed above in Step 4 of the upgrade. Follow the
remaining steps of the upgrade until the downgrade is complete.
3.12 Span Upgrades
A span is the optical fiber connection between two ONS 15454 nodes. In a span upgrade, the
transmission rate of a span is upgraded from a lower to a higher OC-N signal but all other span
configuration attributes remain unchanged. With multiple nodes, a span upgrade is a coordinated series
of upgrades on all nodes in the ring or protection group in which
traffic carried at a lower OC-N rate is
transferred to a higher OC-N
. You can perform in-service span upgrades for the following ONS 15454
cards:
• OC-12 to OC-48
• OC-12 to OC-192
• OC-48 to OC-192
Use the XC10G card, the TCC+ card, Software R3.1 or higher and the new 15454-SA-ANSI shelf
assembly to enable the OC48 IR/STM16 SH AS 1310, OC48 LR/STM16 LH AS 1550, and the
OC192 LR/STM64 LH 1550 cards. See Chapter 4, “Card Reference,” for more information on card
compatibility.
To perform a span upgrade, the higher-rate optical card must replace the lower-rate card in the same slot.
If the upgrade is conducted on spans residing in a BLSR, all spans in the ring must be upgraded. The
protection configuration of the original lower-rate optical card (two-fiber BLSR, four-fiber BLSR,
UPSR, and 1+1) is retained for the higher-rate optical card.
When performing span upgrades on a large number of nodes, Cisco recommends that you upgrade all
spans in a ring consecutively and in the same maintenance window. Until all spans are upgraded,
mismatched card types will be present.
Cisco recommends using the Span Upgrade Wizard to perform span upgrades. Although you can also
use the manual span upgrade procedures, the manual procedures are mainly provided as error recovery
for the wizard. The Span Upgrade Wizard and the Manual Span Upgrade procedures require at least two
technicians (one at each end of the span) who can communicate with each other during the upgrade.
Upgrading a span is non-service affecting and will cause no more than three switches, each of which is
less than 50 ms in duration.
Note Do not perform any other maintenance operations or add any circuits during a span upgrade.
Note Span upgrades do not upgrade SONET topologies, for example, a 1+1 group to a two-fiber BLSR.
See the Cisco ONS 15454 Installation and Operations Guide for topology upgrade procedures.
Warning Do not reach into a vacant slot or chassis while you install or remove a module or a fan. Exposed
circuitry could constitute an energy hazard.