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quality-level (Clock Synchronization)


Hierarchy Level


Configure the quality level for a timing source so that the router knows the best available source with which to synchronize. The quality level specifies the accuracy level of the clock and is transmitted across the network through Synchronization Status Messages (SSMs) over the Ethernet Synchronization Messaging Channel (ESMC), or through SSMs contained in SONET/SDH frames.

SONET SSM messages are either Generation 1 or Generation 2. Generation 1 is the first and most widely deployed SSM message set. Generation 2 is a newer version. Quality level options are available for both Generation 1 and Generation 2.


prs—Primary reference source—Stratum 1

st2—Stratum 2

tnc—Transit node clock

st3e—Stratum 3E

st3—Stratum 3

smc—SONET minimum clock

st4—Stratum 4

prc—Primary reference clock

ssu-a—Synchronization supply unit A

ssu-b—Synchronization supply unit B

sec—SDH equipment clock

Required Privilege Level

interface—To view this statement in the configuration.

interface-control—To add this statement to the configuration.

Release Information

Statement introduced in Junos OS Release 11.2R4.