The date and time when the last complete path
was determined. A path is complete if responses
were received or timeout occurred for each hop on
the path; i.e., for each TTL value from the value
of the corresponding traceRouteCtlInitialTtl object
up to the end of the path or (if no reply from the
target IP address was received) up to the value of
the corresponding traceRouteCtlMaxTtl object.