NSA encryption systems

The <a href="/facts/National_Security_Agency/Sg6MGV1o">National Security Agency</a> took over responsibility for all <a href="/facts/US_government/VJCxUaf7">US government</a> <a href="/facts/Encryption/16q29Fdv">encryption</a> systems when it was formed in 1952. The technical details of most NSA-approved systems are still <a href="/facts/Classified_information_in_the_United_States/YNyn6wGA">classified</a>, but much more about its early systems have become known and its most modern systems share at least some features with commercial products.
NSA and its predecessors have produced a number of <a href="/facts/Cipher_device/GpzzQE7g">cipher devices</a>. <a href="/facts/Rotor_machine/xWJgVfIb">Rotor machines</a> from the 1940s and 1950s were mechanical marvels. The first generation electronic systems were quirky devices with cantankerous <a href="/facts/Punched_card/44WsPulQ">punched card</a> readers for loading <a href="/facts/Key_(cryptography)/5W5PAmT4">keys</a> and failure-prone, tricky-to-maintain <a href="/facts/Vacuum_tube/VHd1BNLq">vacuum tube</a> circuitry. Late 20th century systems are just <a href="/facts/Black_box_(systems)/hJeAGnIz">black boxes</a>, often literally. In fact they are called <a href="/facts/Blacker_(security)/Nm48IQ0a">blackers</a> in NSA parlance because they convert <a href="/facts/Plaintext/tWnBDCgE">plaintext</a> classified signals (red) into encrypted unclassified <a href="/facts/Ciphertext/luNTs4sY">ciphertext</a> signals (black). They typically have <a href="/facts/Electrical_connector/rJh0cHs6">electrical connectors</a> for the red signals, the black signals, electrical power, and a port for loading keys. Controls can be limited to selecting between <a href="/facts/Fill_device/xJf07vBv">key fill</a>, normal operation, and diagnostic modes and an all important <a href="/facts/Zeroisation/DCxhb9jT">zeroize</a> button that erases <a href="/facts/Classified_information/og7wn3tD">classified information</a> including keys and perhaps the encryption algorithms. 21st century systems often contain all the sensitive cryptographic functions on a single, tamper-resistant integrated circuit that supports multiple algorithms and allows over-the-air or network re-keying, so that a single hand-held field radio, such as the <a href="/facts/AN%2fPRC-148/NFlSv9xt">AN/PRC-148</a> or <a href="/facts/AN%2fPRC-152/6w9QfeI1">AN/PRC-152</a>, can interoperate with most current NSA <a href="/facts/Cryptosystem/GyDVJ4D0">cryptosystems</a>.
Little is publicly known about the algorithms NSA has developed for protecting <a href="/facts/Classified_information_in_the_United_States/YNyn6wGA">classified information</a>, called <a href="/facts/Type_1_encryption/uKCkqR8E">Type 1</a> algorithms by the agency. In 2003, for the first time in its history, NSA-approved two published algorithms, <a href="/facts/Skipjack_(cipher)/pxHYFxTj">Skipjack</a> and <a href="/facts/Advanced_Encryption_Standard/HdXGBY2Q">AES</a>, for <a href="/facts/Type_1_encryption/uKCkqR8E">Type 1</a> use in NSA-approved systems.

NSA encryption systems open-in-new

NSA encryption systems