SECURE TELEPHONE UNIT (STU)

TM 11-5820-890-10-8

SECURE TELEPHONE UNIT (STU)

3.4.

STU Capabilities

3.4a.

To enable secure (up to and including SECRET level of classification)

PURPOSE

voice and data transmissions to be performed over commercial and

military telephone circuits.

The ANCD may be connected to the STU to serve as the source of data

ANCILLARY DEVICES

and information to be transferred via telephone.

COMSEC key, FH data (hopset/lockout, TSK, net ID), and SOI

APPLICATIONS

information may be sent over commercial and military telephone

circuits, distance unlimited.

At the receiving end of the STU transfer operation, data is received by

DATA RECEIPT

and stored in a target ANCD, available for use when required.

STU equipment is provided primarily for peacetime, non-battlefield

AVAILABILITY

use, but it can be used whenever commercial or military telephone

It is anticipated that STU transfer of

circuits are available.

SINCGARS-related key and data will be especially useful during

mobilization as well as peacetime management of widely dispersed

Reserve Component forces.

STU Characteristics

3.4b.

Secure telephone units require use of proper COMSEC key.

COMSEC

Synchronous data modes are at 2400, 4800, and 9600 BPS

DATA RATES

Interoperable Cryptographic Ignition Key (CIK) allows the use of seven

CIK

terminals.

STU is compatible with US commercial, DDN, and international

COMPATIBILITY

telephone systems.

STU meets requirements of NACSIM 5100A and is in compliance with

TEMPEST

MIL-STD-461B(RS03).

The STU IS a commercial off -the-shelf item and is not designed for

COMMERCIAL

outdoor, all-weather use.

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