EXFO FTB-8100 Series Transport Blazer for FTB-500 - Manual (Page 435)

Advanced Tabs
SONET/SDH Application 421
Service Disruption Time (SDT) - Results
Service Disruption Time (SDT) - Results
Note: The SDT - Results tab is available with Multi-Channel SDT test mode.
The Service Disruption Time (SDT) corresponds to the time during which
there is a disruption of service due to the network switching from the
active channels to the backup channels or vice versa.
Press TEST, SDT and Results.
Note: Stopping the SDT test will stop the measurement process without clearing
the results. However, starting the test again while the STD is still On
(enabled) will reset the results.
Note: When the measured disruption is equal or longer than the Test Period, then
the disruption time equals the Test Period time.