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Network Reliability and Security
Published in Partha Pratim Sahu, Advances in Optical Networks and Components, 2020
Both active wiretapping and passive wiretapping require different protection mechanisms. The passive attacks of message contents and traffic usually cannot be detected but those are required to be prevented. The attacks of message stream modification, denial of message service and message playbacks cannot be debarred. Secure communications are dependent on the cryptography technique to protect the confidentiality and integrity of messages transmitted between machines. Cryptography is derived from the Greek word “kryptos”, which means “hidden” and from graphy, which means “to write”, and it is the science of secret communication. The original message is cleartext and the transformed message is known as ciphertext, which is also sometimes called a cryptogram. Initially, military and intelligence organizations have used some cryptographic techniques to keep the message sensitive and secret over the years. The message-encoding methodology was first reported by Julius Caesar [2] when sending messages. The process of changing plaintext to ciphertext is called enciphering or encryption. The inverse operation converting ciphertext to plaintext is known as deciphering or decryption.
Review of Security Methods Based on Classical Cryptography and Quantum Cryptography
Published in Cybernetics and Systems, 2023
Shalini Subramani, Selvi M, Kannan A, Santhosh Kumar Svn
It constructs a quantum channel to require pair of polarization of photons they are the two types of polarization are rectilinear and diagonal. In rectilinear, there are two orientations namely horizontal orientation and vertical orientation whereas the diagonals are around 45 and 135 degrees of orientation in a polarized photon. The classical bits that are polarized in photons are measured only in 0 bits or 1 bits (Tsurumaru and Hayashi 2013). The cryptography is sharing the keys between Gracie and Jack through photons and optical fiber communication between the computers. The extensive nature of encryption algorithm produces the cipher text C from the plain text message T is contributing into a cryptogram, A. Gracie generates the cryptogram using the key S using the formula shown in Equation (1).
A block encryption algorithm based on exponentiation transform
Published in Cogent Engineering, 2020
Nursulu Kapalova, Ardabek Khompysh, Müslüm Arici, Kunbolat Algazy
A comprehensive solution to the problems of protecting electronic information can only be obtained with cryptographic methods that allow solving the most important problems of secure automated processing and data transfer. Cryptographic methods of information protection are special methods of encryption, coding, or other transformation of information that makes the content inaccessible unless a cryptogram key and inverse transformation are presented (Chipiga, 2009). The cryptographic information protection facility has become the main tool to protect data from unauthorized access. Today in the world, in connection with the active growth of digital technologies, the branches of science associated with cryptographic methods of information protection are rapidly developing. Papers (Chengqing et al., 2019; Liu et al., 2018; Ullah et al., 2018; Xiong et al., 2018a) describe these issues in detail, the authors carried out colossal work to review scientific articles on the cryptographic protection of information, including encryption algorithms designed to protect the information in the form of images. In some other works, the authors considered several encryption algorithms and the results of cryptographic attacks against them (Li et al., 2017, 2018; Xiong et al., 2018b).