The Aegis Weapon System represented a triumph of computer programming when it became operational in the early 1980s. It had five million lines of computer code, more than the Space Shuttle or even the super-secret B-2 bomber. The program also was reliable—as it had to be to defeat supersonic sea-skimming missiles.
Recent upgrades have increased the system's computing power. The current Baseline 6 upgrade alone adds 15 million lines of code while maintaining the system's reliability, which must grow even more to meet tomorrow's threats. Its aging mainframe computers, built to military specifications (MilSpecs), are saturated and remain frozen in time. Meanwhile, commercial off-the-shelf (COTS) equipment continues to advance according to Moore's Law, which states that the number of integrated circuits that can fit on a given-sized computer chip will double roughly every 18 months. The Aegis Program Office already is applying this burgeoning commercial processing power to perform new functions like theater ballistic missile defense.