6-3
Cisco ONS 15310-MA SDH Reference Manual, Release 9.1 and Release 9.2
78-19417-01
Chapter 6 Timing
Synchronization Status Messaging
If you enable SSM for the ONS 15310-MA SDH, consult your timing reference documentation to
determine which message set to use. Table 6-1 and Table 6-2 show the Generation 1 and Generation 2
message sets.
Table 6-1 SSM Message Set
Message Quality Description
G811 1 Primary reference clock
STU 2 Sync traceability unknown
G812T 3 Transit node clock traceable
G812L 4 Local node clock traceable
SETS 5 Synchronous equipment
DUS 6 Do not use for timing synchronization
Table 6-2 SSM Generation 2 Message Set
Message Quality Description
PRC 1 Primary reference source—Stratum 1
STU 2 Synchronization traceability unknown
ST2 3 Stratum 2
TNC 4 Transit node clock
G.813E 5 Stratum 3E
G.813 6 PRC
SMC 7 SDH minimum clock
ST4 8 Stratum 4
DUS 9 Do not use for timing synchronization
RES Reserved; quality level set by user
