Lecture Notes on The Code Book by Simon Singh

... for the class
Codes, codemakers, codebreakers: an introduction to cryptography.
[Stuff inside square brackets is not in Singh's text.]

extra stuff

  • sequential homophonic cipher
  • black chamber day
  • black chamber day: 1918
  • black chamber day: 1860
  • black chamber day: 1918
  • black chamber day: 1942
  • black chamber day: evolution of one-time-pad

    • context for reading this book

    Introduction to The Code Book by Simon Singh

    Cipher of Mary Queen of Scots

    Evolution of Secret Writing

     
     a b c d e f g h i j k l m n o p q r s t u v w x y z
 1 0 2 1 6 1 0 2 2 0 0 1 1 3 3 1 0 3 4 3 0 0 0 1 0 0
    how many rearrangements of a 1-2-1-6-2-2-1-1-3-3-1-3-4-3-1 multiset?
    35! / (1! * 2! * 1! * 6! * 2! * 2! * 1! * 1! * 3! * 3! * 1! * 3! * 4! * 3! * 1! )

    encryption/decryption

    transposition cipher

     
    s    e    n    d    m    o    r    e
\t   \r   \o   \o   \p   \s   \t   \o
 \s   \o   \u   \t   \h   \e   \r   \n
  \f   \l   \a   \n   \k   \x   \q   \i

stsferolnouadotnmphkosexrtuqeoni

    r    i    f    n    e    i    h    r
\   /\   /\   /\   /\   /\   /\   /\
 \a/  \l/  \e/  \c/  \c/  \p/  \e/  \

rifneihraleccpe

    substitution cipher

     
    abcdefghijklmnopqrstuvwxyz 3-shift Caesar cipher
DEFGHIJKLMNOPQRSTUVWXYZABC 3-VKLIW fDHVDU FLSKHU

    abcdefghijklmnopqrstuvwxyz how secure is this?
MARYQUENOFSCTVWXZBDGHIJKLP NWJ DQRHBQ OD GNOD?

    Arab cryptanalysts: linguistics, statistics, religious devotion

    cryptanalysing a ciphertext

     UANQ PILDNDC, PF HNC OANBS (T CNLB) SNS TQM THIVU PF OLFJUICLTJAF OBTQQ. N QTNS UATU FIV TBB PVQU SI T UANLUF YILS QUILF YNUAIVU VQNDC T JTLUNOVBTLBF OIPPID YLNUNDC QFPHIB (N'P AIJNDC UATU FIV CLTQJ YATU N'P QTFNDC). QI PF HNC OANBS TDS PF QPTBB OANBS (TBQI T CNLB) QUTLU UANQ UTQM LNCAU TYTF.

    English history

    renaissance in the west

    Babington plot

    le chiffre indéchiffrable

     
    W H I T E W H I T E W H I T E W H I T E W H I
d i v e r t t r o o p s t o e a s t r i d g e
Z P D X V P A Z H S L Z B H I W Z B K M Z N M
    cj = ( pj + kj mod κ ) mod α

    shunning Vigenére to Man in Iron Mask

     
    a     09 12 33 47 53 67 78 92
b     48 81
c     13 41 62
d     01 03 45 79
e     14 16 24 44 46 55 57 64 74 82 87 98
f     10 31
...   ...
x     28
y     21 52
z     02

    Antoine/Bonaventure Rossignol

    black chambers

    Babbage v Vigenère

    agony columns to buried treasure

    Beale saga

    mechanisation of secrecy

    Polybius

     
       1   2   3   4   5
1  a   b   c   d   e
2  f   g   h  i/j  k
3  l   m   n   o   p
4  q   r   s   t   u
5  v   w   x   y   z

    23 34 52 24 43 44 23 15 35 34 31 54 12 
24 45 43 22 42 24 14 45 43 15 21 45 31 
24 33 44 15 31 15 22 42 11 35 23 54  ?

   1   2   3   4   5   6
1  a   b   c   d   e   f
2  g   h   i   j   k   l
3  m   n   o   p   q   r
4  s   t   u   v   w   x
5  y   z   0   1   2   3
6  4   5   6   7   8   9

    Playfair cipher (Appendix E)

     
       C   H   A   R   L
   E   S   B   D   F
   G  I/J  K   M   N
   O   P   Q   T   U
   V   W   X   Y   Z

plaintext:   retreat left          ??????????

             re tr ea tl ef tx     ?? ?? ?? ?? ??

ciphertext:  CD YD BC UR SE QY     BC DW UP PF GC

    LP YN UG DZ UC PA DS OT MS AE SE CU DH NK BU UC ES TG YD

    ADFGVX cipher (Appendix F)     . _     _ . .     . . _ .     _ _ .     . . . _     _ . . _ 

        A D F G V X
A   8 P 3 D 1 N
D   L T H O A H
F   7 K B C 5 Z
G   J U 6 W G M
V   X S V I R 2
X   9 E Y 0 F Q

keyword: CUBE       

c  r  a  c  k  e  d  b  y  ?  ?  ?  ?  ?  ?  ?  ?  ?  ?  ?  ?  ?  ?

FG VV DV FG FD XD AG FF XF ** ** ** ** ** ** ** ** ** ** ** ** ** **

C U B E  => B          C           E          U

F G V V      VFXF*******FDFAX*******VGDF*******GVDGF*******
D V F G 
F D X D 
A G F F 
X F * *
* * * * 
* * * *
* * * *
* * * *
* * * *
* * * *
* *

    ADFGVX cryptanalysis

     v d g g f x x g g d d v d f g g d g g v d d f d x d d v v v d d f x a g a a a x 
    v d d d
d v d d
g d f f
g f d x 
f g x a
x g d g
x d d a
g g v a
g g v a
d v v x

    grid: see Appendix F    keysize: 4 
VFXFGDGVDAVFDFAXXVXAVVAVGDFVGVDVXGGVDGFDVDDGFX
----------------------------------------------
perm? was 1234?  e.g. keyword ARTY
12 chars     12 chars     11 chars    11 chars
VFXFGDGVDAVF DFAXXVXAVVAV GDFVGVDVXGG VDGFDVDDGFX

VDGVFFDD ... => s g b t ...   :(
----------------------------------------------
perm? was 1243?  e.g. keyword ARTS
12 chars     12 chars     11 chars    11 chars
VFXFGDGVDAVF DFAXXVXAVVAV GDFVGVDVXGG VDGFDVDDGFX

VDVGFFDD ... => s i b t ...   :(
----------------------------------------------
perm? ...  
                               :(
----------------------------------------------
perm? .... was 3142? e.g. keyword CUBE
11 chars    12 chars     11 chars    12 chars
VFXFGDGVDAV FDFAXXVXAVVA VGDFVGVDVXG GVDGFDVDDGFX

FGVVDVFG ... => c r a c ...   :)

    Zimmermann affair

    holy grail: 1-time pad

    evolution of 1-time pad

     
    D D D D D D D D D D D D
c a e s a r c i p h e r 
F D H V D U F L S K H U 
abcdefghijklmnopqrstuvwxyz
DEFGHIJKLMNOPQRSTUVWXYZABC

abcdefghijklmnopqrstuvwxyz
BLIZARDWNGHJKMOPQSTUVXYCEF
k e y p h r a s e s u b s t i t u t i o n c i p h e r 
H A E P W S B T A T V L T U N U V U N O M I N P W A S

S E C R E T S E C R E T S E 
v i g e n e r e c i p h e r 
N M I V R X J I E Z T A W V 

A N H I S T O R I C A L I N T R 
r u n n i n g k e y c i p h e r 
R H U V A G U B M A C T X U X I 

Q T X P L K G G U R E M P D W X 
o n e t i m e p a d c i p h e r 
E G B I T W K V U U G U E K A O

    equiprobable keys, equiprobable plaintexts

     
    ?  ?  ?  ?  ?  ?
?  ?  ?  ?  ?  ?
C  T  F  Q  Q  R

C-H  T-E  F-L  Q-P  Q-M  R-E    C-G  T-O  F-A  Q-W  Q-A  R-Y
 h    e    l    p    m    e      g    o    a    w    a    y
 C    T    F    Q    Q    R      C    T    F    Q    Q    R

    reuse of 1-time pad: appendix G

    cipher machines -- cipher discs to Enigma

    cracking Enigma

     
     V E C J I B    rotors 123, start DDN
 E W O P F A
 K D A L Y T    1-4:
 L C V T E O    A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
 B A H Q D Z                                              J
 J Y S I B Y
 T I Q W V P
 Q X E Y R Q
 P G Y F A V    2-5:
 F Q P A L R    A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
 C R M U Q N            I                                          
 D U R C J M
 Z Z K N U L
 Y O U M W K
 X N B S S D    3-6:
 I T J B T G    A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
 H J G E K H        B
 U K L V H J
 W V F O O U
 G P X D P C
 R L N K M S
 A S D R G I
 S B Z G N X
 O H T Z Z W
 N F I H C F
 M M W X X E

    Poles pass baton ...

    geese that never cackled

    Alan Turing

    Rejewski and Enigma

    Turing and Enigma

    Bletchley Park

    Turing's crib circuit method (assuming no ring)

    deduce plugboard settings

     
    ...wettervorhersage........
KVBVRBCPZFQFNTTQEQOGYIIOYNG

    kidnapping codebooks

    anonymous cryptanalysts

    why war?

    Ch 5: language barrier

    Navajo code talkers

    decipher lost languages

    deciphering linear B

    Alice and Bob go public

    God rewards fools

    birth of public-key cryptography

    prime suspects

    alternative history of public-key cryptography

    binary numbers

    Diffie-Hellman-Merkle key exchange

    DHM correctness

    DHM efficiency

    DHM security
  • how hard to "undo" exponentition, i.e. find e s.t. a**e %n = x ?
  • discrete logarithm problem
  • as far as we know: slow ...   try each possible exponent

    DHM example

     
    p            = 613144603035200518605071627722399281527
base         = 347449578131074797459449734586666998031
alice_secret = 474140564715023867271727810192114419457
bob_secret   = 556327197178837163583577967104054021837

alice_sends  = pow(base,        alice_secret, p)
bob_sends    = pow(base,        bob_secret,   p)
alice_key    = pow(bob_sends,   alice_secret, p)
bob_key      = pow(alice_sends, bob_secret,   p)

Alice,Bob probable prime 613144603035200518605071627722399281527
Alice,Bob base           347449578131074797459449734586666998031
Alice sends Bob          344627486120828843474388906075377334410
Bob   sends Alice        409706635860222822429885047531176332371
Alice creates key        450786317947341275948138905696766128062
Bob   creates key        450786317947341275948138905696766128062

    Alice and Bob find a large prime how?

    Fermat's Little Theorem

    probabilistic primality test

    Euler's Totient Generalization

    Euclid's Greatest Common Divisor

     
       Euclid gcd: compute gcd(a,b), a= 60534384   b= 35717371
   gcd is last non-zero remainder
60534384 - 35717371 * 1 = 24817013
35717371 - 24817013 * 1 = 10900358
24817013 - 10900358 * 2 = 3016297
10900358 - 3016297 * 3 = 1851467
3016297 - 1851467 * 1 = 1164830
1851467 - 1164830 * 1 = 686637
1164830 - 686637 * 1 = 478193
686637 - 478193 * 1 = 208444
478193 - 208444 * 2 = 61305
208444 - 61305 * 3 = 24529
61305 - 24529 * 2 = 12247
24529 - 12247 * 2 = 35
12247 - 35 * 349 = 32
35 - 32 * 1 = 3
32 - 3 * 10 = 2
3 - 2 * 1 = 1
2 - 1 * 2 = 0

   extension: express gcd as linear combination of a,b
1  =  3 * 1  +  2 * -1
1  =  32 * -1  +  3 * 11
1  =  35 * 11  +  32 * -12
1  =  12247 * -12  +  35 * 4199
1  =  24529 * 4199  +  12247 * -8410
1  =  61305 * -8410  +  24529 * 21019
1  =  208444 * 21019  +  61305 * -71467
1  =  478193 * -71467  +  208444 * 163953
1  =  686637 * 163953  +  478193 * -235420
1  =  1164830 * -235420  +  686637 * 399373
1  =  1851467 * 399373  +  1164830 * -634793
1  =  3016297 * -634793  +  1851467 * 1034166
1  =  10900358 * 1034166  +  3016297 * -3737291
1  =  24817013 * -3737291  +  10900358 * 8508748
1  =  35717371 * 8508748  +  24817013 * -12246039
1  =  60534384 * -12246039  +  35717371 * 20754787

    RSA

    pretty good privacy

    pgp features

    DH digital signature

    simple signature example (use RSA, ignore hashing)

    pgp protocol (roughly)

    encryption for the masses ... or not

    a quantum leap into the future

    future of cryptanalysis

    quantum mechanics

    quantum money

    quantum cryptrography

    Bennett-Brassard qc protocol

    Bennett-Brassard qc security

    quantum computers

    so-called bible code

    some 20C discrete math

    index of coincidence

     
    { a,a,a,a,b,b,c,d,d,d,e,e,e,e,e} ? 

I_c  =  (4*3 + 2*1 +  1*0 + 3*2 + 5*4) / (15*14)
     =  (12  +  2  +   0  +  6  + 20 ) /  210 
     =   0.19...

{ a,a,a,b,b,b,c,c,c,d,d,d,e,e,e } ? 

I_c  =  (3*2 + 3*2 +  3*2 + 3*2 + 3*2) / (15*14)
     =  ( 6  +  6  +   6  +  6  +  6 ) /  210 
     =   0.14...

I_c  =   ( f_1*(f_1 - 1) + f_2*(f_2 - 1) + ... + f_c*(f_c - 1) / n*(n-1)

if n is large,  (f_j - 1) / (n - 1)  ≈  f_j / n   =   p_j,  and so

I_c  ≈ p_1^2 + p_2^2 + ... + p_c^2

    index of mutal coincidence

     
    { a a a a      b b     c  d d d  e e e e e } and
{ a a a a a  b b b b  c c   d      e e e   }  ?

I_mc = (4*5 + 2*4 + 1*2 +  3*1 + 5*3) / (15*15) = 
     =  48/225 = 0.21...

{ a a a a   b b   c   d d d   e e e e e } and
{ a a a a   b b   c   d d d   e e e e e }  ?

I_mc = (4*4 + 2*2 + 1*1 +  3*3 + 5*5) / (15*15) = 
     =  55/225 = 0.24...

    Friedman IC and IMC method to crack Vigenère cipher

     fake example: consider 5 character alphabet with typical frequencies below, and ciphertext substring frequencies (a bbb ccccc dddd ee). which shift gives best IMC? 
     a    b    c    d    e
.27  .13  .07  .20  .33

shift 0    a->a    (a bbb ccccc dddd ee)
((1*.27) + (3*.13) + (5*.07) + (4*.2) + (2*.33))/15 = .165

shift 1    a->b    (aa b ccc ddddd eeee)
((2*.27) + (1*.13) + (3*.07) + (5*.2) + (4*.33))/15 = .213

shift 2    a->c    (aaaa bb c ddd eeeee)
((4*.27) + (2*.13) + (1*.07) + (3*.2) + (5*.33))/15 = .244

shift 3    a->d    (aaaaa bbbb cc d eee)
((5*.27) + (4*.13) + (2*.07) + (1*.2) + (3*.33))/15 = .213

shift 4    a->e    (aaa bbbbb cccc dd e)
((3*.27) + (5*.13) + (4*.07) + (2*.2) + (1*.33))/15 = .165

    IC and Vigenère cryptanalysis

     
       a       b       c     ...      z
 .081    .019    .028           .001
 .0066 + .0004 + .0008 + ...  + .0000  =  .065...

    SAABTFWFTBJVAKLGCZSRVVAHCMBEHNQIFIAWNA
FGZMIOFUIZPRKCZUSGZFCQSGFVRFWFSFGNFVRV
WQGAGBIWYDAAIAVIEHUWLASFLWPOLQWGQNFAUB
TXWDHUWEUZYTMFVNLEMGJSTFYRDTK

keysize 1 ?
  substring S A A B T ...
  I_c = .050

keysize 2 ?
  substring S A T W T ...
  substring A B F F B ...
  avg I_c = .053

keysize 3 ?
  substring S B W B A ...
  substring A T F J K ...
  substring A F T V L ...
  avg I_c = .054

keysize 4 ?
  substring S T B K Z ...
  substring A F J L S ...
  substring A W V G R ...
  substring B F A C V ...
  avg I_c = .046

keysize 5 ?
  substring S F J G V ...
  substring A W V C V ...
  substring A F A Z A ...
  substring B T K S H ...
  substring T B L R C ...
  avg I_c = .070

keysize 6 ?
  substring S W A S C ...
  substring A F K R M ...
  substring A T L V B ...
  substring B B G V E ...
  substring T J C A H ...
  substring F V Z H N ...
  avg I_c = .043

    counting plugboard pairings

    cycle decompositions (for Rejewksi signatures)
  • how many cycle decompositions of a 26-permutation ?
  • how many ways to sum to 26 ?
  • how many partitions of n=26 ? 
     n   p(n)
 1    1       1
 2    2       2 1+1
 3    3       3 2+1 1+1+1
 4    5       4 3+1 2+2 2+1+1 1+1+1+1
 5    7       5 4+1 3+2 3+1+1 2+2+1 2+1+1+1 1+1+1+1+1
 6   11       6 5+1 4+2 4+1+1 3+3 3+2+1 3+1+1+1 2+2+2 2+2+1+1 2+1+1+1+1 1+1+1+1+1+1
  
...
    
26  2436

    prime factorization

    recognizing the running key cipher

    #!/usr/bin/env python
# show single letter frequencies of running key cipher,
# assuming both key and ptext independently uniformly sampled from 
# typical English letter single letter frequencies
import string
L = [ # English letter frequencies
 8.167, 1.492, 2.782, 4.253, 12.702, 2.228, 2.015, 6.094, 6.966, 0.153,
 0.772, 4.025, 2.406, 6.749,  7.507, 1.929, 0.095, 5.987, 6.327, 9.056,
 2.758, 0.978, 2.360, 0.150,  1.974, 0.074 ]

def printAlphabet():
  alphabet = string.ascii_lowercase
  for letter in alphabet:
    print ' '+letter,
  print ''

def showAsPerCentRatios(A):
  for j in range(len(A)):
    print "%2d" % int(round (100.0*A[j]/(1.0*sum(A)))),
  print ''

def runningCipherFreqs(L):
  M = [] # running cipher frequencies
  n = len(L)
  # compute M
  for j in range(n):
    s = 0.0
    for k in range(n):
      s += 1.0*L[k]*L[(j-k)%n] # ptxt k + key (j-k) = ctxt j
    M.append(s/sum(L))
  return M

printAlphabet()
showAsPerCentRatios(L)
showAsPerCentRatios(runningCipherFreqs(L))
---------------
python < run_ciph_freq.py 
 a  b  c  d  e  f  g  h  i  j  k  l  m  n  o  p  q  r  s  t  u  v  w  x  y  z 
 8  1  3  4 13  2  2  6  7  0  1  4  2  7  8  2  0  6  6  9  3  1  2  0  2  0 
 5  3  3  3  5  4  4  5  5  3  4  5  4  3  3  4  3  4  4  4  3  5  5  4  3  4

    sequential homophonic cipher

     
    s*iqq4epdwvjg3oh2#*3z,5e'9icmsw3qtg0r*s/t9%+mes%bvpwhxlat*&1ke'
wi3g.h26uvu4'-zk*s9+qei5rwxjh3,)ba't.*%clq)u0e(4#m,doksg&k1/2uib(
6w5paxu3.5r9sz-t*hc0jenomx2l4s1#zgk93wcm-'3jid,8ubh0uyo'6g&59(*d2a/&
r.+4kzi,t1p%beh(cla3m0q-k6gdkj#.kw2r4/&*'xzo1$uyl9(p,dm5bi3aec
&u+%gnwh(9d+*'xi.e#36w/%4&0-h(ju2r3*po+m'e
zlgd9&%wi5m(*n,#qdghvu+e/1'b9c3-i&m(0djk%g2z+a.%&4c6wh0r,(b*
de'xwi59&*)ou2zlpa.sm+4(%1hvgcd)#,ex06w2'-yj9izbf3a.5&*8ue/c4p
okwsm+,g09(dby*#e2axk/1szr.swmh%*'5)qe&3wp34+qy,#3bycg)%a3/.4$
-j!9ivm0(t*q2lpouv6etg+x,#hbd&1k/a.5(w'xd%9s4*ken-pmz,#b&j/cok
0raswp(l6.i2r4n,vbz*cg1heds9vl0)a&uyy-(.5md&3w'2j#*z+4e(c
xtw/kgd6io0p,b&1k*hqsev'92u5aw#.z-)4(,biha*/cr.t4d0,p'bf2#asmzq
tl./4kjpcsou%0#g,&2eix(wh5t6b/a*p.d1s4s9&,#e)+bk/wsa)um%xg'v(
z.i*hc45xup9'vduss,#)q0rbkuvm2gna&k/-s3lep+.(zji5udcwhxk4n,#s*q
)bkou'59ixa.5064)/m&2%qye+s,zc1)u02rbtl-%ag(+whxt9z6cr.
4f3,y0mj'ok2lgdtb&zapiy19hc*'5e%mi.-k6w#xtrg04),*3ljh26b
(ae3owdz9&31n./45tmcr*x,'(bui5apv#-t0ljk26.dt4,zsq/c+b&osu3r
ypg!ax)q0l.61#293u%zu/m(cd-k4hv+e'50r,&lpu)6b#ajk2.iwzc*gh(0r4
l,9v62okkmkzba'1/ct.i0qk4,2ehxk-psdw'*%sj&zgsybiac#e)+.3oyy934
)u/0r,hm'v2lbwgpt9z6mc(k#*v/ei3a

1117 characters  49 different  (each datum is count)
   224 2202727271932203017292427172829302220 2273030282732 327272818342027 8182418203121301831221528
   ! # $ % & ' ( ) * + , - . / 0 1 2 3 4 5 6 8 9 a b c d e f g h i j k l m n o p q r s t u v w x y z
!  . . . . . . . . . . . . . . . . . . . . . . 1 1 . . . . . . . . . . . . . . . . . . . . . . . . .
#  . . . . . . . 1 3 . 1 1 2 . . . 1 2 . . . . . 2 1 . . 3 . 1 1 . . . . 1 . . . 1 . 1 . . . . 1 . 1
$  . . . . . . . . . . . 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 . . . . .
%  . . . . 1 . . . 1 1 . . . . 1 1 . . 1 . . . 1 2 2 1 . . . 2 . . . . . 1 . . . 1 . 1 . . . 1 1 . 1
&  . . . 1 . . . . 3 . 1 . . . 1 3 2 3 1 1 . . . . . . . . . . . . 1 2 1 1 . 1 . . 1 . . 2 . . . . 2
'  . . . . . . 1 . 1 . . 2 . . . 1 1 1 . 4 1 . 2 . 2 . . 1 . . . . . . . . . 1 . . . . 1 . 3 1 4 . .
(  . . . 1 . . . . 2 1 1 . 1 . 2 . . . 1 . 1 . 1 1 2 3 1 . . . . . 1 1 1 . . . 1 . . . 1 . . 2 . . 2
)  . 1 . 1 . . . . . 2 1 . . 1 . . . . 1 . 1 . . 1 2 . . . . . . . . . . . . 1 . 3 . . . 4 . . . . .
*  . 1 . 2 1 4 . 1 . . . . . 1 . . . 2 . . . 1 . . . 1 2 . . 1 3 1 . 1 . . 1 . 2 2 . 2 . . 1 . 1 . 1
+  . . . 1 . . . . 1 . 1 . 2 . . . . . 3 . . . . 1 2 . . 2 . . . . . . . 2 . . . 2 . 1 . . . 1 1 . .
,  . 7 . . 2 1 1 1 1 . . . . . . . 1 . . 1 . 1 1 . 2 . 2 1 . 1 1 . . . . . . . 1 . . . 1 . 1 . . 1 2
-  . . . 1 . 1 1 1 . . . . . . . . . . . . . . . . . . . . . . 1 1 1 3 . . . . 2 . . 1 2 . . . . 1 1
.  . . . 1 . . 1 . 1 1 . 1 . 2 . . . 1 2 5 1 . . . . . 2 1 . . 1 4 . 1 . . . . . . . 2 1 . . . . . 1
/  . . . 1 2 . . . . . . 1 1 . 1 2 1 . 2 . . . . 2 . 5 . 1 . . . . . 1 . 2 . . . . . . 1 . . 1 . . .
0  . 1 . . . . 1 1 . . 1 1 . . . . 1 . 1 . 2 . 1 . . . 1 1 . . . . 1 . 2 1 . . 1 2 7 . . 1 . . . . .
1  . 2 1 . . 1 . 1 . . . . . 2 . . . . . . . . 1 . . . . . . . 2 . . 3 . . 1 . 1 . . 2 . . . . . . .
2  . 2 . 1 . 1 . . . . . . 1 . . . . . . . 3 . 1 2 . . . 2 . 1 . . 1 . 4 . . 1 . . 4 . . 2 . . . . 2
3  . . . . . . . . 1 . 2 1 1 1 . 1 . . 2 . 1 . . 3 1 . . . . 1 . . 1 . 2 1 . 3 . 1 1 . . 1 . 3 . . 1
4  . 1 1 . 1 1 2 3 1 1 2 . . 1 . . . . . 2 . . . . . 1 1 2 1 . 1 . . 2 1 . 2 . 1 . . 2 . . . . . . .
5  . . . . 1 . 1 1 . . . . . . 2 . . . . . . . 3 2 1 . . 2 . . . . . . . 2 . . 1 . 2 . 2 1 . . 1 . .
6  . . . . . . . . . . . . 2 . . 1 1 . 1 . . . . . 3 1 . 1 . 2 . 1 . . . 1 . . . . . . . 1 . 5 . . .
8  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 . . . . .
9  . . . 1 4 1 3 . . 1 . . . . . . 1 3 . . . . . . . 1 1 . . . 1 4 . . . . . . . . . 2 . . 2 . . . 2
a  . . . . 2 2 . 1 2 . . . 5 1 . . . 2 . . . . . . . 1 . 2 . 1 . . 1 . . . . . 2 . . 2 1 . . 1 3 . .
b  . 1 . . 4 . 2 . 1 . . . . 1 . . . . . . . . 1 2 . . 1 1 2 . 1 3 . 3 . . . . . . . . 1 1 1 1 . 2 1
c  . 1 . . 1 . 1 . 2 1 . . . . 1 1 . 1 2 . 1 . . . . . 2 . . 2 . . . . 2 2 . 1 . . 3 1 1 . . 1 1 . .
d  . . . 1 2 . . 1 . 1 1 1 . . 1 1 1 . . . 1 . 1 . 1 1 . 1 . 1 . . 1 1 . 1 . 1 . . . 1 2 1 . 2 . . 1
e  . 1 . 1 1 4 2 2 . 1 . . . 2 . . 1 1 . . . . . . . 1 1 . . . 2 3 . . . . 2 . 2 . . 1 1 . 1 . 1 . 1
f  . . . . . . . . . . . . . . . . 1 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
g  1 . . . 2 1 1 1 . 1 1 . 1 . 3 1 1 1 . . . . . . . 1 4 . . . 2 . . 1 . . 2 . 1 . . 1 . . . . . . .
h  . . . 1 . . 4 . . . . . . . 2 . 3 1 . 1 . . . 1 1 3 . 1 . . . . . . . 1 . . . 1 . . . . 3 . 4 . .
i  . . . . 1 . . . 1 . 1 . 2 . 1 . 1 3 . 5 . . . 1 1 1 1 . . . 1 . . . . . . 1 . 1 . . . . 1 1 2 1 1
j  1 2 . . 1 1 . . . . . . . 1 . . . . . . . . 1 . . . . 1 . 1 2 2 . 3 . . . . 1 . . . . 1 . . . . .
k  . 1 . 1 . . . . 2 . . 1 . 4 1 1 3 . 3 . 2 . 1 . . . . 2 . 1 . . 2 1 . 1 . 1 . . . 1 . 1 . 2 . . 2
l  . . . . . . . . . . 1 1 2 . 1 . . . 1 . 1 . 1 2 1 . . 1 . 2 . . 2 . . . . . 3 1 . . . . . . . . .
m  . . . 1 1 2 3 . . 2 1 1 . . 2 . 1 . . 1 . . . . . 2 1 1 . . 1 1 1 1 . . . . . . . 1 . . . . 1 . 2
n  . . . . . . . . . . 3 1 1 . . . . . . . . . . 1 . . . . . . . . . . . . . 1 . . . . . . . 1 . . .
o  . . . . . 1 . . . 1 . . . . 1 1 . . . . . . . . . . . . . . 1 . . 5 . 1 . . . . . 1 . 4 . 1 . 1 .
p  . . . 1 . 1 1 . . 1 2 . 1 . . . . 1 . . . . 1 2 . 1 1 . . 1 . 1 . . . 1 . 3 . . . 1 1 1 1 1 . . .
q  . . . . . . . 2 . . . 1 . 1 2 . 1 . 1 . . . . . . . 1 2 . . . . . 1 . . . . . 1 . 1 2 . . . . 2 .
r  . . . . . . . . 2 . 3 . 4 . . . . 1 3 . . . 1 1 2 . . . . 1 . . . . . . . . . . . . . . . 1 . 1 .
s  . . . 1 . . . . 2 . 2 . . 1 . 1 . 1 2 . . . 3 1 . . 1 1 . 1 . . 1 . . 3 . 1 . 1 . 1 . 1 . 3 . 1 2
t  . . . . . . . . 3 . . . 2 . 1 1 . . 2 . 1 . 3 . 1 . . . . 2 . . . . 2 1 . . . . 1 . . . . 1 . . .
u  . . . 2 . 1 . 1 . 2 . . . 2 2 . 2 2 1 1 . . . . 1 . 1 1 . . . 2 . . . 1 . . 1 . . 1 . . 3 . . 3 .
v  . 1 . . . 1 1 . . 1 . . . 1 . . 1 . . . 2 . . . 1 . 1 . . 1 . . 1 . 1 2 . . 1 . . . . 2 . . . . .
w  . 2 . . . 3 . . . . . . . 2 . . 2 1 . 1 . . . . . 1 1 . . 1 6 3 . . . 1 . . 2 . . 2 . . 1 . 1 . 1
x  . . . . . . 1 1 . . 2 . . . 1 . 1 . . . . . . 1 . . 1 . . 1 . 1 1 3 1 . . . . . . . 3 2 . 1 . . 1
y  . . . . . . . . 1 . 1 1 . . 1 1 . . . . . . 1 . 1 1 . 1 . . . . 1 . 1 . . 1 1 . . . . . . . . 2 .
z  . . . . . . . . 1 2 2 2 1 . . . . . . . 2 . 1 1 2 2 . . . 2 . 1 1 1 2 . . 1 . 1 1 1 . 1 . . . . .

digram frequency: Pride and Prejudice (non-alphabetic characters removed) 
536406 characters     (each datum is ratio*10000; eg. 'a' ratio 777/10000, 'aa' ratio 1/10000)
   777 169 251 416 1293 224 187 635 705  16  60 403 275 703 746 153  12 602 617 870 279 107 229  16 237  17
      a   b   c   d   e   f   g   h   i   j   k   l   m   n   o   p   q   r   s   t   u   v   w   x   y   z
a     1  30  24  47   0  12  18   2  30   0  11  55  29 149   1  17   0  79  96 107  10  28   9   0  23   0
b     5   0   .   0  78   .   .   0   8   3   .  19   0   .  12   .   .   6   3   2  21   0   .   .  12   .
c    26   0   6   0  46   0   .  42  10   .   8   6   0   0  58   0   2   6   0  24   7   .   0   .  10   .
d    47  19   5   8  55   8   5  26  55   2   1   7  14  17  29   4   0   8  24  42   6   3  15   .  12   .
e    99  17  51 114  46  28  13  36  49   2   4  71  47 125  30  25   4 221  99  92   3  30  44  14  30   .
f    23   2   3   2  23  12   1  14  21   0   0   4   6   1  44   2   0  17   6  25   7   0   4   .   4   .
g    22   4   1   1  26   2   1  35  15   0   0  11   4   3  15   1   0  13   7  14   3   0   4   .   2   .
h   130   3   2   2 278   2   1   9  89   1   0   2   6   1  53   2   0   4   7  27   6   0   6   .   3   .
i    20   7  31  28  28  14  16   6   0   0   6  33  34 188  40   3   0  28  95  92   0  16   4   1   0  14
j     6   .   .   .   4   .   .   .   0   .   .   .   .   .   3   .   .   .   .   .   3   .   .   .   .   .
k     3   0   0   0  20   1   0   5  11   0   0   1   0   9   2   0   0   0   3   2   0   0   2   .   1   .
l    32   4   3  32  68  14   1   4  62   0   5  59   4   3  28   2   0   1   7  13   6   2   5   .  47   .
m    43   6   1   1  60   2   1   4  32   0   0   1   7   2  26  14   0  21  11   9  14   0   4   .  16   .
n    33   6  35 107  81   9  91  15  28   2   7  11   8  16  74   3   2   2  39  96   5   6  12   1  14   0
o    10  17   9  15   6  77   5  14  11   1   8  24  52 116  28  14   0  75  30  62 117  10  39   0   4   0
p    19   0   0   0  32   0   0   2   8   0   .  17   0   0  19  13   .  25   4   7   3   0   1   .   2   .
q     .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   .   0  12   .   .   .   .   .
r    46  12  22  26 142  13   6  16  48   1   3  13  18  14  45   7   0  15  52  47   7   5  15   .  27   .
s    54  15  15   7  78  11   5  66  56   1   2   8  13  11  50  20   1   5  53  90  30   3  19   .   4   .
t    54  13   9   7  87   7   2 279  84   1   2  20  14   6 114   6   1  19  27  54  17   1  25   .  19   1
u    12   5  21   6   8   1  16   2   8   0   1  33   7  27   1   9   0  49  33  36   0   0   3   0   0   0
v     7   .   .   .  80   .   .   .  16   .   .   .   .   .   4   .   .   0   .   .   0   .   .   .   0   .
w    53   1   1   1  34   1   0  46  49   0   0   2   2  10  20   0   0   2   3   3   0   0   2   .   0   .
x     1   0   3   .   1   0   .   0   1   .   .   .   0   .   0   5   0   .   .   3   0   .   0   .   0   .
y    20   8   9  11  11   7   3  11  14   1   1   5   9   4  51   5   0   5  21  22   2   1  15   .   2   .
z    12   .   .   .   1   .   .   .   0   .   .   0   .   .   .   .   .   .   .   .   .   .   1   .   2   2

    black chamber day: 1860

     
    FOR NEXT TIME: make column width divisible by keylength

KRWAOIBCZMBPKSMVMWFEJMNMFIVMXKOTZIDIZPSZOVDLQKYVPIJU
CBREALOVDILGYNDHWEYUKNTMRQXDLPOUYNSTSAKSAKYVSCKUSTOG
WZWIXYKCXQFEJASBIOXPOQNEDJOZQSSGCAREAAVQCAVMVOSOUWXL
YWANOWPFDWBMXTAVOJESAVOACMSVPZKNUMCKYDWTQQYCGVNWKCUW
BLSNYBYVYTWAGZSTLMXQXTZMWIBGAVCWPATWYSLYSNBQONVWPTOO
FIBLYDSDSVMISADPOAJBSADWGZUMNOFBRMWAKBOZZIWKOBREKKRW
YLKISLSNSADIDEEMXBWOFLKGDHWLSAMONMBGLYSPOQNEDJOZQUFQ
FMBSABITSBJIBGWAFCCKBIHBOFZEJBKXZESZCBYCGVPQBMOPKBRA
KTYVQBWMXAESHMMBODABSAKLKWKVKNKEOZDHSBRICBWMXQXPDISV
FIWEPWBCWVDCBIWADPOMGVKTSSSQCSXOOVKAVAYQYKYNVISVSTST
SIXDWTQQYCGVNWGAKNSZCTFIWMNAKBRMVICMXMCSAVDPOPSQXBSN
YJIQDADQKVGRABOZQIGZQQYVSAKZSIFERWKLKWNIDEVBRMGOJSKB
LELEOMXAFLDPOUFQFMBSABIAKIV

    black chamber day

     
    ghrjdtip gszjwc chahyc yzi zy kwfzdtisx ghrdhrp eji zy vhp ghrdhrp

    black chamber day: 1918

     
    __  ___  ._.  ...  .  _._.  ___  _..  .  ...  

_  ..  ._..  ._..  .._  ...  .  _..  _  ___ 

_..  ._  _.__  ..__.. 

..._  .._.  _.._  .._.  __.  _..  __.  ..._  _..  ._  

..._  .._.  _..  .._.  ._  _.._  _.._  ..._  _.._  ._  

..._  ..._  ._  ..._  __.  _..  .._.  ..._  __.  ..._  

_..  ..._  _.._  __.  __.  ..._  _..  __.  .._.  _..  

..._  _..  _..  __.  .._.  _.._

    black chamber day: 1942

     
    u  n  i  v  e  r  s  i  t  a  t

F  U  U  X  U  S  A  J  T  S  I  E  N  C  V  R  T  M  P  T  N  A  R

    black chamber day: evolution of one-time-pad

     
    xli izspyxmsr sj xli sri-xmqi-teh

Ycpgvcvcmc lkdpi pfi Rcnc-gjpkc em pfi 4pf aimpjkv co. 
Ep emawjoig c oigaketpedm dh c gjxgpepjpedm aetfik.

.d-mryli-mk6iy8odbva+%7iv7mbv#o7-yrimh#-h.ola%
b18.1y7-8y7hik7'm6og7o1-9aymro1-by71-7k1hi'+a7iyl/-
+bi98a96+ry-logo6j8rik7l1i6/ysb-kmymrsh1-khsshi
k7'mloy6/-+ry-loyh-m6sh1ykhsshi+ai98b9r+l-y6oaiv1hhi

dydmeiccyhmyutwmgqmwgpxphvfcewgowprvgcwtq
jalprfcmivgenmrfgcwcpgpeugnjftmmprqlepogw
yzvfjgykvfkdkwcudifmvsitqqmwgpxphvfcelqkq
alqlkngknjpvuytpwwqeptvgdwivmnpxvctaekphc
issgygayplpaqkd

bdpoajhniyzqmurouuciknlztko
    data for 3rd cipher
    data for 4th cipher 
    196 characters  27 different    (each datum is count)
   2   3  16   3   8   6   7   2  13   1   8  11   7  16
     2   7   3  10  12   5   7   2  15   8  10   8   4
   # % ' + - . / 1 6 7 8 9 a b d g h i j k l m o r s v y
#  . . . . 1 . . . . . . . . . . . . . . . . . 1 . . . .
%  . . . . . . . . . 1 . . . 1 . . . . . . . . . . . . .
'  . . . 1 . . . . . . . . . . . . . . . . . 2 . . . . .
+  . 1 . . . . . . . . . . 2 1 . . . . . . 1 . . 2 . . .
-  . . . 2 . . . . . 1 1 1 . 1 . . 1 . . 2 2 3 . . . . 2
.  . . . . . . . 1 . . . . . . 1 . . . . . . . 1 . . . .
/  . . . . 2 . . . . . . . . . . . . . . . . . . . . . 1
1  . . . . 4 . . . . . 1 . . . . . 2 1 . . . . . . . . 2
6  . . . 1 . . 2 . . . . . . . . . . 1 1 . . . 2 . 1 . .
7  . . 2 . 2 . . 1 . . . . . . . . 1 2 . 1 1 1 1 . . . .
8  . . . . . 1 . . . . . . 1 1 . . . . . . . . 1 1 . . 1
9  . . . . . . . . 1 . 2 . 1 . . . . . . . . . . 1 . . .
a  . 1 . 1 . . . . . 1 . 1 . . . . . 2 . . . . . . . . 1
b  . . . . 1 . . 1 . . . 1 . . . . . 1 . . . . . . . 2 1
d  . . . . 1 . . . . . . . . 1 . . . . . . . . . . . . .
g  . . . . . . . . . 1 . . . . . . . . . . . . 1 . . . .
h  1 . . . 1 1 . 2 . . . . . . . . 1 5 . . . . . . 2 . .
i  . . 1 1 1 . . . 1 . . 2 . . . . . . . 3 . 1 . . . 2 2
j  . . . . . . . . . . 1 . . . . . . . . . . . . . . . .
k  . . . . . . . 1 1 3 . . . . . . 2 . . . . 1 . . . . .
l  . . . . 1 . 1 1 . . . . 1 . . . . 1 . . . . 3 . . . .
m  . . . . . . . . 2 . . . . 1 . . 1 . . 1 1 . . 3 . . 1
o  . . . . . . . 2 1 1 . . 1 . 1 2 . . . . 1 . . . . . 2
r  . . . 1 . . . . . . . . . . . . . 2 . . . . 1 . 1 . 3
s  . . . . . . . . . . . . . 1 . . 4 . . . . . . . 2 . .
v  1 . . . . . . 1 . 1 . . 1 . . . . . . . . . . . . . .
y  . . . . 2 . . . 2 3 1 . . . . . 1 . . 1 2 2 . 1 1 . .

    length 4 substring frequencies
 a  b  c  d  e  f  g  h  i  j  k  l  m  n  o  p  q  r  s  t  u  v  w  x  y  z 
 0  0  3  1  4  3  4  1  2  2  2  2  3  2  0  2  3  0  0  1  1  1  3  1  4  0 45 0.0385
 0  0  2  1  1  2  3  1  3  1  3  1  1  1  0  8  3  1  1  4  2  2  3  0  1  0 45 0.0524
 3  0  2  3  2  2  5  2  0  1  2  1  3  0  0  3  2  2  1  1  0  5  2  2  1  0 45 0.0405
 2  0  4  1  1  1  3  0  1  0  1  2  4  2  2  4  2  1  1  1  1  3  4  0  2  1 44 0.0372
0.0422
length 5 substring frequencies
 a  b  c  d  e  f  g  h  i  j  k  l  m  n  o  p  q  r  s  t  u  v  w  x  y  z 
 2  0  1  1  0  2  4  0  1  0  2  0  2  0  0  0  4  2  1  2  2  8  2  0  0  0 36 0.0741
 0  0  3  0  0  5  5  0  0  2  1  2  3  1  1  4  3  0  1  0  0  0  1  0  4  0 36 0.0664
 1  0  5  2  3  0  4  1  0  1  3  0  1  2  0  1  3  0  0  2  2  1  1  2  1  0 36 0.0463
 2  0  2  3  2  0  0  0  0  1  0  2  4  2  0 10  0  0  1  1  0  0  2  0  3  1 36 0.0973
 0  0  0  0  3  1  2  3  5  0  2  2  1  0  1  2  0  2  0  2  0  2  6  1  0  0 35 0.0621
0.0693
length 6 substring frequencies
 a  b  c  d  e  f  g  h  i  j  k  l  m  n  o  p  q  r  s  t  u  v  w  x  y  z 
 1  0  4  1  0  0  3  3  0  1  0  1  5  0  0  3  1  0  0  1  1  4  0  0  1  0 30 0.069
 1  0  3  0  0  2  1  0  1  0  2  1  1  1  2  3  0  1  1  2  1  3  3  0  1  0 30 0.0356
 2  0  0  2  0  3  5  0  2  2  1  0  0  2  0  1  2  1  0  0  0  2  4  0  1  0 30 0.0578
 1  0  2  2  1  1  4  1  1  0  1  0  2  0  0  5  2  1  1  2  1  0  1  0  1  0 30 0.0467
 0  0  1  1  6  2  1  0  0  0  3  2  1  0  0  1  2  1  1  1  0  0  1  3  3  0 30 0.0601
 0  0  1  0  1  0  1  0  2  1  1  2  2  2  0  4  3  0  0  1  1  2  3  0  1  1 29 0.0405
0.0516
gcw 21
qmwgpxphvfce 90