This allows for more flexibility in the scheduling of maintenance to minimize aircraft downtime. The employees experience 60 minutes of unscheduled downtime. This results in less downtime and less disruption to business critical systems. The opposite of downtime is uptime. Uptime is the opposite of downtime. A distinction can be made between scheduled and unscheduled downtime. The report stated that Linux servers had less unplanned downtime than Windows 2000 servers. It includes active preventive and corrective maintenance downtime. It excludes logistics time, waiting or administrative downtime, and preventive maintenance downtime. Twitter had approximately ninety-eight percent uptime in 2007 (or about six full days of downtime). Chemical cleaning products have been developed to remove and prevent struvite with minimal downtime. It excludes logistics time and waiting or administrative downtime. The new trains are lighter to reduce the amount of wear and downtime. In 2007, the system received funding to improve efficiency by reducing this vehicle downtime. A resilient SD-WAN reduces network downtime.