This paper was to analyze different data centers from design and function perspectives and develop a prototype of a data center for maximum efficiency. Relevant data on the designs and functions of several data centers as well as their advantages were gathered from various sources and analyzed. This is compared and summarized in this work. Finally, an architectural model of an efficient data center is developed. The proposed data center adopts several functions such as Virtualization, monitoring systems, Green IT, and dark strategy. These functions are expected to maximize efficiency, availability and agility, and reduce power consumption, space requirement, and cost of operations and staff salary.