T-VIPS CP525 cMux, User Manual

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Functional Description 49
ID: um_tsmux CP525 cMux User’s Manual Rev. 5.20.12 (3944)
wait auto
wait_confirm
switch criteria met
confirm_timeout > 0
confirm_timeout expired, switch criteria still met
=> DO SWITCH!
confirm_timeout expired,
switch criteria not met
switch_timeout expired
switch criteria met
confirm_timeout = 0
=> DO SWITCH!
switch criteria changed
=> UPDATE TIMEOUT
Figure 5.16 Service fallback switch controller state machine
Both the
confirm_time
and
switch_timeout
can be individually configured for each service
switcher.
The state of the switch controller (including timing information) is available in the GUI.
5.14.2 Details on confirm timeout handling
The
confirm_time
is configured for each severity level. I.e. a confirmation time for “critical”
main input level can be set lower than for “major” and so on.
For example, 5 seconds may be configured for the “critical” state while 20 seconds may be
configured for the “major” state.
A special case deserves more explanation: multiple alarms, with different severity levels, during
the
wait_confirm
state. The controller is designed so that it will not “stay forever” in the
wait_confirm
state and will respond to the most critical alarm.
The controller has separate timers for each severity level, and each timer has an independently
configured
confirm_time
. When an alarm event is detected the timer for that alarm level
will be started and the switch will enter the
wait_confirm
state. When the timer reaches the
confirm_time
then the controller will perform a switch and enter the wait state. If, whilst the
switch is in the
wait_confirm
state, a second alarm event occurs with a different alarm level
then the timer for that alarm level will be started and will run “in parallel” with the timer for
the first alarm event. There is then a “race” between timers and in this case the first timer to
reach its
confirm_time
will cause the controller to perform a switch and enter the wait state
at which point all alarm timers are reset.