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. .> TOP 'SECRE,. 

Cbpy No. 8 

. LC${53 )/F/R 

tJX/US COMMUNICATIONS SECURITY CONFERENCE 1953 

Report of the Executive Committee 

to 

The Plenary Committee 

1.. . The Executive Committee of the UK/US Commtnlications Security Conference 

1953 have Completed their deliberations and have approved the detailed 

rep0rts of the various Sub-Committees. 

2. The Executive CoTIUilittee have drafted a report on the Conference, 

including the major recommendations, and this is attached hereto. 

3• It is recommended that 

j· 

(a) The detailed Reports of the various Sub-Committees be 

submitted to the U.K. Cypher Policy Board and the U.S. 

National Security Agency for approval and further 

action as may be appropriate. 

(b) The Enclosure be forwarded t~ the U.K. Chiefs of Staff 

and the U.S. Joint Chiefs of Staff for approval. 

dha1i'i1l8ll , Executive Committee 

. . 

PL 86-36/50 USC 3605 

Declassified and approved for release by NSA on 05-21-2014 pursuant to E.O. 1352e 

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LCS(53)/P/R 

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UK/US COMMUNICATIONS SECUaj:TY CONFERENC!E 1953 

REPORT 

TO THE U.K. CHIEFS OF STAFF AND THE U.S. JOINT CHIEFS OF STAFF 

1. In accordance with the agreement reached by the U.K. Chiefs of Staff and 

tne U.S. Joint Chiefs of Staff following the 1952 UK/US Communications Security 

Conference, the 1953 UK/US Comrrrunications Security Conference has been held in 

London; It was preceded by two weeks of informal discussions between u. K. and 

U.S. Engineering and Security experts. 

2. During the Conference the following subjects were discussed: 

a. Replacement of the ·existing Combined and NATO High Grade 

off-line general cryptosystem. 

b. Other off-line cypher machines. 

c. On-line teletypewriter 'cypher machines. 

d.. Speech security equipments. · 

e. Facsimile security equipments. 

t. Non-machine off-line cryptosystems including special purpose 

crypto-devices and systems. 

g. Transmission security, as distinct from cryptographic security. 

h. The security of non-communications transmissions, including 

navigational aids, IFF and data transmission. 

i. Crypto""lDaterial production equipments. 

3. The Conference included a full and frank exchange of views on all the items 

listed above, demonstrations of such equipments as could be made available and a 

number of visits to establishments engaged in research and development of 

oozmnunica.tions security equipment. 

4. During the course of the Conference, there were, as in 1952, independent 

disCl.15sions regarding the production of cryptoma.terial required for Combined and 

NA.TO communications. The allotment of tasks betweeil the U.K. and the U.S. was 

agreed and there was a valuable exchange of production techniques and procedures. 

There were also useful discussions, outside the Conference / of communica. tions 

procedures having security aspects and progress was made towards uniformity of 

p:rac:t;ice and improved security. 

5. The enclosed Reports of the various Committees which discussed the items 

listed in para.graph 2 above were approved by the Coni'erence and have been 

submitted to the U.K. Cypher Policy Board and the U.S. National Security Agency. 

/The 

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The highlights and major recommendations of the Conference were as follows:-

'~ ,~. 

a. Replacement of the existing Combined and NA.TO High Grade off-line 

general c;ryptosystem 

The U,K. have accepted the U.S. cryptoprinciple embodied in the 

.A.FS.AM 7, now in production in the U. s. A. The new U. K. off-line machine, 

at present in the development stage, will embody this principle but as 

the U.K. ma.chine is not expected to be in position before 1960, the 

U.S. will make available some 3,500 AFSAM 7 machines to the U,K. 

until the U.K. machine is available, and some 3,000 machines to other 

N&TO countries, probably in time to introduce this system for 

Combined and NATO communications by 1st July, 1956, The U.K. and U.S. 

security experts have agreed that the security provided by the 

existing LUCIFER system (CCM) is acceptable in the meantime. 

The Conference recommends that ultimately the cryptoprinciple emb~died 

in the AFSAM 7 should be adopted for Combined and NATO third level use. 

b. On-line teletypewriter cypher machines 

Operational demands for equipment of this kind are greatly in 

excess of its availability. The U,K, and U.S. have a very limited 

number of on-line equipments .in existence and others are in course 

of development. Long-tenn plans will aim at the maximum degree of 

standardisation, thereby reducing the lack of flexibility of 

communication8 and difficulties of maintenance c~used by the present 

situation, 

c. Spurious emissions which endanger communications security 

The Conference agrees that radiation, conduction and induction 

from communication and crypto devices are potentially grave sources of 

insecurity, This subject is receiving detailed examination by both 

countries, 

d. Speech security equipments 

No speech security equipments suitable for Combined and NATO use 

are available at present. The U.K. and U.S. have a nwnber of projects 

under development for strategic and tactical uses but as yet these have 

not been subjected to field trials, 

e. Facsimile security equipments (OIFi.X) 

The U.K. and the U.S. have specific projects for black/white 

CIFJlX under test but it is as yet too early to consider one to meet 

Combined requirements. 

As the CAN-UK-US JCFCs have already agreed ·chat multi-channel 

sub-carrier frequency modulation is the best method of transmission 

for CIFAX for other than short distance ground-wave HF radio links, 

the Conference recomm0nds that the Communications Equipment Panel of 

the JCECs be invited to agree a techni~~l specification for a multichannel SCFtiI transmissio~ system for Comb~ned use with CIFAX. 

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f. Transmission security 

The Conference was greatly concerned th.'3.t in peace time 

unclassified messages are transmitted in plain language by insecure 

means. Such messages not only lead to the revelation of intelligence 

but they tend to nullify the good that can be achieved by otherwise 

sound security I)ractices. This is true for two reasons: because 

compilations of individual unclassified items often provide 

intelligence of Secret or even Top Secret classificq.tion, and because 

plain language messages, related externaily to cypher messages, can 

jeo?ardise the security of the latter and of the address procedures 

employed with them. 

Other aspects of transmission insecurity were also examined, 

e.g. call signs, unchanging frequencies, external characteristics of 

encrypted messages. 

The Conference was aware of the serious operational difficulties 

involved in finding a solution to these problems and recommends that 

small Working Groups of,s0curity advisers and users should be set up 

by the U.K. and tho U.S. to study these problems and pro?ose their 

solution. The results should be exch:.'l.nged between the u.K. and the 

U.S. and, on the basis of these, Combined plans should be made. 

g. N~n-communications transmissions 

Neither the U.K. nor the U.S. cryptographic agencies were at this 

stage able to put forward any practical solution to the problem of 

providing security for such transmissions. It was considered that 

insufficient effort was as yet avai1able for detailed study, even on a 

theoretical basis. If this study is to be undertaken, additional 

personnel or an alteration.in priorities would be necessary. 

On the subject of the use of SIF with IFF' M'ark X, the Conferunce 

recommends that the attention of the C.il.l'f-UK-US JCECs should be 

directed to the fact that the security agencies of both countries 

agree: 

(1) that the present proposal for using SIF with IFF Mark X~with 

code-changing on Mode I is irrnecure as an identification system; 

( 2) furthermore, that the personal arid 'functional identities of 

Modes II and III could be a valuable source of intelligence to 

an enemy; 

(3) that the C.li.N-UK-US JCECs be invited to restate the security 

requirements for a system to opero te in conjunction with IFF 

Mark X. This specification should contain information about the 

degree of confidence in the identific~tion required, and the 

amount of risk which would be acceptable, 

(4) tmt when tho security requiremen·ts have been received f'rom the 

OJi.N-UK-US JCECs the cryptogra~hic agencies of the U.S. and the 

U.K. should make joint technical rroposals for a new and secure 

IFF system, 

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ho Weather Cry;Jtosystems 

The Coni'ercnce agrees that the CCM should be adopted as the 

off-line machine system requested in the NATO Meteorological Plan 

anu recommends that urgent action should be taken to secure 

acceptance through the CECS of the Standing Group with a view to 

placing the material necessary to implement the plan in position 

by the 1st May, 1954. Very early provision should be made to equip 

a key circuit with suitable t~letypewriter security equipment. 

i. Communications Security Development Programme 

The Conference considers substantial econonJiY' of development 

resources on both sides of the Atlantic could be achievecl if a 

clirectory were compiled showing the Combined and NATO communications 

security requirements and then a combined programme for 

communications security equipment were evolved from it. 

The Coni'erence recommends that the C. P. B. and N. S •. A. should 

prepare such a directory and progr11L11lle. 

j. Exchange of equipments and components 

The Coni'erence recommends that as a regular procedure each 

nation pr0viue to the other on an indefinite loan basis, for test 

and e:x:a.miriatio11, engineering and first production models of components 

and equipments of mutual interest; and that if exchange is no't 

practicabl.e the equipment should be subjected to an agreed series of 

tests in the parent country. · 

k. Effects of advances in electronics 

.Advances in electronics ·and circuitry will have a profound effect 

upon cry-.t_Jto-operations, supply and rnaintenan'ce as they are :Jractisd. 

to-day. For this reason, thought and planning by the Services are 

required now if they are to be in a ];!Osition to enjoy the full 

benefit af the advcmtages offered by electronic crypto equil_:irncnts 

when they become a,vailable. 

l. Co-ordinaticn of Cryptographic and Communic'ltions 

Equipment Deyelopment 

The pre$ent 9ractice of almost independent development of 

cr.fPto~raphiq equipment and certain forms of corrununiC'.ltions equi?ment 

has at times ,led to incompa'tibili ty of' one with the other. It is 

necessary that cry-~tographic equipment be dcsigneJ to suit the 

requirements 0f the communicitions system or, where necessary, the 

communications equipment and practices be adjusted .to make possible 

the utilisation of an acceptabl~ cr.YIJtogra~hic system, 

The Conference recoIIJinends that the necessary steps be taken to 

ensure that such c.::immunimtions security 11s is required should be 

considered at the tL-ne when the Ste.ff and Ope:::-at~.onal. Specifications 

ana/or Military Characteristics for communications equipment are 

being formulated, 

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Operating a.na Maintenance 

The development authority must maintain close co-ordination 

with the user Services so that the operating anQ maintenance 

requirements are made known ~t all stages in the development. Thus, 

users may weigh the need for the equipment against the maintenance 

and training requirements anl, if necessary, the development 

authority may adjust the design to meet the operating and 

maintenance problem. 

The Conf'erence recommends that there be consultation between 

the development engineers and the engineers and communimtors of the 

Services as early as possible in the process of development of each 

equipment in orJer to achieve these ends. 

n. Standards of-Security Requi~ements 

During the Conference the u. K. and U.S. security advisers 

i)repared. an agreed. methorl for the technical statement of security 

assessments of cry:-:'tosystems and the Services have .'.ld.opted a method 

of expressing their security requirements; these will be of mutual 

assistance in.deciding whether a proposed cryptosystem ai'fords 

adequate security. 

o. Future Liaison 

(1) Working Staff. The Conference recommends that there should be an 

exchange, on a semi-permanent basis, of working cryptanalysts 

an3. engineers from the research o.rnl development establishments 

of the two nations; and trot 'ietails should be worked out between 

CPB/GCHQ and NSA. 

(2) Visits. The Conference cec~mmends that the visits of engineers 

and security experts, independently of the Conferences, as 

already authorised ( 1952 Conference Report paragraph 11 e) should 

continue. 

6. Next Oonf erence 

The. Conference recommends that the next Conference should be held in 

Washington in September/October, 1954-, the prograrmne to be agreea. la.tar in the 

light of developments in the meantime. 

for CMirma.n, 

Cypher Policy Board. 

LONOON, 

10th November, 1953. 

I 

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PL 86-36/50 USC 3605 

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W.F~ Fried.man, 

Chainna.n, 

U.S. Delegation. 
REF ID:A522850 

Lds(53 )/F/R(Draft) 

UK/US COMMUNICATIONS SECURITY CONFERENCE 19.53 

Report of the Executive Committee 

to 

The Plenary Committee 

1. The Executive Committee of the UK/US Communications Security Conference 

1953 have completed their deliberations and have ·approved the detailed reports •' . ·. 

of the various Sub-Conunittees. 

2. The Executive Committee have drafted a :r"eport on.the :Conference, including 

the majof recommendations, and this is attached hereto. 

,3. It is recommended that 

(a) The detailed Reports of the various Sub-C0mmittees be 

submitted to the U.K. Cypher Policy Board and the U.S. 

National Security Agency for information and further 

action as may be appropriate. 

(b) The Enclosure be forwarded to the U.K. Chiefs of Staff 

and the U.S. Joint.Chiefs of Staff for ~pproval. 

PL 86-36/50 USC 3605 

Chairman, 

Executive Connnit~ee 

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I.CS{53)/P/R (Draft). 

Report 

to the· U.K. Chiefs of Staff ancJ. the U.S. Joint Chiefs of Staff 

of the UKJUS Communications Secl.ll'ity Conr"erence 1953. •. 

1. In their endorsement of the Report of the UK/US Oommunicatia:rl.s Security 

Conference which was held in Washington in Key/June 1952 .. the U.K. -Chiefs of 

Staff and the U.S. Joint Chiefs of ~taff ~reed t"hat .. r' · ., 

/ 

(a) The next Conference should be held in.L~ridon i:r:i !95.3. 

' '. / :.· ., . .• 

. . /. . . ·. 

(b) That a fortnight should be provideg/before ~he. c·onference opens /' . 

for discussions between U.K. an7 u~s. ~Engineering and Security 

experts for examination of eq..uipn'lentl/ abd '·:f~r visits to establishments. J 

/ 

(c) That the Conference itself/should be in the following two phases, . 

/ 

held concecutively: ; 1 

(i) Phase I: Prep~ion by the Engineering and Security experts 

of Reports and assessing equipments available Bnd 

under 

(ii) Meeting between·U.K. and U.s.·communications 

representatives of CPB and l.F'Si.C to examine and 

d fine Combined and NATO operati'onal requirements and, where 

,,. In 

informal discussions between U-.K. and U.S. Engineering arid Security experts •. 

!{• During tre~Conference the following subjects were discussed; 

a. Replacement of the existing_ Combined and N..1-l.TO High Grn.de 

off-line general.cryptosystem. 

b.· Other off-line cypher machines. 

c. · On-line teletypewriter cypher machines. 

d. Speech security equipments. 

e~ Facsimile security equipments. 

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f. Non-machine cff-line cryptosystems including special 

purpose crYPto-devices and systems. 

g. Transmission security, as distinct from cryptograrhic 

security. 

h. The security of non-communications transmissions, including 

navigational aids, Ili'F and data transmission. 

-~ Crypto-material pro~uction equipments. 

~)itepcrts of the various Committees wh;\ch discussed t~t,;;Q'., listed in 

paragraph~above l have'~en/\submihed ~~~'-·~-~--~- to thJlu~rCl~ypherPolicy -~ Board and the 

U.S. National Security Agency for inf;:.rmation and further action as may be 

"P;"."priate~ i-u·t°'~ - r· . zl~ - :i. The Conference included a full and frank exchange of views on all the items 

listed, demonstrations of such equipments as could be ma~e available and a 

number of visits to establishments engaged in research and dev.elopment of 

com.rnunications security equipment. 

,...sf-. During th~ course of the Conference, there were, as in 1952, independent 

discussions rep:arding the production of cryptcmaterial required for Combined and 

NATO communications. The allotment of tasks between the U,K~ _and the u.s. was 

agreerr and there was a valuable exchange of production techniques and procedures. 

There were also useful discussions,, outside the Conference, of communications 

procedures having security asp~cts and progress was made towards uniformity of 

The highlights and major recommenilations of the Conference were as follows:-

• 

a. Replacement of the existing Combined and Nid'O High Grade off-line 

,,• 

general cr;yptosystem. · ·~~~~"1<1 The U.K. have accepted the U.S. -ijlelfll3 cryPtoprinci1:',le,. now in ;:iroduction 

in the U.S.A. -ea=fl'li 'M i:ijl;; The new U.K. off-line machine e.t present in the 

development stage will embody this .principle but as the U.K. machine is 

not expected to be in position befcre 1960, the U.S. will make available tcc 

the U.K. cm-l:S~:i:t;:iz:~11·:~liH· the u_.~~hine is available, some 3,5QO 

- a:.i,._!..~-N~To~- a.k-o~ 

~,SAM 7 machines~rcb~ly in time to introduce this system for Combined 

and NATO communications by 1st July, 1956. Th~ U.K. and U.S. security 

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e.xr:.erts have o.greed that the security provided by the existing 

WCIFER system (COM) is acceptable in the meantime. Th~ u .• K. and 

~ 1'ttl-fli•t·'T~~~~~~A~tY U.S. also recommend tha~ultimately I\ 1:-he,. ~.1iesye1iel'l'I shoul.i ··7 

be adopted for Combined and Ni.TO ~~9'lon use. 

(b) Low echelon machine external nower su~Dl • 

The u.K. and the U.S. a0ajo~requirement for a 

ffil:\.C~equiring no ~~~~ .... ~, ower· s~ for Combined and Nb.TO 

~-•J!li«l81l use~ the There is no machine 

presently which will m this requirement but the D.17 

now under opment by the U,S. a possible ultimate 

solutio • 

cb) On-line teletypewriter cypher machines •. 

Operational demands for equipment :if this kind are greatly in 

excess of its availability. The U,K •. and U.S. have 

a vecy limited number of on-line . ~-U in existence and others 

nre in course Of development. ... •as. ~Oi&i£t 1 Hat!;§ afe OatJAbie Of 

r 

~iP'A''ifricii1"1eJ Dffi11g be h;;EB;p911'1e11::t ? OS ie;R i:iiQ ;i,t. ifJ S'2 =I II er.I :'I f"g Z 

term plans will a:im at the maximum degree of stanr'l.ardisation,. 

thereby reducing the lack of flexibility ·of communications anC. 

diffieulties of ~aintenence caused by the present situation, 

(t) S urious emis·aions which enr:lan ,er communications securit • 

~he H.K. an. d the u.s •.. agr~e that radiation,. conductio~lle..Pu 

mduct~gg from communication and crypto devices ar~ gra-:::e- \ 

jv'ah ~ ~ources cf insecurity. This. subject .is receiving detailed 

examination by both countries. 

Speeoh security eguipruents. 

No speech security equipments suitable for Combined and NATO use 

are available at present. The lI.K. and U,S. have a. number of 

p~ojects under development for strategic and tactical uses but as 

yet thes9 have not been subjected to Field trials~ 

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~ Facsimile security equipments (CIFAX) 

The U .K. and the U .s. hn.'V'e specific projeots for black/white 

CIFAX under test but it is as yet too early to ccnsi'ler one to 

meet Combined requirements~ 

As the CAN-UK-US ·JCEOs have already agreed that multi-channel 

sub-carrier frequency modulation is the best method of 

transmission for Cil1ilX for other than short distruices groundwave HF radio links, it is. recommended that the Conmiunicaticns 

Equipment Panel of the ~C Cs a technicE..l 

J snecification fo a multi-·ch .. . -1t s_ stem for 

Combined use with CIFA.X • 

.. (g) .;.,o,;;;.;;.;;....;===-.;;.....~..:;.;;;~--....;..;...;:;.;;,c;..;.~~~=~ 

its 

. ~ Transmission security. 

The Conference was i:·ree..tly concerned that unclassified. messages 

in peace time are transmitted 

the 

practices. reasons: compilations of 

individual 

language 

messages, can jeopardise 

Other aspects 

the lattera..J- ~ ~ ~~e,:. 

of transmission insecurity were also examined, 

e.g. call signs, unchanging frequencies, external characteristics 

of encrypted messages. 

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The~~ "* ,o rTccmme~that -5- e ~ m small Worki~g 

Groups of security advisers .and usersf!:o s':11ilhhese ~ ond 

propose their solution. The results should be exchanged.between the 

U.K. and the u.s, anrl, on the basis of these, Combined pl8lls shoulfi be 

made, 

Non-communications transmissions, 

Neither the U.K. nor the U.S. oryptogr hie agencies were at this 

stage able to put-forward 

providing security for s It w considered that 

insufficient for etailed study, even on a 

If this study is undertaken, additicnal 

perso an alteration in prior.· wc:uld be necessary. 

On the subject cf the use of SJlt1 with Il""'F Mark X, it is recommended 

that tlie attention of the C.AN-UK-US JC~Cs should be directed to the 

fact that- the security agencies of both countries agree: 

(1) that the present proposal for using SIF with H'li' Mark X, with codechanging on Mode I is insecure as an identification system; 

(2) furthermore. that the personal and functional identities of 

Modes II and III could be a valuable source sf intelligence to an 

ene!J\Y; 

(3) that J.O • .E.C. 's be inviterl to restate the security 

requirement or a system to operate in conjunction with I.:b\:b1. lVIk. X, 

This ificat1on shoul~ntain infonnation about the degree of 

dence in the identific~t~?n required, and the amount of risk 

(4) that ·l'ffien the have been received from the 

c,·\N-U".l{-US vtographic agencies of the U.b •. and the 

U.K. make fer a new and secure I.:141

.1''. system• 

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(a) That if\ossible.it 

\ 

' transponc1e~unit •. 

' ' (b) That if (a) ab v 

conjunction 

Weather oryptosystems, . 

this is 

they s houlcl, in 

agencies, 

the requirea. 

with its 

· .. advisable, 

The U,K. and U.S. have agreed that the COM should be adopted as 

the off-line machine system requested in the N.ATO Meteorological 

Plan and it is recommended that urgent action shoulcl be taken to 

secure acceptance through the CECS of the Standing Group with a 

. view to placing the material necessary to implement the plan in 

position by the 1st May, 1954. not all the 

on-lina teletypewriter security supplied 

by that equin the 

Shaula. an 

immediately offer 

1 until t-he . • M.(s· . ~.,,~~.es 

:iJt1 i:t is thought that oonsiderable econo'1\Y of development res01~ 

&"/~o~d~{ihe~lantic ~ ~~~ ~-:1 i'W '!!b.:plle~f<Ji. the Com/::f and NATO co!ru:lJ,i:,"~seourity ~ 2 

requirements .. sna ~ orypto,-sraph~qnipments or systems shoulrl l:lo ':> 

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such 

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each nation 

for test and 

examination engineering 

oomponents and equipmen and that 

if exchange is not 

parent country. 

~ .a!L ~cw_, 1.11. 

will have a - ~-7 

electronic crypto quipments when they become 

av · ~ble. 

J2, Co-ordinaticn of Cry-Jtogranhic ·and Co1mnunications )'>'-- !guipment Development. 

The present practice of almost independent development of 

cryotographic equipment and certain forms of communications 

a)r~ equipment has .. !iF!m«My leJ tc incompatibility of one with the 

other. In order that compatibility !!:_8Y be achieved i 

essential 

""1?ffll i & r* at 

c o!Tl!Ilunic at icns 

and nra.ctices ~ be adjusted to the 

It the ~ecessary steps be taken to 

ensure action is ~dsri;~ ~ 811 ee11eeP~__. 

/Operating 
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M Operating and Maintenance. 

The development authority must maintain close co-ordination 

with the User Services so that the operating and maintenance 

It is recommended that there be consultation between the 

development engineers and the ~ervice engineers and 

communicators as early as possible in the Drocess of develo~ment 

of each equipment in order to achieve these ends. 

~ S1umdards of Security Reguirements. 

During the Conference the u.K. and U.S. security advisers 

pre~ared an agreed method for the technical statement of 

security assessments of cryptosystems and the .:::>ervices have 

adopted a method of expressing their security requirements; these 

will be of mutua.l assistance in deciding whether a proposed 

cryptosystem affords adequate security, 

~) Future Liaison.· 

( 1) IVorking Staff. It is recommended that there should be an 

exchange, on a semi-permanent basis, of working cryptanalysts 

and engineers from the research and aevelopment establishments 

of the two nations; and that details should be worked out between 

OPB/GCHQ and NSA,. 

(2) Visits. It is recommenrred that the visits of engineers and 

security experts, independently of the Conferences, as already 

authorised (1952 Conference Report raragraph 11 e) should 

continue. 

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j. Next Conference. 

It is recommendedt 

That the next Conference should be held in Washington 

follows:- ~~~~to~~~ o·· 

' 

Departments, Development ., h such security advisers from 

mey be priate to inspect and discuss 

Operational~the Oervioe Departments 

representatives cf C.P.B. and ntS:A. to define Combined and 

NATO Operational requirement and, where possible, to recomr:oencl 

equipments to meet the 

,,::: ?· 

PL 86-36/50 USC 3605 

cnarrman, 

Cypher Policy Board. 

TOP SECREJ 

W •It'. 1'1r:iedman 

Chairr.ian, 

u.s. Delegation.