Table 3-5 Ssm Generation 2 Message Set - Cisco ONS 15327 User Documentation

Chapter 3 Node Setup
Table 3-4
Message
ST3
SMC
ST4
DUS
RES
Table 3-5
Message
PRS
STU
ST2
TNC
ST3E
ST3
SMC
ST4
DUS
RES
Procedure: Set Up ONS 15327 Timing
From the CTC node view, click the Provisioning > Timing tabs
Step 1
In the General Timing section, complete the following information:
Step 2
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June 2002
SSM Generation 1 Message Set (continued)
Quality Description
4 Stratum 3
5 SONET minimum clock
6 Stratum 4
7 Do not use for timing synchronization
Reserved; quality level set by user
SSM Generation 2 Message Set
Quality Description
1 Primary reference source - Stratum 1
2 Sync traceability unknown
3 Stratum 2
4 Transit node clock
5 Stratum 3E
6 Stratum 3
7 SONET minimum clock
8 Stratum 4
9 Do not use for timing synchronization
Reserved; quality level set by user
Timing Mode—Set to External if the ONS 15327 derives its timing from a BITS source wired to the
BITS port on the MIC; set to Line if timing is derived from an OC-N card that is optically connected
to the timing node. A third option, Mixed, allows you to set external and line timing references.
(Because Mixed timing may cause timing loops, Cisco does not recommend its use. Use this mode
with care.)
SSM Message Set—Choose the message set level supported by your network. If a Generation 1 node
receives a Generation 2 message, the message will be mapped down to the next available Generation
1. For example, an ST3E message becomes an ST3.
Quality of RES—If your timing source supports the reserved S1 byte, you set the timing quality here.
(Most timing sources do not use RES.) Qualities are displayed in descending quality order as ranges.
For example, ST3<RES<ST2 means the timing reference is higher than a Stratum 3 and lower than
a Stratum 2. See Table 3-4
Revertive—If checked, the ONS 15327 reverts to a primary reference source after the conditions that
caused it to switch to a secondary timing reference are corrected.
Revertive Time—If Revertive is checked, indicate the amount of time the ONS 15327 will wait
before reverting back to its primary timing source.
and Table 3-5 for more information.
Cisco ONS 15327 User Documentation, R3.3
Setting Up ONS 15327 Timing
(Figure 3-5).
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