Password is used as a means of protection information, and has experienced three development periods. It earlier in military and diplomatic areas, gradually entering people's lives with the development of technology.
In the manual phase, people only need to encrypt characters through paper and pen. The historical source of cryptography is long, and the use of human beings can be traced back to the era of Cuba Babylon. The Phaistos disc of the figure below is a clay disc that has a diameter of about 160 mm, which begins in the 17th century BC, and the surface has a clear letter. In recent years, studies have considered it to record some ancient astronomical calendar, but the truth is still a fan.
With the rise of the industrial revolution, cryptography has also entered the machine era, electronic age. Compared to human hand operations compared to electronic cryptography uses a better complex encryption method, but also has higher encryption decryption efficiency. The most representative of which is the enigma shown below.
ENIGMA is an encrypted electronics invented in 1919 in 1919, which proved to be one of the most reliable encryption systems in history. During the World War II, it began to be used by the Germans for railways, in the enterprise, and the German confidential communication technology is in a leading position. Although the encryption equipment has made great progress during this period, the theory of cryptography has not changed, and the main means of encryption is still - alternative and transposition.
The appearance of the computer makes the password to highly complex operations. Until 1976, in order to adapt to the public key password theory generated by computer network communication and business confidentiality requirements, cryptography has achieved a major breakthrough in real sense, and entered the modern cryptography stage. Modern cryptography changes the classical cryptography single encryption method, integrating a lot of knowledge, geometrical, algebra, etc., making cryptography more flourishing.
In the present, countries around the world have attached great importance to the study of passwords, and have evolved to modern cryptography. Cipher has become a comprehensive science that combines multiple major sciences such as physical, quantum mechanics, electronics, and linguistics. As "quantum password", "chaotic password" and other advanced theories, which plays a very important role in information security.
Next, some interesting classical encryption methods will be described.
