.: 

W.P. & T. Div. 

MDORANDUAi T01 

REF ID:A522101 

WAR DEPARTMENT 

OFFICE OF THE CHIEF Sl~L OFFICER 

WASHINGTON 

March l, l9)J 

Rbsearch & Develo,tl&ent Division. 

In accordance with the_ sugge3tion made in a conference 

with Lieut. 11.der, there is attached hereto a draft of •ti1litnry 

Char111.Cterletice of a cipher machine for use ln measage centers 

or division and higher headquarters. tour co1Q111ents are requested. 

.lttachedi 

Dr Bift ( dupl.) 

s. B. Akin, 

Major, Signal Cori)th 

JA'pproved for Release by NSA on 11-19-2013 pursuant to E.O. 1352§ 
.: , 

tr • .... REF 

11.U PLANS AND TWNINO DIVISION 

DATE • 1 )..- ') 13 ~ • 

TOI ____ ....... ____________________ ___ 

Ex. c. 

Fiscal Sac. 

Met•l Div. 

Pers• Div. 

rhoto. Div. 

Pe&T.Div. 

I\.. & !h Iiv. 

Sup. Div. 

W.D. Mag. Can. 

Maj• Akin 

Capt. Moran 

Capt. ~al dwi n 

vcapt. Borden. 

Re eol!llllendat ion 

Lt. Rhoads 

Lt. Corderman 

Mr. J'riedman 

Mr• kowlett 

Mr. Sinkov 

Mr. l(ullbach 

Mr. Hurt 

Miss Cloyes 

Miss Newkirk 

Miss Pear~ on 

)l.ise Janssen 

Mr• Cla.ric 

Concurrence or rec M'.lllen dat ion 

(Your Div. 

Notation l File in(Gen. Biles 

('(l.P. cl T.Div. 

Notation and return 

Notation a.r,d mail 

Notation and 

tra.nl!llli ssion to Ex. 0. 

Preparation of dra.tt ,,r reply 

for signat1.tre by ------- Signal Corps !ulletin 

Your aeti,,n 

Your informaticn 

Approval• 

FRCJI.• Jt.aj or Akin 

Captai 11 )f.oran 

Capt.ain BaldwiY'n 

Captain Borden 

)f.r. fried1rar1 

MARKS I 

~ kt_. &i If . f :/13 
; -- . REF ID:A5221M 

MILITARY CHARACTWS'l'lOS OF CI.PllEH MAOHUI. FOR USE IJI llEBSAGE 

cmms 01 DIVISIOI AID HIGHElt ltUDQUAR'tlRS 

.!• This •achine should be dedgned tor the !'undaaental purpose 

of encipher~ and deciphering 11eseages with speed, accurac,-, and 

great f!ecur1t,y • 

.&• It should consist of two units, (l) a oryptoeraphic unit pro-

- vided with a. :26-eleDlent lcqbo'ard, and (2) a printer unit IUi.table for 

aak1ng a per£1eaent record, j,lre!erabl7 a page printer. The orn>tographio 

unit is the part 1n which the enciphering or d•ciph.ring operations· tU.e 

place; the ~rlnter unit is a.ss'3ciated with the crypto~rapbic unit and 

11ere.i., prints tbe cipher text, 1n cue ot encipheraent, or the plain 

te.;.(t• 1n case of deoipl'umu.ent. The cryptogr~ph1o unit should be so 

conetructeci that 1n case of printer ta1lure cryptographic operation 

ae,y be continued by means o! electric 116ht-bulb 1.Ddicatora on a laap 

J.• The weight of the cryptographic WU.t including ita OUTJinc 

unit 

cue, ehould not exo•ed 25 pounds; that or the printv', includilli its 

oerryJ.na oa.e, 3.5 pouads. Bot.h wait• mould be fairq rugged in construction, capable of wi thatanding th~· J arrini incident to vehicular 

tranapo.rtation when a Headquarters llOYea to a new location. 

!1• 'the ap,paratus should be deaigneci to operate on 8-vol t storage 

batt.e17 auppl.J at. teaa>or817 and •Mi-teapora.ey headquarters; 611 60 07alee, 

110 volts, 1.c. power 1UppJ.¥ at peramietnt headquarter• end offices. 
REF ID:A52210l• 

!.• The oey?to~--rs.pb1o operations ehoulu be controlled by" an external oloment which is variable end ia not an 1ntrinsio _po.rt of the 

meahanism itself, suoh ·as a perforRt.en tape si.ailar to that employed 

in printing telegre.ph apparatuB. The underl7ing ary;itographic principle should be thnt of Ill continuous, nonrepeatinr, un1ntell1g1ble or 

rando11-aixed key sequence of characters governing the encipherment of 

auocessiv& l&ttera. 

l• The aini.llua speed of op&ration in enciphering and printing a 

messaa;e should be approximately 60 character! 9er m1nuto; the optim.wa 

speed would be that to be expected of a coapetont typist, approximately 

200 - 250 charaot6rs per 13inute. 

E.• In its ulti•ate form the whole apparatus should be capable of 

b6i%: uaociate<i directly with a trMsmitter !or l'lire or radio communication, &o that operation of a looal cryptographic keyboard will cause 

si~nals to be trannittf:d whioh will actuate a dietant printer u;:,on 

which the cipher mesaAi• mq be t7ped in ite cryptograpbed' tors, or, 

if pr&Qticable, direct~ into its plain-text fora, paeein( automatically 

throuib the 1ntenned1a.te stace of decr)"ptographing on th• c17,?tographic 

unit. 

•