In the current revolution of IC and microelectronics design, large number of logic elements can be put on a single chip die. No. of transistors can reach now more than 10 million transistors which enables designers to put large systems on a single chip. This progress, in turns, lead to the introduction of new design methodologies and techniques. This technology is called System-on-Chip "SoC" that uses different design blocks made by several designers. These designs should be resuable ones so as to reduce the time needed to devlope the same functionality again by other group.