-----~--~~~~--.....,.----------------~~----1911!1!~-- ) ....., - ........ ..... 

The Director 

National Security Agency 

Arlington Hall, Vriginie 

Sir: 

REF ID:A66773 ~ 

Da"d Kahn 

Wandlll>I' Gate 

(-.real !'teck, New York 

December 2a, 195~ 

The recent criticism of the nationalsecurity system 

by the Am.erit"'~n Association for the Advancement of Science ~rompted the New York Cipher Society to issue the enclosed 

To... Improve Our Cryptographic Defenses." As you can see, the 

statement first corrects an unwitting error in the Association's 

statement and then furthffr explains the danger inherent in the 

present overly-restri~tive cryptographic security system. We 

confine ourselves to our particular sphere of competence. 

We are sending y~u a copy or this statement in the 

hope that the logic ot i~s position will con~ince you to 11berali ze our current cryptographic eecurity program. 

• "To Imppove OUr Cryptographic Defenses" was adopted without objec~ion by the New York Cipher Society at our regu- lar monthly u~eting held in New York on December 20, 1954. In 

addition to the Board of Directors of the American Association 

tor the Advancement of eoience, copies are being sent to President Eisenhower and to ot.her parties. 

We hope t~at this statement will prove 0£ some assistance to you ~n your worK of guarding the communication lines 

which are so vita.L to the- nation. If' you have any questions concerning tha statem<:.nc;, ple-l:ae do not hesitate to wn te 11a41 

Very truly yours, 

~J_,. " . ¥ ... r1 ....... •/ 

P11f:l&ident 

New YorK Cipher Society 

@'pQJoved for Release by NSA on 05-01-2014 pursuantto E.O. 1352a ' - ·~ 
REF ID:A66773 e 

fH IW folk Clpbe• SMf.n7 a...-a with the priatd.plea 

ulliaa I•• P"l•••r flttid.oa ot ed••lft• btenaUoa tlblob wen 

.. , tOl'tJl in ~.i•rm.-.sag '1le 8•11• ot la,lonal S.Wli*,. 1t1 

th• Board ot DineMr• d 'b• Aael'lou AaeoAatia ta ti&• AA&.,..,.. 

••• et SaiMe•• Ja $ha\ •lrl' et .....-.n, till• SHi•tJ wlabee 

•• peb\ n• tu• the AaeMla•t.ea bae •wl•td.nsl,. il'Plti-' _,,. ... 

tl• '" 1•• OtG ....... •eNri\J polletea 1a a ft.el.ti Tl'81 oo \1le 

u\l.eeal d.•t••• al• l• la&•••• l>)' S\a •fl\1Alif1•4 .. \i .. ot 

•oo..s.oat.S- ...... t.a Wt• t.llowiag •RUM••• 

le-.•• clay•• tN1ih of tbat. naHaion, a\rtetiy na•. 

fM enllll cetA1 or dpNra ••• b)" ov aawd teroae, tu .,.. ••• 

:l~ c.s.pi.l'M'fl.u, •• • .., oode• •za -td.l'Mr• litrelcea bJ ov U'JPHM• 

lyn1, tbe MU&pl NAl\DI Ina ..... ll'7P"analrd1 ... all tl\.•• 

•rop.el, lie ld.'ld.a t&o bM.wl• ot eowri.1Q' snter.u'iiCft. How.YW, 4'1le 

Lwcc&'f.a\loa t'Bsa=at to h«'f• O'hla'l.oolcd lMft th• tan - •lHti.a:t~ i\.-tM 

~lt.d.• al\il eaaea\£4 to 'b'* •r~• ... ~•• ~••ft sptUJltie, co•:.-.$ 

... ~t•1 'Gltis\al.7 Uri.YO b-• ~et.pl•• -uiU.• "ft .~ .. J.tt ll»'S "'-- - ....... ~ - -- ..... 

REF ID!~ti6773 

awe the aecuritJ ait.Wlt.ion "td.th respeot. ~o cm~oga~•i:·h1' 

1• o:oepUonallr reetr1et1ve t \ta Society teola thtlt it w.1rr1nte a 

.ftao'th•P atatent.n'I 

X-7 roaaona a~vate the crw~og.t'&pb1o eecurtty aitaa'ble\1 

iD. thia OOU1l{;1!."J • Clnet u.ndoubCGdly t la tho wn'M1i contusion beuwe.f:U 

baaio nelDU't•>~ qd tn.1bnoquo:at nau.lta wldr*' the SoQiety he.a triad t,.~; 

cl.ear l1P in 'thia atattament.. Ano1;her is th® faot. 'thl\t. t:hrc.mgb. the 

age• eryptog:t·l.lphie intoraatioo baa e.ollaia'tt\ntlJ \aun1 auppi-e1aed ....... 

p?"Obably beerr..t..~• ot tb.G very C('f3.fUa1on ex~lifto4 la the A44ool•ti.on •a 

ataiament. Ano~her 1$ the natu.~al aoluaiven&aa of th-9 prof~U.\01.cnals. 

Still a.nether 1 & 'the tra~tio ezpenenti~ - l!ll~ill &ll ~iGO mah in 

the m•or.r of mar or O!itl." oryptograph•r• ~'" o.t h.av1~ «n American ex• 

poae mt all. of h1£t om coutryta moi:rt ee:Ot:'•t ae"tivitiec in thin 

~i~ct, thit"bJ° l'Uiliing y-eara of work an the aolut.ion ~t mauy torolgn . . 

code•• Al...\ ot then fao'tora add up to tb qp&~ii!.l.ly heavy reoti.,...leo 

ti®• on tho tl'ee d1nttqsio!l ot e;-yptog:raph'f in t.M.;; OOl:t.~t,~J• 

Snob. a policy ia, in t.he 9Pinion of t...'l\e Soeiety 11 W'!W~"" 

alghted &' ben arJ.d U..'-a«JQlUiJOiOJtablf Unge:rma:t At l'l'.ll'Bt" :'i!ftZ1'& Na.eon~ 

point. 1u'i t!a1a ecnelu&d.ons. 

!ke ftra~ !$ th• ••t ol a;:"gUIO?tt$ fer let<-e ~.l':1.~gtlft:l,.; $~ 

ovi~y H.pletiw.a uva•io...S by ~.b• ABstaciat,~e-n iu S.'t-$ e't'.!tPe;P;iJ All 

the•• ar~u hold iln• tor errptt1g:-a~ a£ wll '44 !i.iJ..~ b~u!:!.1' 

at1atl.ft.• k.1t.owled.ge beb.~a. 1u1 ~!ll .~~~7 tt:q,~a~Mdt ·~ht\ l.attttt· 

.izu:ludaa :ihe 1\'n•%'• hnJilt4);'1, tho Si;'6lS.et7 we.iuld ~k~ ~11.eit th&. 

feolin(t ltffhi.W thQ A•ao•kt~.O".n' s ats.~li',,n1ts f'Jiatr th~ lllll't.c-iiritr p.N-£!,.1."'S-11.\ 

ulUm,•lY tbreo\orui t~do3 o.f' tnw~t., th~'f; it ia tlMtr'llo~x :t(J· ... 

~ Pt\91~t to ~'14~,n i~ale, ant! th~t i~_l.~ ~ol•~~t~d ~~ly.ba~$~~0 

11~ - .. 1\.. . . 

.il!'f:,tl';.l• 0'.1.ll.f'°A.1'?1J:'f'") I :~':o!)t I'~,- • ' '• • .y ' .",i,. -'' ,:, • ' • "• ~ , • . t ' 

~ 'I" _.-r-il ::;..;c ... ·:....•.OW • ' • ..._ • ~i-.. ,•· .......... ~~ -tl""'L-. .. .:..." _;.r.' •~.<;"i[:"' •tl(~11..,-ft.S.~%-~f"~~.1U~~'I - •"t'°•\·•! tl't'J• ~1t:'#t~J',.tJl• .J">:~-'#tjf=1.~)1_," 
~·!,----~-----------------.. ...._ ·e REF !£_;A66773 -

et ~e priaaes& Wt#ld. ~•u;ion. Ard.de fn• ~lo, th• Seo1e~y o~ •«• 

:U.ttil .. • to t.h.o A.11eoeia\icm '• •\&tanuilt b•7ond raaeirld~tg ~M' ftlle!.tle 

l'.rlt1o1a af!S eugpnton •uld pl'Obefbl'1 prove espeoi"llf tmtt..N. lu 

a ft.•l'-t wbiflb. ha• so long bten eeott'riff aad witMl"o.wn. 

Setoond.1.7, re•tric~n ti~ ceyptog...,aphie in.for1211Uon s\\mtt~ 

th• quallt7 and q~n~ity ot a!lllteta.r •l'JP~ogniphera •• & pl"imo eo~rct 

tor Qlf men •4 1deaa in thia ti.0ld. The &b.ortaight1td.nesa or tbla 

pol107 will !njve 11'h..1.s Dation, i.q>•roept.1W.y aa the flow f.4 MW Uf:~• 

atul taea alcn1l.J" <hi.es ViP • or trtght~nU\gl.y tJhen a fluci4on •bUiutS.on 

ealla 11\ vah\ tor erntogn.phe:;.~a.. C,.JPtognphe;:·a tWU\Qt b$ Utaine4 

ovam1P,\; b~ t.h&7 will b8. n•oded onraigbt.. Th'tAae •~ alNad1· 

lalcw aa~tiag about tho aubj•ot ttU.l be aTaUablo rn.r atl.r'i q.\d.ckl.7 

'lwl 'tht:t•• .mo .flllU5t be 'aught b-cm tha poUlld 1ap. Purth~:r-, th.cao 

aatn:ra will ha.Ye, boo.au• of '11.•ir b&eks,ft-41 ~' ter bott•l" wde~ 

aPD.diug fif ~he pnbleaa f'J£ prao1ti~a1 Ol'JPtoi~aPh::r than battily 

wara-tnuod aen. lota»11. aeaf"lJ au iap~t md~ p:rin~1pl.•• itt 

\ho tlol.4 atcm .from ft'$.tev invantics., 1iv.>Ii~&• J<!fJZter-eon ~ Bf'._, 

(d.!2.fl&\iODB 1°o31" a eipho~ ({pie• l'C) JtU1i •• llili~h' 11lf.g.h.t.ly •di· 

.Ulf4, i• •u.ll ued. b1 'i~o Armr• Sir Oharl&n ~e~t;;~t.(.)tl~; ti.be fl.U!lO\tlf 

_ Jb··~:t11h e&1entin11 cin.a,94 an :l.:llpa:lou f.r.tJP'tt1~ph- ~\~"\ * cl.~h""* IJYP. 

t.~1 se pod. 'Citiat the Bn.•11th UM4 it a.a a .f!.~ld ci~~\~ i\l W¢';!."!~ Wa:r. 

:i'8 Aa Aarien cleetrioal -.gu1eusr, Oilb&r' &. V•rnam> i.!t.vein.M4 c 

.~ .. tit t.olnyp.,.baee •d.phering•tnnsd.n•~ .. ofl: ~·tllumisa wee:ml'p-!lt>~ 

~day. To ••• a ~-1 troa 'ba~t~y, o Swedish ~oh.!mit:lil •• 

{ff.siffll' •&•tad Borie c. w. Hq4Pl.ia\ p:rodu• ao •eellcmt. a 4d.p.h-· R'1 ~Jlii~ 

tha\ bMl1 do.~a uod it. t1urhg Woflfi V~r n,,, 4\ld an Am•rieu j.:Mwtol!'" 

B-~~ a. ii•'b•~et, 4'.•Tol.c.a:p-4 a •1'7Ptegraph 'WlU..$1, ,!.~«:o'£'d.i~1...~ t.~* ~r, 

th• i•·r~;1\. uzll.1- ioir- t~p .... •etn't •~\c«iS.o:J~.. ill. e-t :~h.fJ..t.~ . . , . 

......... ~ -·.r.:-· 
. . ~ ' ~ . 

.. . ... ,, ,_,. 

e REF _ij2:A66773 e 

- itema e.mbod7 important oryp~graphio pl"inoiplosi all haYQ •uoceoeflill7 

Mt the t;eeb~ of pz'lllo't1oal uaageJ and all have been C".roated b7 araatCQXoryptogN.pherat ~- all 0£ l'.hiob atl'"ild.ngl.7 c Cllf'irw:.s the ~ortanoa ot~ 

amateur eon'tiI·ibutiona 'o c:ry1,tograyb.y. The go'Ve.ml!Obnt grabs £or the•• 

id•a•, bu.' unlfisely roJeot• calla tor hfll.p from possible contribQtoro. 

The populari -t:r of eryptog1"Uls in tb.'1 puzale pages of nolt.-spaparo illdi• 

ontee a ldde•?i·.ad intea-aat in tb1s au.bject, but thb go'fentrs•nt, in• 

etead. ot cl•v~::..c:pil'lg this poten~!.al. pOGl ot orypt.or;rapbera, actu.aJ.:1y 

bttata down it~ interest by oppr@1Hd.v• s•ourit.7 :r-egulationa. Unleso 

th1• policy it; chaug&d., what is nott toU1 may b~'10.11W $Uieide11-

11na1ly, the o.ftl.y mcde:nt authoritiGG en cryptogl"aphy who ~G'f• 

d1SC\UU1&d the llubject ot exo;Ja.aivo aeor(;Of both age~ thti~ sreat.e~ di._ 

aainstion ot C~1Jitog1~aphio intoril\lition bea'fl. Bervcs the natiw. 

The tlrn, Ge~m-al Marcel C.H:narge, ch16.f' o.f th• F:reneh ceyptograJ.ihio 

b11U"oau whoeH• va··k d.id m much tro h•lp win World. ~1· l,, atat•d !US faJ" 

back ~• 192) the~ 

' 

tttfoo mu·:.h 0#0:.re;;::7 is e~et.uea ha.~; 

llUpJ>~··as;!.cn 0£ cryptog:-apbio ut·Qi"raation 

NrNlta tn ~r~ lack of an 1n.fonw4 P•~ 

eoDael1 \:Jbi.\e pnblicatitJn of &~~al 41£~ 

f\ised :tm.oiHl•tl~ ot cert.au qua.1tions• S\l.M 

ea that ~•eming t.~•po!"i&ti1e.1l, dt,~3 

itot. px•el'O'G ~!:19 gfi.neral st.a.ff.· fitora eo!:i-.. 

eeel:t.ng d•t.P-11• o'E int..,reot 60 tJl:n !Ui.~~ 1' 

eryptf.\&r&phio £,1.\l"a&ue h\ 'Wo:d.d. Wil.X' I• rptana b; !lmd~wning ~x~s~t.tiv@ 

tsfl.Sr~q end. eoa.•l.,.li~s by 4e~l&ring 1;h\'t tl":e~'t ~t ru~~ti:!gX'.lphiC 

i~ol:'r.;ti..\tion is it1C1N~t.1al t.o • 1~ erypt..::tlJ."aph:l~ 11~nlc•.. Arter ~nl:v 

.rw1r •en•n.ta~ cf M~ 'M~!t, h11 ei:ayao 

.. 

:!""""· . 

\ ____ .]. )\ f I '/A' 

-----~ 
e REF-6!D:A66773 e 

"'lha't ia 1 the aacreq wM.oh enahroudGd 

al.moat; al). C1"'JPtograph1o aotivi.ties be!'or• the 

war h4• prov•d itNll to be a two-ed.pd. arword. 

The experl.encee ot ~he Woli..d War proved eonelu .... Id. vely that such aecrecy moat fraquently doaa 

11cre hal"ll than gcod. It'P prevent• t;be spreadirig, 

aong aold1era and oi TI.liana alike» of the gen• eral training 1n cryptography absolutely neceaee.ey for the conduct of modern wari'a.re. It. :re• 

a\rieta the horison of the 4)1•yp~ogra.phe:r and 

lulla him into G fallnciO'l~a oelf'•conaei~~~ 

Further on: "In b:t"i.af', all unnece1aa17 secr•oy ta to a high de~"ee 

obstructive ~ knowllfdg;S of 5td at;f'iciencr iri oryptogt\t.phyl 8 And .t.~'!;l 

tho tbird ot hia ooncludillg r~eommendat1one: QA maximum g&neral 

Jaund.&dgio ot b<r-th c:eypto.:p<apb.y and cryptanalysis, with th~ •l1mi..q_a~;t<.'?l 

ot all unneoe1iUMU"1 ecu:rr~cy f ab.ol.1.ld ~o ,g1 V&U to t..ll.:.~ Oor}'HJ ot o!t'J.c@:I:·/·~ '* 

Sutfu.t ~hea, nre the rea&Ql\8 lJtly ~M J$~ !$k Cipher Soci~l•J~ 

bel.1nea tha,. the prti5S$lt ovel'l7-reat:ricti1n• ~r.i'f·tographio .euurit1· 

pNgra.~ harms t.blii U9.t.ion. 'lhs Sodot)' tuls that libtt1~a1izati.or& oi:. 

•he p1 .. ogrrm atl:uw.ld l'ftak-9 a.vailabl~ more baA?ic 01··11.tographio bowllft.A·~ 

and should -~~.U.«'te publi~ inter••~ in OJ.7P~Ogrt.ph7 tiith~lii.t die• 

olo•!:lg an.7 ne(h'fitHse.rilJ'•tt«lC:""e_,. reaul:t.&..- '.fhi3 con b~J da.~u~ along 't~~­

l:lufu' laid ~~ by t.he ~;e~natiCG. !no~ha1~ wy w4?JJ.d b~ t.-c .-.lfli~'\~4 

eertatn otfic;:tel publii,'Sat.t:(.ene m crwtog1~ph:r ttl ·th$ pu'bli~~ fh~t1·=~ 

hooka contain noth!ng Jtb-.3ut o.f.ficial eiplte:r~ and. of£ero little i.f ./ 

iloweTwi tihe7 4°2r~ ~u-1a"it;ti$1-l ::; 

and ®mplote. "n4. they ocu.ld fill a pub.l.1¢ ~-.! wh\eth pr1vat.e 1.n• . ~~-. 

d-aatrrr doaa not til.\ (proeV1111P..l.7 beo.au.so \ht d.s..~ ta M .. ~1 •~ 

"• 

~ ~ 

$-

t.o be v.tlp?"Ofit,a~ltt). In o'&ba:r eoi•ncHu1, the ~~).'"l~tn~, ~iD:~.et).""Utt -.. -:ff,u 

·~ 

smc.\l & l'tl:f'~11Ah.ing ~r l~ti .... d~1ul but Uipor'ut a&t!arJ.i4.l. ~r. t~t ~utt-"":..J..'if.::,)~-

as OM r;,.~ its prl.~sry .ru1u2,'dousi :Sut in cn·ww~f'all)!',tp -·~· m' .f111ld vi.~~ 
RE[ ID:A66773 ~ -f... -

syatiom) a.r1·ord.ed the go\\"Gl"nJBelit an oppo1"tunit7 to downgr·~d• t.be se 

publioat1ona. Shmaehl.ly, itustead of ae1s1ug that ch1.\nOllt, the goverumont uaed tM ordor to upgrad• them, thua not only making th• U!l• 

n•u1esaarily hard go obtoin .fc.r thoae 1ntuaestcd reeaniete and. ad.J ..... 

it.a:ry personnel wtto h.at"a a rtgbt. to thea., but also removing them 

entirfJl7 trt>ill 'the t3duoatioua.l ap1'..area of the many ruuat.eur cryptog~a r.>he.r~ 

~ oo'i.lld therefrom ba:o~.fit thCtsteJ.ves and their eount.ry .. 

Thia whole :picture i~ not blaok, however. AL'lericsn Ct°J'"i~­

an.alytStll asi;onished. th.-.i world ~th th"'ir :tam<lus ;,x·tl~r eol.ution of ;::h!& 

Japanf!sa CO(b~. U~doub·:-..J.d1y th• level of the:l.1• «aeemapli~bm9ll"t rG!\£1·~·.,j 

high: certain hints le..11td .cred~n!:e to thi.u rtc-rw. w,1w·u""th~leaJt~ th@ 

lew Yol'k Cipher Soc:iety .fe!il.EJ ~h~ evan t.hi.e brillia..'l'lt wo.rit can bft 

extendiad and i.mprGno~, and t.J:k·:n. £t. leaat one -,ay ·r.o do it. we.1.ald be 

'to end the d.ang$l"ous preafi!S:t f·Oilf:'J Qf exossai Te aeercc7. 'lhu.a c~ 

the bclJt. 1nt.e1-~11ts ot ~.er1ca be 11utl'°"i(:td",