KSD-64
Encyclopedia
National Security Agency
The National Security Agency/Central Security Service 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...
-developed EEPROM
EEPROM
EEPROM stands for Electrically Erasable Programmable Read-Only Memory and is a type of non-volatile memory used in computers and other electronic devices to store small amounts of data that must be saved when power is removed, e.g., calibration...
chip packed in a plastic case that looks like a toy key
Key (lock)
A key is an instrument that is used to operate a lock. A typical key consists of two parts: the blade, which slides into the keyway of the lock and distinguishes between different keys, and the bow, which is left protruding so that torque can be applied by the user. The blade is usually intended to...
. The model number is due to its storage capacity — 64 kB (65,536 bits), enough to store multiple encryption keys
Key (cryptography)
In cryptography, a key is a piece of information that determines the functional output of a cryptographic algorithm or cipher. Without a key, the algorithm would produce no useful result. In encryption, a key specifies the particular transformation of plaintext into ciphertext, or vice versa...
. Most frequently it is 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. Less often, it is used alone as a fill device
Fill device
A fill device is an electronic module used to load cryptographic keys into electronic encryption machines. Fill devices are usually hand held and battery operated....
for transfer of key material, as for the initial seed key loading of an STU-III
STU-III
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...
secure phone.
Newer systems, such as the Secure Terminal Equipment
Secure Terminal Equipment
Secure Terminal Equipment is the U.S. Government's current , encrypted telephone communications system for wired or "landline" communications. STE is designed to use ISDN telephone lines which offer higher speeds of up to 128k bits per second and are all digital...
, use the Fortezza
Fortezza
Fortezza is an information security system based on a PC Card security token. Each individual who is authorized to see protected information is issued a Fortezza card that stores private keys and other data needed to gain access...
PC card as a security token
Security token
A security token may be a physical device that an authorized user of computer services is given to ease authentication...
instead of the KSD-64.