Cisco ONS 15327 Procedure Manual page 124

NTP-B28 Set Up Timing
Note
State—For line-timed nodes with no equipment timed through BITS Out, set State to OOS (Out of
•
Service). For nodes using external timing or line timing with equipment timed through BITS Out,
set the state to IS (In Service).
Step 4 If the state is set to OOS, continue with
information:
• Coding—Choose the coding used by your BITS reference, either B8ZS or AMI.
Framing—Choose the framing used by your BITS reference, either ESF (Extended Super Frame, or
•
SF (D4) (Super Frame).
Sync Messaging—Check this check box to enable SSM. SSM is not available if Framing is set to
•
Super Frame.
• AIS Threshold—If SSM is disabled or Super Frame is used, choose the quality level where a node
sends an alarm indication signal (AIS) from the BITS 1 Out and BITS 2 Out backplane pins. An AIS
alarm is raised when the optical source for the BITS reference falls to or below the SSM quality level
defined in this field.
LBO—If you are timing an external device connected to the BITS Out pins, choose the distance
•
between the device and the ONS 15327. Options are: 0-133 ft. (default), 124-266 ft., 267-399 ft.,
400-533 ft., and 534-655 ft.
Under Reference Lists, complete the following information:
Step 5
Note
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 Stratum 3 clock provided on the XTC. The options displayed depend on the Timing
Mode setting.
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–
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BITS 1 Out/BITS 2 Out—Define the timing references for equipment wired to the BITS Out
•
connections on the MIC. Normally, BITS Out is used with line-timed nodes, so the options displayed
are the working OC-N cards. BITS 1 and BITS 2 Out are enabled when BITS-1 and BITS-2 facilities
are placed in service.
Cisco ONS 15327 Procedure Guide, R4.0
3-18
The BITS Facilities section sets the parameters for your BITS1 and BITS2 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.
You can 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 that can be attached to the
node's BITS Out connections on the MIC. If you attach equipment to BITS Out connections, you
normally attach it to a node with Line mode because equipment near the external timing
reference can be directly wired to the reference.
If the Timing Mode is set to External, your options are BITS1, BITS2, and Internal Clock.
If the Timing Mode is set to Line, your options are the node's working OC-N cards and Internal
Clock. Choose the cards/ports that are directly or indirectly connected to the node wired to the
BITS source, that is, the node's trunk (span) 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, choose Slot 5 as Reference 1.
If the Timing Mode is set to Mixed, both BITS and OC-N cards are available, allowing you to
set a mixture of external BITS and OC-N trunk (span) cards as timing references.
Step 5. If the state is set to IS, complete the following
Chapter 3 Turn Up Node
March 2003