• 

CSGAS-70 

StJBCOM!.l[ft.BI Rlll'Utr !10. 22 

Jl1IOWQDI :rem Bl .ABM! SBCURr.l't .AGmlCY '1'.ICBIICAL ~ 

Sub39ct: Initiation of D/A Pro3ect Bo. 29-66-030, HC-4 Marlr n am 

Alphabetic Subst1tut1om Jlrv1C$ 

l. RM'WCIB: 

a. IE frcm Chief, Ma.cbiae Branch to Chief', Reaearcb and Davelo'P1119nt 

D1?1&1CD, elated 6 3amary 1949, Subject: IC.Ja. Mark II. 

b. DS trom Chi.et, Macbiae :Branch to Chief, &search and DeTelopmsnt _ l>1Y1sion, dated 17 Jamar7 1949, Sub3ect: Military Cbaraoteristica of the !'C...4 

Mark II and Alphabetical Substitution Dence. 

2 o MSCUBSIOlf: 

a. Mancias Concerned: 

(l) Casmzant A/!}me1: Wav1 

(2) Directins .Agency: B&."7 

(3) BequeatiDg .Asenc7: Arrq Securit1 Agenc1 an4 EaT7 

(4) Part1c1pet1ns Ageno7: Army Securit7 Agenc7 

(') Coord:tnatins Asenc;r: llaT7 

(6) other Probable Interested Agenciea: USAF 

b. hrpoae: 

The purpose ot PrcJect Bo. 29 .. 66 .. 030 is to deTelop an improved 

'basic •chine and an au:dll.ar7 device for perf'o:rming numeric encl alphabetic 

eubstitut10IDS and otber operatiG!lll in cr;n>tClOSJ'. Thia equipment ll'ill be 

operated b7 CSGAS-92. · ., 

c. ~or1pt1on: 

, 

Tbs BC-4 Mark ll will be analcsous to the conmerical IBM reproducer 

eJCCept that there 'ldll be an additional set ot 80 brushes in each feed and a 

coordinating feature which v1ll control feeding depenc11Dg upOll the reedi1>3 in 

tbe two te6lds. In ad41 tion 1 t vi ll be designed to permit attachment est various 

B}>ec1al dn1cee such as the alphabetic substitution device tor controlling 

i'ta QlHtl"&t.icme. The a1.pba.bet1c substitution device will permit the encipher~ 

m&nt or 4eo1phermeDt ot l to 5 element units at the rate of 100 units per 

minute. The substitution device Will bave a 32 x 32 matrix vbich vill be 

campl,tel7 ~1.Xible to accOllJIDodate any set or 32 32..elemsnt sequences. 

Jeclassified and approved for release 

JY NSA on 08-07-2013 pursuant to E.O. 

13526 
cl. Related Material: 

The 1'C-4 Nark I Machines now in use b7 CSOAiJ.92 werebuilt for 

tbe 1a.., dur1ns the Var and are 'be4111n need ot roplacement. 'tbeir 4eaigD 

does not permit 1181)7 essential t.unbt1ona which v111 be 1nccrpon.te4 in the IC-4 

Mart II. . . 

• -~DavelOJ!l!llt Bia~ Stat2: . . . . . . i . . 

A F0.1eot ilaa been .set U\) b7 the ~ dr Ships, t~ 4eeign am 

enatruct1on at the BC-4 Mark lI ·&Iii far certain awd.Uaey equil'JlleDt ae 1ncl1cate4 

:lD the epeo1t1cat1ona att.aobGi; u an Bxhibit. Deatgn vorll: baa been completed 

1>7 the lnternatitcaal lus1neaa ~inea CorparatS.oa and conatrt1ct1on is UD\erv&J. 

! . ! . 

f. ~Po9e4 DeveioPnt: 

Th1a pro3en Will be: con4uctec1 \1D4er Oontract nesotiated by the 

lla'YJ, to vbioh tba Arm:j Sequl-1.tr Agenc7 rill tranaf'er f'm14s. 

(l) Phase• ot theproJeot 1nclu4e 4evelopmemt and fm81nMriJ>g and 

een1ee teats. 

(2) Four aer'rlce test models ot tbe '°-4 Mart II will be required 

and on.eaenice teat mod.el ot the alphabetic aubatitution 

ctence will be nqu1red. The sen1ce teats vill be ma4e b7 ~-92 am BaVJ. · 

(3) Pr1orit7 lC 1• recomamclec1, v1thin tbeterma ot Par 3a(2)(c)· 

' Ot War Departiant C:trcuJ.mo 71, 18 March 1947, 'Mcause of the 

intended. operat1anal use. · 

(4) The estimated coet flt this proJect to theArnt7 Securi t7 Ag,enc7 

is $74,800.; . - . 

(5) Dmtlopment vill be completed in approximateb' 18 months. 

8• Securitz: Claas1f1cat~on..t 

(1) The equ1pmmt vhile ~ cle•elopment Will be claes1fiecl 

CODIIDTIAL. · 

(2) . This ·equf:pment vil~ be cons1cleretl 1D the "11m1te4"' cateso.r10· 

(3) Cz7ptograpb1c clearance will not be reqUre4 'ccr peraomae). · concerned. in the developa8nt. 

3. RICCllMIBDlfimB: 

Tbe Subcommittee reomnan4a that Pro.1ect 29-66-030, llC-4 Mark II and 

Alt>Jlabetic Subet1tut1m Dence, be established, claaa:ltiecl ae ».Yelopment Tn>e, ~ e Test TJ'pe, aDl aesignecl a Pl:! or1 t7 ot 10. 

-GlJAJFJDENTJAt 
l ln~l1'"!l:b.1Mt "A .u 

CfiAVADENTfAL 

· USCAAD 

:i.tO .UC&GEN 

\:h.airman • Crypt.r:. i tl!gi c 

Subcommii:tee .!' ASA'l'C 
' 

EXHIBIT "A a . 

Proposed Military Cllaracteristica tor BC..4 

Mart II and Alp!Ja.betic Substitution Dence 

Io General Inf'Ol'llation 

A. Ob,iect1Ta 

.1. '!be ob39ct ot thia clevelop&Dt is to produce (a) a \Mlsic machine 

aimilar tn nature to the present RC-4 (a type ot p.reaeneins punch) but having 

increased capactt1 ot control aDl COJllPuttt.tion, more flexibility anc1 improved 

aocurac1 and (b) an alphabetic substitution device associated with the be.sic 

machine. 

2. Equipmnt ot the Q'pe cleacr1bed herein is required to ezpedite 

clecipherment and to permit substitution operations ot various tn>es. In 

a4dtt1on, other crJPtologic funct1one, e.a ... , those involvecl in transposition 

solution and decodins, oan be peri"ormed. 

ll. Functional Cbaraoteriatica 

1. The 110-4 Mark II shall ha-ve as its general f'mc~i~: 

a. Transcr1pt1m of 1Dfet"ID&t1m f~$. ®e f'11.8 or punched cards to 

ant.tber • 

. 

b. Comparison at data betWeen two files ot cards 1n such fashion 

as to control bOth the teediDS and P~hins ot cards. 

c. 88Dsing ot iaf'm'IDation tar further analysis am punching the 

result or· that aml.ysis into the same card from which the 

sQUree ·aata n.s read. 

a. Contr•l by basic machine of various auxiliaey devices. 

2. The alphabetic substitution device should be ~.t.tac~ble to the 

basic machine ana shall permit aimltaneous decipherment or encipherment of 

1 to 5 poait1an11 through a plugsable matrix having a caJl8City or 32 32 ... ele:ment 

alphabets. 

C. 'l'entatiYe Technical Considerations 

l. 'l'he basic machine shall have a form SDalo.goua to the present IBM 

type 519 reprod.ucer vitb. the tollowil)g pr1ncipal,d1tterencea: 

a. Three- reading stations in the reproiluce teed. 

b. Two rea41ng stations in the ;;t:~:dJ. f'tHid1cne preceding and one 

following the pancb station. 

CDNFID£14TIAl 
c. Coora.:tnatil28 feature vh1oh would permit a control ot 

feecl1DS in both feeds tram reaclSJ)s ar the cards. In 

adcli t1m, the coa1'dinating f~ture &ball }>9l'll1 t control 

Of punching a.Di ether funetiona of tbs machimo 

a.. Prorision f'cr at-tachm'9nt and. ccimtl'ol at aux1118l"1 dericea .. 

2. 'rhe alphabetic s11ToaUtut1cm tJerice smll baTe the toU.owmg 

charaoteristics: 

a. A pl1J8Pbll.e matr:iz permitting tbe plugsiDg Of 32 32-&lem&nt 

alphabets .. 

b. A choice ot e:q 32 out ~ the 38 atanaard IBM cc41!1SS tor 

r&Slllt punchiDB. 

c. A choice Gt flZl7 32 ou.t ct tbs 38 ataD!arcl IBM cocUnga to 

control the cocarcUnates at tbs, m:trix. · 

do .Abilit;v to bypass tha matrix whenever a P-pecial. character 

representing a garble occurs in either er both key and 

cipher (er plain). 

&o Autoare.tic checking f'eaturell i» iDaunt SCClll"&C;J of 1'9BUlta. 

t. Capacit7 to cpenite tram 1 to 5 positions tor each card at 

the rate ot 100 earc18 a mimte. 

D. Tb.1a equipmnt mall be used' at timed eta.t1cna. 

B. '!he equ1)1Jent eball ble installed :ln f'1xecl IBM 1nstallat1cma of the 

Arrq Socuri t7 .Aeenc7 ana ether cr;n>tolasic agencies .. 

P. The ve!ght dl the equipment aball not exceed 125 l'bll l)er square toot 

at bnrins area. The )1.laxi'lllWD d1msm1om shall ~ot emceed might 6 f't., vidth 

4 ft., lensth 5·ft. 

G. The desirable lite expectanoe at the equipment witb reasonable maintenance 

s!lall be 5 Je8r8 lDDder either peace er var aonditiha 

II. Pertarmance Requirements 

A. Bqu1}8!lt shall conf'orm to tbe l88Jll9 stanaarda requ11"ed. far c0111118l'C1all7 

produced. IBM •chines. 

III. ()perationa azx1 Maintenance Consideration 

Ao Equipnant shall be capable at c~nt1nuoas operat1oo for 20 houra a ds.7 o • 

- CBNRBEN TIAt-
B. !l.'b• baa1c • machine and aux11:1.ar7 4orico aball require no more tban 

one operatO.r aaa. eball be mintaine4 an4 ftl"f'1cei b7 the same personnel who 

maintain ancl aenioe ot.!Jer DM equipment. 

c. ~or1e1on ffll: 11el4 ~. 

l. Requirements t°' t:leld binte-;1a.D0e a!lall be simi"lar to those for 

otber DM equlpnmt. · 

IV. Pb111cal CJl&raoter1et1ca. 

A. Bcpaipnent &eatso aball take into cona1deze:ticn s111pl1c1 tJ of ma1ntemnce,, lllm1nmm possible ue Cf s+Amdanl pane aac1 other aimU.ar ocma1cleratiOD& 

normlq 1Dvol'h4 1Dthe dea2gD t1l DM equ.1.pment. 

B. The eq\lipmmt Aa.11 opm1te tram 110 volte 60 c,ele a1r4le pllaee 

power euppl.J. . . 

C. 'l'hia eQU1pmnt aJaU 'be ct .. a:lped for use 1D PhUe IV ot air operatiomi. 

D. The cODa~ction :j..mo f.- aa rugednese, temperature. ·limits, etc,. 

allall pmrd.t eb1i:aaent to aD6. mtallation at eiq fixed IBM 1Datallat1on at 

the ~·securitJ ltpflc7. 

OONFIDEMltAt.