Cisco ONS 15454 SDH, Руководство по процедурам

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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
Step 3
In the Reference Lists area, complete the following information:
Note
Reference lists define up to three timing references for the node and up to six BITS Out
references. BITS Out references define the timing references used by equipment attached to the
node’s MIC-C/T/P FMEC Timing A and Timing B Out connectors. If you attach equipment to
the Timing A Out or Timing B Out connector, you normally attach it to a node with line mode
because equipment near the external timing reference can be directly wired to the reference.
•
NE Reference—Allows you to define three timing references (Ref 1, Ref 2, Ref 3). The node uses
Reference 1 unless a failure occurs to that reference, in which case the node uses Reference 2. If
Reference 2 fails the node uses Reference 3, which is typically set to Internal Clock. The internal
clock is the SETS clock provided on the TCC2/TCC2P. The options displayed depend on the Timing
Mode setting.
– Timing Mode set to External—Your options are BITS-1, BITS-2, and Internal Clock.
–
Timing Mode set to Line—Your options are the node’s working STM-N cards (non-DWDM
nodes), or OSC cards (DWDM nodes) and Internal Clock. Select the cards/ports that are directly
or indirectly connected to the node wired to the building integrated timing supply (BITS)
source, that is, select the node’s trunk cards. Set Reference 1 to the trunk card that is closest to
the BITS source. For example, if Slot 5 is connected to the node wired to the BITS source, select
Slot 5 as Reference 1.
– Timing Mode set to Mixed—Both BITS and optical cards are available, allowing you to set a
mixture of external BITS and optical trunk (span) cards as timing references.
•
BITS-1 Out/BITS-2 Out—Define the timing references for equipment connected to the Timing A
Out or Timing B Out FMEC connector. Normally, Timing Out is used with line nodes, so the options
displayed are the working optical cards. Timing A Out and Timing B Out are enabled as soon as
BITS-1 and BITS-2 facilities are placed in service.
Step 4
Click Apply .
Step 5
Click the BITS Facilities subtab.
Note
The BITS Facilities section sets the parameters for your BITS-1 and BITS-2 timing references.
Many of these settings are determined by the timing source manufacturer. If equipment is timed
through BITS Out, you can set timing parameters to meet the requirements of the equipment.
Step 6
In the BITS In area, complete the following information:
•
Facility Type—Choose E1 or 2 MHz depending on the signal supported in your market. E1 and
2 MHz are physical signal modes used to transmit the external clock (from a global positioning
satellite [GPS], for example) to BITS.
•
BITS In State—If Timing Mode is set to External or Mixed, set the BITS In State for BITS-1 and/or
BITS-2 to
unlocked depending whether the Timing A Out or Timing B Out connectors on the
MIC-C/T/P FMEC are connected to the external timing source. If Timing Mode is set to Line, set
the BITS In State to
locked .
Step 7 If the BITS In State for BITS-1 and BITS-2 is set to locked , continue with Step 8 . If the BITS In State
is set to unlocked for either BITS-1 or BITS-2, complete the following information:
•
Coding—Choose the coding used by your BITS reference, either HDB3 or AMI (alternate mark
inversion). If you selected 2 MHz, the coding option is disabled.