The discovery of algorithms that could produce public / private key pairs revolutionized the practice of cryptography, beginning in the mid-1970s.

Strong cryptography network protocols such as Secure Sockets Layer, I2P, and virtual private networks obscure the data transferred using them.

Secret-key ( symmetric ) cryptography requires the initial exchange of a shared key in a manner that is private and integrity-assured.

The man-in-the-middle attack ( often abbreviated MITM, MitM, MIM, MiM, also known as a bucket brigade attack, or sometimes Janus attack ) in cryptography and computer security is a form of active eavesdropping in which the attacker makes independent connections with the victims and relays messages between them, making them believe that they are talking directly to each other over a private connection, when in fact the entire conversation is controlled by the attacker.

During the War, Arlington Hall was in many respects similar to Bletchley Park in England, only one of two primary cryptography operations in Washington ( the other was the Naval Communications Annex, also housed in a commandeered private girls ' school ).

Once the user gets the key they ( and only they ) can unblind it and retrieve their full private key, after which point the system becomes the same as identity based cryptography.

This means that the user ( Bob ) cannot decrypt it without a currently valid certificate and also that the certificate authority cannot decrypt the message as they don't have the user's private key ( i. e., there is no implicit escrow as with ID-based cryptography, as the double encryption means they cannot decrypt it solely with the information they have ).

For example, Freenet, I2P and Tor hidden services implement censorship-resistant URLs based on public-key cryptography: only a person having the correct private key can update the URL or take it down.

Public / private key pairs used in asymmetric encryption ( public key cryptography ) must be much longer than 128 bits for security ; see key size for more details.

In public key cryptography an individual is able to generate a key pair, where one of the keys is kept private

Similar problems arise in cryptography, where private keys are often generated using such a generator.

* Public / private key-in public key cryptography, separate keys are used to encrypt and decrypt a message.

In an authenticated key-agreement protocol that uses public key cryptography, perfect forward secrecy ( or PFS ) is the property that ensures that a session key derived from a set of long-term public and private keys will not be compromised if one of the ( long-term ) private keys is compromised in the future.

For instance, the United States has defined cryptographic products as munitions since World War II and has prohibited export of cryptography beyond a certain ' strength ' ( measured in part by key size ), and Russia banned its use by private individuals in 1995 .< ref > It is not clear if the Russian ban is still in effect.

There are now many active academic cryptologists, mathematics departments with strong programs in cryptography, and commercial information security companies and consultants.

In cryptography, encryption is the process of transforming information ( referred to as plaintext ) using an algorithm ( called a cipher ) to make it unreadable to anyone except those possessing special knowledge, usually referred to as a key.

The result of the process is information ( in cryptography, referred to as ciphertext ).

The Communications-Electronics Security Group ( CESG ) of GCHQ provides assistance to government departments on their own communications security: CESG is the UK national technical authority for information assurance, including cryptography.

Concepts, methods and results from coding theory and information theory are widely used in cryptography and cryptanalysis.

Information security uses cryptography to transform usable information into a form that renders it unusable by anyone other than an authorized user ; this process is called encryption.

* Key ( cryptography ), a piece of information that controls the operation of a cryptography algorithm

# All mathematical aspects of computer science, including complexity theory, logic of programming languages, analysis of algorithms, cryptography, computer vision, pattern recognition, information processing and modelling of intelligence.

The National Security Agency ( NSA ) is a cryptologic intelligence agency of the United States Department of Defense responsible for the collection and analysis of foreign communications and foreign signals intelligence, as well as protecting U. S. government communications and information systems, which involves information security and cryptanalysis / cryptography.

Imperfect cloning can be used as an eavesdropping attack on quantum cryptography protocols, among other uses in quantum information science.

Primes are used in several routines in information technology, such as public-key cryptography, which makes use of properties such as the difficulty of factoring large numbers into their prime factors.

Efforts are being made to more fully develop quantum cryptography, which will theoretically allow guaranteed secure transmission of information.

In cryptography, a Type 1 product is a device or system certified by the National Security Agency ( NSA ) for use in cryptographically securing classified U. S. Government information.

In cryptography, Type 2 products are unclassified cryptographic equipment, assemblies, or components, endorsed by the National Security Agency ( NSA ), for use in telecommunications and automated information systems for the protection of national security information.

In cryptography, a key is a piece of information ( a parameter ) that determines the functional output of a cryptographic algorithm or cipher.

Some involve information in broader areas, such as secure communications, cryptography, intelligence operations and cooperation with third-parties.

In cryptography, plaintext is information a sender wishes to transmit to a receiver.

Such a detector is of interest for applications related to quantum information and quantum cryptography.

Cryptome is a website hosted in the United States since 1996 by independent scholars and architects John Young and Deborah Natsios that functions as a repository for information about freedom of speech, cryptography, spying, and surveillance.

In cryptography, a public key certificate ( also known as a digital certificate or identity certificate ) is an electronic document which uses a digital signature to bind a public key with an identity — information such as the name of a person or an organization, their address, and so forth.

Because of its more general utility, the remainder of this article will deal primarily with classical information, although quantum information theory does also have some potential applications ( quantum computing, quantum cryptography, quantum teleportation ) that are currently being actively explored by both theorists and experimentalists.

* Quantum cryptography protocol, a protocol for encrypting messages

* Socialist Millionaire Problem, a protocol in cryptography for two parties to verify the identity of the remote party through the use of a shared secret

In cryptography, a key-agreement protocol is a protocol whereby two or more parties can agree on a key in such a way that both influence the outcome.

* neural cryptography # Neural key exchange protocol

* Voice over Internet protocol ( VOIP ) vs. conventional telephony: Although conventional telephony systems are easily tapped and recorded, modern VOIP technology can employ low cost strong cryptography to evade surveillance.

It uses SSL / TLS to protect communications with web servers using strong cryptography when using the HTTPS protocol.

* 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

In cryptography, security ( engineering ) protocol notation is a way of expressing a protocol of correspondence between entities of a dynamic system, such as a computer network.

" Kak's three stage protocol " is a protocol for quantum cryptography suggested by Kak.

In cryptography, the Zimmermann – Sassaman key-signing protocol is a protocol to speed up the public key fingerprint verification part of a key signing party.

* Oblivious transfer, a type of cryptography protocol

In cryptography, a zero-knowledge proof or zero-knowledge protocol is an interactive method for one party to prove to another that a ( usually mathematical ) statement is true, without revealing anything other than the veracity of the statement.

In cryptography, an oblivious transfer protocol ( often abbreviated OT ) is a type of protocol in which a sender transfers one of potentially many pieces of information to a receiver, but remains oblivious as to what piece ( if any ) has been transferred.

In cryptography, Merkle's Puzzles is an early construction for a public-key cryptosystem, a protocol devised by Ralph Merkle in 1974 and published in 1978.

The FIREFLY protocol uses public key cryptography to exchange keys between two participants of a secured call.

In 1984, together with Charles H. Bennett, he invented the BB84 protocol for quantum cryptography.

* Zimmermann – Sassaman key-signing protocol, in cryptography