KL-43 AUTOMANUAL EQUIPMENT |
PROCEDURES
The KL-43 without printer, or with an approved printer, is approved for use for classifications up to and including TOP SECRET. Approved printers compatible with the KL-43 are included in the Preferred Products List (PPL). Other compatible printers and restrictions on their use are included in a separate list available from the Commanding Officer, Naval Electronic Systems Security Engineering Center or Commander, Naval Investigative Service Command.
Since KL-43 printers do not automatically mark printed messages with the classification level, a statement of classification shall be included in printed messages processed by the KL-43.
If knowledge of the time a message is sent is critical to proper interpretation of the message, that message shall include a date/time/message count feature in the plain text.
KL-43 encrypted messages may be transmitted via any medium (Morse Code, verbal, modem, etc.).
KEYING
KL-43 traffic encryption keys (TEK) are operational keys (KAK) or exercise keys (KXK) having either a 24-hour cryptoperiod or weekly cryptoperiod when using the daily key update feature. Each31 segment TEK canister is superseded monthly when using the 24-hour cryptoperiod or superseded every 6 months when using the daily key update feature with the weekly cryptoperiod. A used TEKtape segment may be retained up to 72 hours after its supersession to accommodate delayed messages; however, the key must be protected to preclude traffic compromise through loss or espionage until its destruction. KL-43 training keys (KTK) and maintenance keys (KMK) have no cryptoperiod and each key segment may be reused until unusable. Training keys and maintenance keys will not be used for over-the-air transmissions. All KL-43 and KL-42 key tapes are compatible even though the equipment is not.
Cryptonets should be kept as small as the operation permits to reduce the possibility of compromise, but some KL-43 nets are by necessity large. KL-43 cryptonets employing a 24-hour cryptoperiodshall be kept to 200 users for TOP SECRET and 1000 users for SECRET and lower. If the daily key update feature is used, the cryptoperiod is weekly (7 days), and cryptonets shall be kept to 30 users for TOP SECRET and 150 users for SECRET and lower. Controlling authorities requiring larger nets and/or longer cryptoperiods must request approval from the CMC (CCT).