Cryptography, the study of hidden information

April 16, 2020

Crypto means hidden or secret from the original Greek word Kryptos. Mainly the cryptography is the study of the secret of hidden information technique for the secure communication of two parties from the prevention of the third party to listen. The study of cryptography is about the prevention of third-party protocols and to secure the documents properly with authentication. Some disciplines like Mathematics, physics, computer science, electrical science, communication science are interrelated with modern cryptography. Cryptography is similar to the modern age word encryption which is the lack of coherent meaning in the state of communication. The predecessor of the encrypted information shares the deciphering technique. To have the secret conversation of sharing information may search over which provides a better service.

The Rotor machine:

The Rotor machine is nothing but an electro-mechanical device combined with a plain text stream cipher to encrypt and decrypt the information. In the 1920’s to the 1970’s the rotor, the machine was in the widespread usage in the cryptographic state of the art. Drums or wheels are used in the rotor to connect the electrical contacts and it is known to be the primary component of the rotor. A fixed substitution of letters helps to replace the encryption with the wiring contact between the implements. The encryption of letters leads to the substitution of the positions and with its small security. With the change of every keypress, the rotor machine produces the multiple substitutions of the alphabets.

Background of cryptography:

In the earlier days of the cryptography usage, only the simple substitution cipher is used with some secret scheme. A simple substitution cipher is nothing but the simple replacement of the text or replacement of letters. For the single replacement scheme, a monoalphabetic substitution cipher is used which known to be the single letter replacement scheme. The monoalphabetic substitution cipher is easily broken because of the frequent usage. Multiple substitution alphabets are known to be a polyalphabetic cipher and are some more secure than the monoalphabetic cipher. The study of frequent use of text is known as frequency analysis. In a monoalphabetic substitution cipher, the unique letter patterns are used in other languages too. The very frequent usage of letters in the English language is the plaintext letters E, T, A, I, O, N and S are easy to be identified as in ciphertext. Encryption of the plaintext is known to be the ciphertext. Different substitution for the plaintext is handled in various ways by the cryptographers for many years. This was the failed usage to hide the text fully. So, the scheme was demolished in the 16th century.

Combined cipher machine:

During world war II, a common cipher machine was used to secure allied communication. In the year 1942, the approval for the combined cipher machine was granted and the production was started after a couple of months. The United States produced the resources of the combined cipher machine when British don’t have any source for the production. Don Seiler was the inventor of the adopter. From 1 November 1943, the combined cipher machine was used for the small-scale naval usage and from April 1944, it was used in the operational use of the armed services of the United States and the United Kingdom.