Military communications are highly dependent on satellites, especially for tactical applications. Similarly, many commercial applications require mobile satellite terminals to maintain operations in remote areas. Mobile satellite communications terminals have to be rugged and reliable, so the computers installed in them must also exhibit these qualities. Limited space is an additional constraint for any mobile application, as are power supply fluctuations and dropouts. Putting all these constraints together dictates high power computers with small volume, high reliability, rugged and with built in uninterruptable power supplies.