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.
A key in cryptography is a piece of information, usually a string of numbers or letters that are stored in a file, which, when processed through a cryptographic algorithm, can encode or decode cryptographic data. Based on the used method, the key can be different sizes and varieties, but in all cases, the strength of the encryption relies on the security of the key being maintained. A key's security strength is dependent on its algorithm, the size of the key, the generation of the key, and the process of key exchange.
A secure cryptoprocessor is a dedicated computer-on-a-chip or microprocessor for carrying out cryptographic operations, embedded in a packaging with multiple physical security measures, which give it a degree of tamper resistance. Unlike cryptographic processors that output decrypted data onto a bus in a secure environment, a secure cryptoprocessor does not output decrypted data or decrypted program instructions in an environment where security cannot always be maintained.
Articles related to cryptography include:
The Clipper chip was a chipset that was developed and promoted by the United States National Security Agency (NSA) as an encryption device that secured "voice and data messages" with a built-in backdoor that was intended to "allow Federal, State, and local law enforcement officials the ability to decode intercepted voice and data transmissions." It was intended to be adopted by telecommunications companies for voice transmission. Introduced in 1993, it was entirely defunct by 1996.
Key management refers to management of cryptographic keys in a cryptosystem. This includes dealing with the generation, exchange, storage, use, crypto-shredding (destruction) and replacement of keys. It includes cryptographic protocol design, key servers, user procedures, and other relevant protocols.
There are a number of standards related to cryptography. Standard algorithms and protocols provide a focus for study; standards for popular applications attract a large amount of cryptanalysis.
STU-III is a family of secure telephones introduced in 1987 by the NSA for use by the United States government, its contractors, and its allies. STU-III desk units look much like typical office telephones, plug into a standard telephone wall jack and can make calls to any ordinary phone user. When a call is placed to another STU-III unit that is properly set up, one caller can ask the other to initiate secure transmission. They then press a button on their telephones and, after a 15-second delay, their call is encrypted to prevent eavesdropping. There are portable and militarized versions and most STU-IIIs contained an internal modem and RS-232 port for data and fax transmission. Vendors were AT&T, RCA and Motorola.
Fortezza is an information security system that uses the Fortezza Crypto Card, a PC Card-based security token. It was developed for the U.S. government's Clipper chip project and has been used by the U.S. Government in various applications.
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.
The Electronic Key Management System (EKMS) is a United States National Security Agency led program responsible for Communications Security (COMSEC) key management, accounting, and distribution. Specifically, EKMS generates and distributes electronic key material for all NSA encryption systems whose keys are loaded using standard fill devices, and directs the distribution of NSA produced key material. Additionally, EKMS performs account registration, privilege management, ordering, distribution, and accounting to direct the management and distribution of physical COMSEC material for the services. The common EKMS components and standards facilitate interoperability and commonality among the armed services and civilian agencies.
The KSD-64[A] Crypto Ignition Key (CIK) is an NSA-developed EEPROM chip packed in a plastic case that looks like a toy key. The model number is due to its storage capacity — 64 kibibits, enough to store multiple encryption keys. Most frequently it was used in key-splitting applications: either the encryption device or the KSD-64 alone is worthless, but together they can be used to make encrypted connections. It was also used alone as a fill device for transfer of key material, as for the initial seed key loading of an STU-III secure phone.
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.
A secure telephone is a telephone that provides voice security in the form of end-to-end encryption for the telephone call, and in some cases also the mutual authentication of the call parties, protecting them against a man-in-the-middle attack. Concerns about massive growth of telephone tapping incidents led to growing demand for secure telephones.
Over-the-air rekeying (OTAR) refers to transmitting or updating encryption keys (rekeying) in secure information systems by conveying the keys via encrypted electronic communication channels. It is also referred to as over-the-air transfer (OTAT), or over-the-air distribution (OTAD), depending on the specific type, use, and transmission means of the key being changed. Although the acronym refers specifically to radio transmission, the technology is also employed via wire, cable, or optical fiber.
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.
The AN/PYQ-10 Simple Key Loader (SKL) is a ruggedized, portable, hand-held fill device, for securely receiving, storing, and transferring data between compatible cryptographic and communications equipment. The SKL was designed and built by Ralph Osterhout and then sold to Sierra Nevada Corporation, with software developed by Science Applications International Corporation (SAIC) under the auspices of the United States Army. It is intended to supplement and eventually replace the AN/CYZ-10 Data Transfer Device (DTD). The PYQ-10 provides all the functions currently resident in the CYZ-10 and incorporates new features that provide streamlined management of COMSEC key, Electronic Protection (EP) data, and Signal Operating Instructions (SOI). Cryptographic functions are performed by an embedded KOV-21 card developed by the National Security Agency (NSA). The AN/PYQ-10 supports both the DS-101 and DS-102 interfaces, as well as the KSD-64 Crypto Ignition Key. The SKL is backward-compatible with existing End Cryptographic Units (ECU) and forward-compatible with future security equipment and systems, including NSA's Key Management Infrastructure.
A cryptoperiod is the time span during which a specific cryptographic key is authorized for use. Common government guidelines range from 1 to 3 years for asymmetric cryptography, and 1 day to 7 days for symmetric cipher traffic keys.
Attempts, unofficially dubbed the "Crypto Wars", have been made by the United States (US) and allied governments to limit the public's and foreign nations' access to cryptography strong enough to thwart decryption by national intelligence agencies, especially the National Security Agency (NSA).
