Human societyis undergoing present one of the most profound changes throughout its existence, namely the transfer of ordinary activities in another room, so called Cyberspace, which removes borders, the concept of distance and brings flexibility, speed and efficiency. Currently access to information resources is done remotely, contracts are concluded between persons who do not meet face to face, electronic payments and funds transfer systems and electronic commerce is realized through networks, etc.. All these services and more hundreds of this type began to be a reality of the largest and most impressive medium for communication between people who became Internet. Cryptography is a branch of mathematics that deals with information security and authentication and restrict access to a computer system. It is a branch of science for protecting information by encrypting an unreadable format