Cisco ONS 15454 SDH, Procedure Manual

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Cisco ONS 15454 SDH Procedure Guide, R7.0
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Chapter 17 DLPs D1 to D99
DLP- D69 Set Up External or Line Timing
•
Framing—Choose the framing used by your BITS reference, either unframed , FAS , FAS + CAS ,
FAS + CRC , or FAS + CAS + CRC . If you selected 2 MHz, the framing option is disabled.
• Sync Messaging—Select the check box to enable synchronization status messages (SSMs). SSM is
used to deliver clock quality. The SSMs supported in SDH are G811, STU, G812T, G812L, SETS,
DUS (ordered from high quality to low quality). If you selected 2 MHz, the SSM option is disabled.
•
Admin SSM—If the Sync Messaging check box is not checked, you can choose the SSM from the
drop-down list.
• Sa bit—Choose one of 5 Sa bits ( Sa4 , Sa5 , Sa6 , Sa7 , or Sa8 ). The Sa bit transmits the SSM message.
If you selected 2 MHz, the Sa bit option is disabled.
Step 8
In the BITS Out area, complete the following information, as needed:
• Facility Type—choose the BITS Out signal type, either E1 or 2 MHz .
•
BITS Out State—If equipment is connected to the node’s BITS output pins on the backplane and
you want to time the equipment from a node reference, set the BITS Out State for BITS-1 and/or
BITS-2 to
unlocked , depending on which BITS Out pins are used for the external equipment. If
equipment is not attached to the BITS output pins, set the BITS Out State to locked .
Step 9 If the BITS Out State is set to locked , continue with Step 10 . If BITS Out State is set to unlocked ,
complete the following information:
•
Coding—Choose the coding used by your BITS reference, either HDB3 or AMI . If you selected
2 MHz, the coding option is disabled.
• Framing—Choose the framing used by your BITS reference, either unframed , FAS , FAS + CAS ,
FAS + CRC , or FAS + CAS + CRC . If you selected 2 MHz, the framing option is disabled.
•
AIS Threshold—Sets the quality level at which a node sends an alarm indication signal (AIS) from
the BITS-1 Out and BITS-2 Out FMEC connectors. When a node times at or below the AIS
threshold quality, an AIS is raised. (The AIS threshold is used when SSM is disabled or framing is
set to unframed, FAS, or FAS + CAS.)
• Sa bit—Choose one of 5 Sa bits ( Sa4 , Sa5 , Sa6 , Sa7 , or Sa8 ). The Sa bit transmits the SSM message.
If you selected 2 MHz, the Sa bit option is disabled.
Step 10
Click Apply .
Note
Refer to the Cisco ONS 15454 SDH Troubleshooting Guide to resolve timing-related alarms.
Step 11
Return to your originating procedure (NTP).
Note
When provisioning a line timing reference for the node, you cannot select the protect port of a 1+1
protection group. If a traffic switch occurs on the working port of the 1+1 protection group, the timing
reference of the node automatically switches to the protect port of the 1+1 protection group.