Position 34 through end-of-routing signal (start-
of-routing signal and addressees) —The positions
reserved for routing are made up of two sections: start-
of-routing signal and the addressees’ routing indicators.
The start-of-routing signal consists of two consecutive
hyphens and will always precede the first addressee
routing indicator. Addressee routing indicators are
listed immediately following the start-of-routing signal.
A message can have a maximum of 500 routing
indicators in these positions. If a message contains 501
or more routing indicators, the message will require two
separate transmission. In this case, all routing
indicators that have the same first four letters should be
in one transmission
End-of-Routing Signal —The end-of-routing
signal consists of a period (.) and is inserted in the
position immediately following the last addressee
routing indicator.
SECURITY WARNING (FORMAT LINE
4). —A security warning is the first component of
format line 4. The appropriate operating signal (ZNR or
ZNY) will always be followed by a classification
character repeated five times. The operating signal and
classification characters are as follows:
ZNR UUUUU —For off-line encrypted messages
and classified messages transmitted in the clear;
ZNY EEEEE —For unclassified EFTO messages;
and
ZNY, followed by CCCCC, SSSSS, or
TTTTT —For Confidential, Secret, or Top Secret
messages, respectively.
For SPECAT and SPECAT SIOP-ESI messages,
the five redundant security characters are followed by
an oblique (/) AAAAA for SIOP-ESI or BBBBB for
all other SPECAT messages. For example, format line 4
for a Top Secret SPECAT message would be:
ZNY TTTTT/AAAAA(2CR, 1LF)
END OF MESSAGE (EOM) (FORMAT LINES
15 AND 16). —Format line 15 is the EOM validation
line that is used to inhibit suspected straggler messages.
Format line 15 consists of the SSN in format line 2
preceded by the number sign (#). Format line 16
consists of the EOM functions. The EOM functions
consist of normal teleprinter ending procedure when
five-level Baudot code is used (2CR, 8LF, 4Ns,
12LTRS). However, for ASCII, 12 delete functions are
used (12DEL). The EOM for the message with format
line 2 shown in figure 1-2 would be as follows:
Format lines 1, 2, 4, and 5 must all be accurately
prepared. Backspacing, lettering out, double-spacing,
or using two or more FIGURES and LETTERS
functions in sequence will cause the ASC to reject the
message during attempted transmission from the
originating station. The EOM validation appearing in
format line 15 and the EOM function in format line 16
must be prepared in uninterrupted sequence, be letter-
perfect, and be without corrections.
General Teleprinter Rules
A leader must precede the header to ensure
acceptance and transmission of the first character of the
message header. The leader for the five-level Baudot
code (most common) consists of at least six blanks and
six letter functions. The leader for the ASCII (eight-
level Baudot code) consists of at least six nulls and six
delete functions. This will ensure acceptance and
transmission of the first character of the message
header.
When a message is assigned dual precedence, the
higher precedence is shown in format line 2 (position 1).
Both precedences are shown in format line 5.
Communications personnel of tributary stations
must ensure that a record is made of the time of file
(TOF) and the time available for delivery (TAD). These
times are used to determine message-processing times.
Message Lengths
Messages cannot exceed more than 20 lines of
heading and text, beginning with format line 5.
Messages that exceed the 20-line limit must be divided
into pages for transmission. The second and succeeding
pages of a message are identified by the page number,
the routing indicator of the station of origin, and the
SSN. The security classification of classified messages
follows the page identification. After the first letter of
the classification, you must separate each letter by one
space from the previous letter. For example:
On unclassified messages, "UNCLAS" is placed after
the page identification with no spaces separating the
letters.
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