Datasheet

12-30
Cisco ONS 15454 SDH Reference Manual, R7.0
October 2008
Chapter 12 SDH Topologies and Upgrades
12.8 Four Node Configurations
12.8 Four Node Configurations
You can link multiple ONS 15454 SDH nodes using their STM-N cards (that is, create a fiber-optic bus)
to accommodate more access traffic than a single ONS 15454 SDH can support. Refer to the
Cisco ONS 15454 SDH Procedure Guide for more information. You can link nodes with STM-4 or
STM-16 fiber spans as you would link any other two network nodes. The nodes can be grouped in one
facility to aggregate more local traffic. Each shelf assembly is recognized as a separate node in the
ONS 15454 SDH software interface and traffic is mapped using CTC cross-connect options.
12.9 STM-N Speed Upgrades
A span is the optical fiber connection between two ONS 15454 SDH nodes. In a span (optical speed)
upgrade, the transmission rate of a span is upgraded from a lower to a higher STM-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. You can perform in-service span upgrades
for the following ONS 15454 SDH cards:
• Single-port STM-4 to STM-16
• Single-port STM-4 to STM-64
• Single-port STM-4 to MRC-12
• STM-16 to STM-64
You can also perform in-service card upgrades for the following ONS 15454 SDH cards:
• Four-port STM-1 to eight-port STM-1
• Single-port STM-4 to four-port STM-4
• STM-16 to MRC-12
• STM-64 to STM64-XFP
Note Since the four-port STM-1 to eight-port STM-1 cards and the single-port STM-4 to four-port STM-4
cards are the same speed, they are not considered span upgrades.
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 an MS-SPRing, all spans in the ring must be upgraded.
The protection configuration of the original lower-rate optical card (two-fiber MS-SPRing, four-fiber
MS-SPRing, SNCP ring, and 1+1) is retained for the higher-rate STM-N card.
To perform a span upgrade on either the STM64-XFP or MRC-12 card with an SFP/XFP (known as
pluggable port modules [PPMs] in CTC), the higher-rate PPM must replace the lower-rate PPM in the
same slot. If you are using a multirate PPM, you do not need to physically replace the PPM but can
provision the PPM for a different line rate. All spans in the network must be upgraded. The 1+1
protection configuration of the original lower-rate PPM is retained for the higher-rate PPM.
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 or PPM types are present.
We recommend 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