The concept of election verifiability through cryptographic solutions has emerged in the academic literature to introduce transparency and trust in electronic voting systems.

The red / black concept refers to the careful segregation in cryptographic systems of signals that contain sensitive or classified plaintext information ( red signals ) from those that carry encrypted information, or ciphertext ( black signals ).

* Zero-knowledge, a cryptographic proof concept

Dembski appeals to cryptographic practice in support of the concept of the universal probability bound, noting that cryptographers have sometimes compared the security of encryption algorithms against brute force attacks by the likelihood of success of an adversary utilizing computational resources bounded by very large physical constraints.

This benefit has contributed to its popularity in cryptographic software.

Even though the goal has been the same, the methods and techniques of cryptanalysis have changed drastically through the history of cryptography, adapting to increasing cryptographic complexity, ranging from the pen-and-paper methods of the past, through machines like Bombes and Colossus computers at Bletchley Park in World War II, to the mathematically advanced computerized schemes of the present.

In light of this, and the practical difficulty of managing such long keys, modern cryptographic practice has discarded the notion of perfect secrecy as a requirement for encryption, and instead focuses on computational security, under which the computational requirements of breaking an encrypted text must be infeasible for an attacker.

Information that has been encrypted ( rendered unusable ) can be transformed back into its original usable form by an authorized user, who possesses the cryptographic key, through the process of decryption.

Each user has a pair of cryptographic keys-a public encryption key and a private decryption key.

It has been proven that applying Grover's algorithm to break a symmetric ( secret key ) algorithm by brute force requires roughly 2 < sup > n / 2 </ sup > invocations of the underlying cryptographic algorithm, compared with roughly 2 < sup > n </ sup > in the classical case, meaning that symmetric key lengths are effectively halved: AES-256 would have the same security against an attack using Grover's algorithm that AES-128 has against classical brute-force search ( see Key size ).

A variant of Mersenne Twister has been proposed as a cryptographic cipher.

A pair of cryptographic stream ciphers based on output from Mersenne twister has been proposed by Makoto Matsumoto et al.

In a computer data context, cryptographic methods have been developed ( see digital signature and challenge-response authentication ) which are currently not spoofable if and only if the originator's key has not been compromised.

The problem of how to safely generate truly random keys is difficult, and has been addressed in many ways by various cryptographic systems.

Throughout the lifetime of CC, it has not been universally adopted even by the creator nations, with, in particular, cryptographic approvals being handled separately, such as by the Canadian / US implementation of FIPS-140, and the CESG Assisted Products Scheme ( CAPS )

In the case of full disk encryption applications, especially when implemented without a boot PIN, a cryptoprocessor would not be secure against a cold boot attack if data remanence could be exploited to dump memory contents after the operating system has retrieved the cryptographic keys from its TPM.

block cipher has negligible cryptographic security, so the Pearson hash function is not cryptographically strong ; but it offers these benefits:

Plaintext has reference to the operation of cryptographic algorithms, usually encryption algorithms, and is the input upon which they operate.

It has been a useful source for simulations, modeling, and even for deriving the arbitrary constants in cryptographic algorithms to demonstrate that the constants had not been selected for ( in B. Schneier ’ s words ) " nefarious purpose ( es ).

Friedman has the distinction of having one of the longest known suppressed patent applications, for, a patent for a " cryptographic system ".

He has worked with others, including Bruce Schneier, designing cryptographic algorithms, testing algorithms and protocols, and writing papers and books.

* Replay attack, in cryptography, an attack where an adversary interferes with a cryptographic protocol by inserting ( a part of ) a message that has been sent previously in a protocol run

However, no cryptographic module has ever been found to be signed by _NSAKEY and Microsoft denies that any other certification authority exists.

Intel's hyperthreading implementation has a vulnerability through which it is possible for one application to steal a cryptographic key from another application running in the same processor by monitoring its cache use.

Biham has taken part in the design of several new cryptographic primitives:

The ideal cryptographic hash function has four main or significant properties:

Bletchley Park is mainly remembered for breaking messages enciphered on the German Enigma cypher machine, but its greatest cryptographic achievement may have been the breaking of the German on-line teleprinter Lorenz cipher ( known at GC & CS as Tunny ).

Recently, a large number of cryptographic primitives based on bilinear mappings on various elliptic curve groups, such as the Weil and Tate pairings, have been introduced.

Those same machines had been used during World War II for cryptographic statistical processing.

After the War, interrogation of German cryptographic personnel led to the conclusion that German cryptanalysts understood that cryptanalytic attacks against Enigma were possible, but they had been thought to require impracticable amounts of effort and investment.

A wide variety of cryptographic authentication schemes and protocols have been developed to provide authenticated key agreement to prevent man-in-the-middle and related attacks.

Common methods for verifying that operating system patches have not been altered include the use of cryptographic hash, such as an MD5 based checksum, or the use of read-only media.

Since Dee is well-known to have been a spy for Elizabeth I's court, there are many modern interpretations of his Angelic manuscripts as cryptographic documents-most likely polyalphabetic ciphers-designed to disguise political messages ( see for instance, Langford This aspect of the manuscripts is not of major concern to Enochian magicians, but there is no doubt that Dee's knowledge of mathematics and sophisticated cipher systems contributed extensively to his magical system.

Extensions of the π-calculus, such as the spi calculus and applied π, have been successful in reasoning about cryptographic protocols.

There is a long list of cryptographic hash functions, although many have been found to be vulnerable and should not be used.

The National Institute of Standards and Technology ( NIST ), wrote in a 2009 survey: " There are viable alternatives for both public key encryption and signatures that are not vulnerable to Shor ’ s Algorithm ” and “ Of the various lattice based cryptographic schemes that have been developed, the NTRU family of cryptographic algorithms appears to be the most practical ... smallest key size ... highest performance.

AES is available in many different encryption packages, and is the first publicly accessible and open cipher approved by the National Security Agency ( NSA ) for top secret information when used in an NSA approved cryptographic module ( see Security of AES, below ).

Block ciphers are important elementary components in the design of many cryptographic protocols, and are widely used to implement encryption of bulk data.

However, block ciphers may also be used as building blocks in other cryptographic protocols, such as universal hash functions and pseudo-random number generators.

Cryptanalysis is used to defeat cryptographic security systems and gain access to the contents of encrypted messages, even if the cryptographic key is unknown.

In cryptography, key size or key length is the size measured in bits of the key used in a cryptographic algorithm ( such as a cipher ).

As each of these is of a different level of cryptographic complexity, it is usual to have different key sizes for the same level of security, depending upon the algorithm used.

Whatever strategy is used ( simple or mutual ), the level of protection strongly depends on the correctness of the implementation of the web browser and the server software and the actual cryptographic algorithms supported.

In cryptographic hash functions, a Merkle – Damgård construction is usually used.

However, as in any other cryptographic system, care must be used to correctly apply even information-theoretically secure methods ; the Venona project was able to crack the one-time pads of the Soviet Union due to their improper reuse of key material.

The measure of sufficient randomness in extractors is min-entropy, a value related to Shannon entropy through Rényi entropy ; Rényi entropy is also used in evaluating randomness in cryptographic systems.

The most difficult integers to factor in practice using existing algorithms are those that are products of two large primes of similar size, and for this reason these are the integers used in cryptographic applications.

Any cryptographic hash function, such as MD5 or SHA-1, may be used in the calculation of an HMAC ; the resulting MAC algorithm is termed HMAC-MD5 or HMAC-SHA1 accordingly.

The cryptographic strength of the HMAC depends upon the size of the secret key that is used.

In cryptography, oracles are used to make arguments for the security of cryptographic protocols where a hash function is used.

The cryptographic security of PGP encryption depends on the assumption that the algorithms used are unbreakable by direct cryptanalysis with current equipment and techniques.

As current versions of PGP have added additional encryption algorithms, the degree of their cryptographic vulnerability varies with the algorithm used.

It is an approach used by many cryptographic algorithms and cryptosystems.

These characteristics can be used to construct many other ( sometimes surprising ) cryptographic protocols and applications, such as digital cash, password-authenticated key agreement, multi-party key agreement, time-stamping services, non-repudiation protocols, etc.

Passwords that are used to generate cryptographic keys ( e. g., for disk encryption or Wi-Fi security ) can also be subjected to high rate guessing.

MD5 and SHA1 are frequently used cryptographic hash functions but they are not recommended for password hashing unless they are used as part of a larger construction such as in PBKDF2.

* Plaintext, most commonly used in a cryptographic context