In cryptography, key size or key length refers to the number of bits in a key used by a cryptographic algorithm.
Elliptic-curve cryptography (ECC) is an approach to public-key cryptography based on the algebraic structure of elliptic curves over finite fields. ECC allows smaller keys to provide equivalent security, compared to cryptosystems based on modular exponentiation in Galois fields, such as the RSA cryptosystem and ElGamal cryptosystem.
In cryptography, encryption is the process of transforming information in a way that, ideally, only authorized parties can decode. This process converts the original representation of the information, known as plaintext, into an alternative form known as ciphertext. Despite its goal, encryption does not itself prevent interference but denies the intelligible content to a would-be interceptor.
Communications security is the discipline of preventing unauthorized interceptors from accessing telecommunications in an intelligible form, while still delivering content to the intended recipients.
The U.S. National Security Agency (NSA) used to rank cryptographic products or algorithms by a certification called product types. Product types were defined in the National Information Assurance Glossary which used to define Type 1, 2, 3, and 4 products. The definitions of numeric type products have been removed from the government lexicon and are no longer used in government procurement efforts.
In computing, Internet Protocol Security (IPsec) is a secure network protocol suite that authenticates and encrypts packets of data to provide secure encrypted communication between two computers over an Internet Protocol network. It is used in virtual private networks (VPNs).
A digital signature is a mathematical scheme for verifying the authenticity of digital messages or documents. A valid digital signature on a message gives a recipient confidence that the message came from a sender known to the recipient.
_NSAKEY was a variable name discovered in Windows NT 4 SP5 in 1999 by Andrew D. Fernandes of Cryptonym Corporation. The variable contained a 1024-bit public key; such keys are used in public-key cryptography for encryption and authentication. Because of the name, however, it was speculated that the key would allow the United States National Security Agency (NSA) to subvert any Windows user's security. Microsoft denied the speculation and said that the key's name came from the fact that NSA was the technical review authority for U.S. cryptography export controls.
In cryptography, Camellia is a symmetric key block cipher with a block size of 128 bits and key sizes of 128, 192 and 256 bits. It was jointly developed by Mitsubishi Electric and NTT of Japan. The cipher has been approved for use by the ISO/IEC, the European Union's NESSIE project and the Japanese CRYPTREC project. The cipher has security levels and processing abilities comparable to the Advanced Encryption Standard.
In computer security, a side-channel attack is any attack based on extra information that can be gathered because of the fundamental way a computer protocol or algorithm is implemented, rather than flaws in the design of the protocol or algorithm itself or minor, but potentially devastating, mistakes or oversights in the implementation. Timing information, power consumption, electromagnetic leaks, and sound are examples of extra information which could be exploited to facilitate side-channel attacks.
The National Security Agency took over responsibility for all US government encryption systems when it was formed in 1952. The technical details of most NSA-approved systems are still classified, but much more about its early systems have become known and its most modern systems share at least some features with commercial products.
This glossary lists types of keys as the term is used in cryptography, as opposed to door locks. Terms that are primarily used by the U.S. National Security Agency are marked (NSA). For classification of keys according to their usage see cryptographic key types.
The vast majority of the National Security Agency's work on encryption is classified, but from time to time NSA participates in standards processes or otherwise publishes information about its cryptographic algorithms. The NSA has categorized encryption items into four product types, and algorithms into two suites. The following is a brief and incomplete summary of public knowledge about NSA algorithms and protocols.
The security of cryptographic systems depends on some secret data that is known to authorized persons but unknown and unpredictable to others. To achieve this unpredictability, some randomization is typically employed. Modern cryptographic protocols often require frequent generation of random quantities. Cryptographic attacks that subvert or exploit weaknesses in this process are known as random number generator attacks.
NSA Suite B Cryptography was a set of cryptographic algorithms promulgated by the National Security Agency as part of its Cryptographic Modernization Program. It was to serve as an interoperable cryptographic base for both unclassified information and most classified information.
The Microsoft Windows platform specific Cryptographic Application Programming Interface is an application programming interface included with Microsoft Windows operating systems that provides services to enable developers to secure Windows-based applications using cryptography. It is a set of dynamically linked libraries that provides an abstraction layer which isolates programmers from the code used to encrypt the data. The Crypto API was first introduced in Windows NT 4.0 and enhanced in subsequent versions.
A High Assurance Internet Protocol Encryptor (HAIPE) is a Type 1 encryption device that complies with the National Security Agency's HAIPE IS. The cryptography used is Suite A and Suite B, also specified by the NSA as part of the Cryptographic Modernization Program. HAIPE IS is based on IPsec with additional restrictions and enhancements. One of these enhancements includes the ability to encrypt multicast data using a "preplaced key". This requires loading the same key on all HAIPE devices that will participate in the multicast session in advance of data transmission. A HAIPE is typically a secure gateway that allows two enclaves to exchange data over an untrusted or lower-classification network.
A fill device or key loader is a module used to load cryptographic keys into electronic encryption machines. Fill devices are usually hand held and electronic ones are battery operated.
Cryptography, or cryptology, is the practice and study of techniques for secure communication in the presence of adversarial behavior. More generally, cryptography is about constructing and analyzing protocols that prevent third parties or the public from reading private messages. Modern cryptography exists at the intersection of the disciplines of mathematics, computer science, information security, electrical engineering, digital signal processing, physics, and others. Core concepts related to information security are also central to cryptography. Practical applications of cryptography include electronic commerce, chip-based payment cards, digital currencies, computer passwords, and military communications.
The Commercial National Security Algorithm Suite (CNSA) is a set of cryptographic algorithms promulgated by the National Security Agency as a replacement for NSA Suite B Cryptography algorithms. It serves as the cryptographic base to protect US National Security Systems information up to the top secret level, while the NSA plans for a transition to quantum-resistant cryptography.
