AUTHENTICATION A security measure designed
to protect a communications or command system
against fraudulent transmissions or simulation.
A U T O M A T I C D I G I T A L N E T W O R K
( A U T O D I N ) A worldwide automatic
communications system that provides automatic
BEADWINDOW A term describing a real-time
procedure used to alert circuit operators that an
unauthorized disclosure has occurred.
CARRIER the unmodulated signal originally
produced in the oscillator section of a transmitter.
CONFIDENTIAL Information the unauthorized
disclosure of which could reasonably be expected
to cause damage to the national security.
CRYPTOSYSTEM Information encompassing all
the associated items of cryptomaterial that are used
together to provide a single means of encryption or
DEFENSE SWITCHED NETWORK (DSN) A
nonsecure telecommunications telephone
interconnected network among military and other
government installations (formerly AUTOVON).
DIRECTED NET A net in which member stations
must obtain permission from the net control station
(NECOS) prior to communicating with other
stations on the net.
EMISSION CONTROL (EMCON) General or
specific restrictions placed on electromagnetic
radiations for a particular area or areas.
FREE NET A communications net of which member
stations need not obtain permission of the net
control station (NECOS) to transmit.
GATEGUARD A security subsystem that allows
commands to interface directly with the AUTODIN
system as part of the NSTA program.
LOCAL HOLDER A command or activity whose
COMSEC material needs are met by drawing the
material from a single CMS account.
MANUAL RELAY CENTER MODERNIZATION
PROGRAM (MARCEMP) An automation
support system for all aspects of HF message relay
operation in the Fleet Center.
PROSIGNS Letters, or combinations of letters, that
convey frequently sent orders or instructions in a
simple, standard format.
PROWORDS The phonetic equivalent of prosigns.
SECRET Information the unauthorized disclosure of
which could reasonably be expected to cause
serious damage to the national security.
S E C U R E T E L E P H O N E U N I T T H I RD
GENERATION (STU-III) Desktop phone unit
that provides users with both clear and secure voice
and data transmissions.
SEED KEY Special keying material used for the
initial electronic set-up of the STU-III terminal.
SERVICE MESSAGE A short, concise message
between communication personnel requiring