The two objects cdot3OamErrSymPeriodWindowHi and
cdot3OamErrSymPeriodLo together form an unsigned 64-bit
integer representing the number of symbols over which this
threshold event is defined. This is defined as
cdot3OamErrSymPeriodWindow = ((2^32)*cdot3OamErrSymPeriodWindowHi)
+ cdot3OamErrSymPeriodWindowLo
If cdot3OamErrSymPeriodThreshold symbol errors occur within a
window of cdot3OamErrSymPeriodWindow symbols, an Event
Notification OAMPDU should be generated with an Errored Symbol
Period Event TLV indicating the threshold has been crossed in
this window.
The default value for cdot3OamErrSymPeriodWindow is the number
of symbols in one second for the underlying physical layer.