KW - 46

In the late 1980's, the KW-46 simplex cryptosystem was introduced in order to provide communications security (COMSEC) for naval broadcasts to naval fleets (Fleet Broadcast). It replaced the old TSEC/KW-37 and TSEC/KG-14 cryptosystems. Formally, this equipment is called "Fleet Broadcast Security Equipment, TSEC/KW-46". The KW-46 consists of the KWT-46 transmitter and the KWR-46 receiver (code name Vallor). The Royal Canadian Navy was a "customer" of this system.

The KWR-46 is a "low level" device that performs on-line decryption of digital messages, records, and data traffic received over the broadcast system at data rates from 50 to 9,600 bits per second in asynchronous, stepped or synchronous modes. It uses a continuous synchronization pattern situated directly in the transmitted traffic and will process up to and including TOP SECRET information. The KWR-46 is used for over-the-air transfer (OTAT) of crytographic material to support KG-84A/C use. Also supported is the North Atlantic Treaty Organization (NATO) Broadcast, the Navy Standard Teleprinter (NST), low frequency (LF) /high frequency (HF) R-2368 receiver equipment, and the High Speed Fleet Broadcast (HSFB). The KWR-46 is used on ships; the KWT-46 is located ashore.

Unkeyed KWR-46 equipment is classified CONFIDENTIAL. Keyed KWR-46 equipment assumes the classification level equal to that of the keying material but not less than confidential. Access to KWR-46 equipment is limited to personnel who possess a security clearance equal to the classification of the KWR-46 or its keying material, whichever is greater. Electronic key fill of the KWR-46 will only be accomplished through the utilization of the Key Tape Reader KOI-18/TSEC and AN/CYZ-10, DTD.

KWT-46(?) photo courtesy of U.S.N.