Another unique feature of telemetry systems is autonomy. Spacecraft require the ability to monitor their internal functions and act on information without ground control interaction. The need for autonomy originates from problems such as insufficient ground coverage, communication geometry, being too near the Earth-Sun line (where solar noise interferes with radio frequencies), or simply for security purposes. Autonomy is important so that the telemetry system already has the capability to monitor the spacecraft functions and the command systems have the ability to give the necessary commands to reconfigure based on the needs of the action to be taken. There are three steps to this process: