This reports how long, in seconds, this security association has been active since it was established. Comparing this against ntqVPNMaxLifetime tells an admin how close the SA is to its configured rekey or expiration point, which is useful when diagnosing a tunnel that drops and re-establishes on a regular cycle. An SA showing ntqVPNLifetime near its ntqVPNMaxLifetime value is about to expire and should shortly transition to the dying state as it rekeys.