Traffic Encryption Key (TEK)

TM 11-5820-890-10-8

4.1 b.

Traffic Encryption Key (TEK)

KEY

A traffic encryption key (TEK) enables the SINCGARS radio to operate

in a secure, cipher text (CT) mode of communications. The TEK is

loaded into the SINCGARS RT from an ANCD, or other COMSEC fill

device, if desired.

CHANNELS

A TEK may be loaded into all six channels of the RT, or channel 6 may be

reserved for OTAR use, covered below. Normally, the same TEK is

loaded into all five or six channels, but any TEK may be loaded into any

channel. If, for example, it is necessary to communicate with elements

of a different division, you would load their TEK into the channel you

intend to use for that purpose.

COMPATIBILITY

In order to communicate in secure, CT mode, both the transmitting and

receiving radios must be using the same TEK. When using more than

one TEK in your radio, it is important to record which channel each TEK

is stored in.

SCROLLING

The SINCGARS radio offers the operator the ability to move TEKs from

channel to channel. The process is called "scrolling," and it is easy to

per-form. (For detailed procedures, see Figure 4-1, below.)

Set CHAN switch to 1-5 (cannot scroll in chan 6),

(1)

where different TEK is needed

Press [CMSC] button; display shows TEK 1, TEK 2,

(2)

etc.

Press [CHG] button until TEK desired appears in

(3)

display.

Different TEK is now ready for use in channel

(4)

selected.

To return to original TEK, repeat steps (2) and (3),

(5)

or move the CHAN switch out of and back into the

operational channel.

Figure 4-1. HOW TO SCROLL TEK

4.1 c.

Cipher Text Operations

The purpose of using secure, CT communications is to prevent the

PURPOSE

enemy from intercepting friendly traffic.

Army policy calls for the use of CT mode whenever the capability is

POLICY

available.

EASE OF USE

With the built-in COMSEC feature of SINCGARS ICOM radios, ease

with which all RT channels can be loaded with TEKs and the practice of

using a common TEK throughout a division area makes secure

communication quite easy to perform.

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