The Athens International Airport (AIA), so-called “Eleftherios Venizelos” is the largest and busiest international airport in Greece which serves its capital, the city of Athens, and Attica region, located 30 km (19 miles) east of Athens. Athens International Airport is a member of Group 1 of the Airports Council International supporting over 25 million passengers annually and in fact, it hosts more than 370 companies with more than 16.000 employees servicing approximately 100.000 passengers and 800 flights per day during peak periods. Furthermore, Athens International Airport consists of two passenger terminals, the “Main Terminal” and the “Satellite” Terminal which are connected through an underground link as well as Athens Airport is connected with road and rail transport to support passengers’ traffic and cargo movement. Finally, apart from life-critical systems, airports are business-critical as they must operate efficiently 24/7 in order to process and support all these passengers and cargo transport services and respective supporting operations.