rrsA CIRCULJ\R 

Ntn.fBER 101-l~ 

NAT10NAI., SECURITY AGENCY' 

Washini;-ton 25, D. c., 22 August 1955 

EFFECTIVE uwrIL RESCINDED OR SUPERSEDED 

PROCEDURl'~G FOR SERVICING COMINT'AND ASSOCIATED 

'l'HAFFIC FORWARDED VIA ELECTRICAL MEANS 

PURPOSE • • • • • • • • • • • • • • • 

SCOPE • • • • • • • • • • • • • • • • 

GENERAL INSI'RUCTIONS • ••••••• 

SERVICE REQUESTS • • • • • • • • • • 

REPLIES TO SERVICE REQUESTS • • • • • 

VOLUNTARY CORRECTIONS • • • • • • • • 

SECTION I - PURPOSE 

SECTION 

I 

II 

III 

IV 

v 

VI 

It is the purpose of this circular to augment instructions 

contained in appropriate ACP series and supplements thereto. 

SECTION II - SCOPE 

1. This circular prescribes standard procedures to be used 

in the preparation and transmission of service messages related 

to COMINT traffic. 

2. To be 1'u1ly effective electrically-forwarded COMINT 

traffic must be delivered letter perfect to the addressee(s) as 

quickly as possible. Therefore, when a cipher tape is wholly 

or partially undecipherable, an appropriate service message will 

be expeditiously sent before other messages of the same or 1ower 

precedence. Replies to service messages will be similarly he.nd1ed. 

3. This circular provides for the inclusion in service 

messages of specific data which will expedite the ha.ndling of such 

messages and the traffic to which they pertain. 

SECTION III - GENERAL INSTRUCTIONS 

1. Each recipient is requested to review this circular in 

detail. If any portion is not clear, please addre~s inquiries to 

the headquarters from which this document was received. Further, 

you are encouraged to :f'urnish comments and suggestions for changes 

to this circular through the same channels. 

2. For the purpose of this circular, service messages are 

divided into two categories: (1) unclassified or plain text and 

(2) classified or encrypted text (cryptoservice). 

SECRE'f 

Declassified and Approved for Release by NSA on 02-21-2014 pursuant to E.O. 13526, FOIA Case# 0 
SPJGRE'±' 

NSA CIRCUlJ\R NO. 101-4 22 August 1955 

a. Unclassified service messages will be restricted to 

requests for reruns {INT ZDK) of traffic received via off-line 

facilities and appropriate instructions preceding the retransmission of encrypted traffic. 

b. Cryptoservices will be prepared in accordance with 

the provisions of KA.G-1/'rSEC Cryptographic Operations. 

(1) Service messages, except requests for reruns, 

must be classified when they are transmitted via 

off-line facilities and refer to on-line transmissions. 

(2) When on-line facilities are available, they wil1 be 

preferred for service messages and replies thereto. 

3. There will be no ,.--·~ernal indication o:f the service nature 

of an encrypted service me··:1ge. The use o:f expressions such as 

GRSVC, speci~l serial numbers, routing indicator suffixes, and 

other similar phrases is nob allowed. 

4. The utmost cau~lon will be exercised to prevent a rerun or 

retransmission of a tape associated with a cryptographic compromise. 

SECTION IV - SERVICE REQUES'l'S 

1. Precedence - A service message wil1 normally be assigned a 

precedence equal to that of the cited message. 

a. A service message may be assigned a high.er precedence 

when, due to the time lost in servicing, faster communications 

handling is required. 

b. When more than one message is cited, the service message 

Will normally be assigned a precedence equal to the highest assigned 

in the messages cited. 

2. Message text - The text of a service message, though brief, 

must permit ready identification of the cited message and clearly 

indicate the action required. 

a. Reference to the date-time group, and section data, if 

applicable, is mandatory. 

b. If the date-time group is unreadable, reference to the 

time of filing (TOF), if available, is requested. 

c. If the cited message was received via off-line facilities, 

the appropriate station serial number will be included in the service 

message. 

- 2 -

SE€RET 
.. S~RJ-li"rii~M1ss9 \....Ilb I 

NSA CIHCULAR NO. 101-li 22 August 1955 

d. I:f t.hc cited message was received vla on-l lt1e facil .. 

!ties, the appropriate channel nuJ'Tl.ber and date will be pro~ided. 

e •. 'J'he abbrevlation "COSIR" (Cite Our Service In Reply) 

mo.y be included in the service message i r such use will f'acili to.te 

handling of the reply. 

3. Classi:fication - All service messages, except requeats for 

reruns and retransmissions, shall be classi:fied according to the 

contents of the text of the service message and never less than 

CONFIDENTJ AL. 

SECTION V - REPLIES TO SERVICE REQUESTS 

1. Replies to requests for cryptoservice or tra.nsmiooion 

service will be handled prior t~ processing current traffic or tho 

same or lesser precedence. 

2. Retransmissions or mul.tiple address meseaees will be sent 

on1y to the requesting station. Reencryptione and explanatory serv~ 

ice messages will be sent to all addressees included in the original 

transmission. 

3. When preparing for off-line transmission a reply to a serv~ 

ice request, procedure line "A" o:f internal message :format will be 

utilized. Use of the following phraseology is reconnnended as it 

provides an effective means of flagging replies to serviced traffic: 

(1) (2) (3) 

"CRYPI'O NO'l'E X SYS ---------- X HW ------------ MY ------------" 

(1) Identification of service request. (DTG or Cite number). 

(2) Indication o:f service r.endered. {nerun, reencryption, 

corrected copy, etc.) 

(3) Transmission IJl'G if message being serviced was originalfy 

transmitted via off-line facilities or channel number and 

date i~ on-line :facilities were used. 

SECTION VI - VOLUNTARY CORRECTIONS 

Due to varied logging procedures and,internal distribution 

requirements, it is essential that a voluntary transmission of a 

correction to a. message include in procedure line "A" of the internal 

message 1'ormat: 

- 3 -

SECRET 
~~ 

NSA CIRCULAR NO. 101-4 22 August 1955 

a. Reference to the date-time group or the original transmission and, if the message was transmitted via on-line facilities, 

reference to the channel number and date of the on-line transmission. 

b. Reference to the section number, if applicable. 

c. Identification of the traffic type, i.e., the tra:f'fic 

identification line. 

BY COMMAND OF LIEUTENANT GENERAL CANINE: 

OFFICIAL: 

DISTRIBUTION V plus 

Special 

JOHN B ACKERMAN 

Major General, US Air Force 

Chief o:f' Starr 

SECRE'f 

..