![]() Cryptography's potential for use as a tool for espionage and sedition has led many governments to classify it as a weapon and to limit or even prohibit its use and export. The growth of cryptographic technology has raised a number of legal issues in the Information Age. Information-theoretically secure schemes that provably cannot be broken even with unlimited computing power, such as the one-time pad, are much more difficult to use in practice than the best theoretically breakable, but computationally secure, schemes. Such schemes, if well designed, are therefore termed "computationally secure" theoretical advances (e.g., improvements in integer factorization algorithms) and faster computing technology require these designs to be continually reevaluated, and if necessary, adapted. While it is theoretically possible to break into a well-designed system, it is infeasible in actual practice to do so. Modern cryptography is heavily based on mathematical theory and computer science practice cryptographic algorithms are designed around computational hardness assumptions, making such algorithms hard to break in actual practice by any adversary. Since the development of rotor cipher machines in World War I and the advent of computers in World War II, cryptography methods have become increasingly complex and their applications more varied. The cryptography literature often uses the names "Alice" (or "A") for the sender, "Bob" (or "B") for the intended recipient, and "Eve" (or "E") for the eavesdropping adversary. The sender of an encrypted (coded) message shares the decryption (decoding) technique only with intended recipients to preclude access from adversaries. Practical applications of cryptography include electronic commerce, chip-based payment cards, digital currencies, computer passwords, and military communications.Ĭryptography prior to the modern age was effectively synonymous with encryption, converting readable information ( plaintext) to unintelligible nonsense text ( ciphertext), which can only be read by reversing the process ( decryption). ![]() Core concepts related to information security ( data confidentiality, data integrity, authentication, and non-repudiation) are also central to cryptography. Modern cryptography exists at the intersection of the disciplines of mathematics, computer science, information security, electrical engineering, digital signal processing, physics, and others. ![]() More generally, cryptography is about constructing and analyzing protocols that prevent third parties or the public from reading private messages. Lorenz cipher machine, used in World War II to encrypt communications of the German High CommandĬryptography, or cryptology (from Ancient Greek: κρυπτός, romanized: kryptós "hidden, secret" and γράφειν graphein, "to write", or -λογία -logia, "study", respectively ), is the practice and study of techniques for secure communication in the presence of adversarial behavior.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |