26197 26188 26182 26187 26192 26194 26193 26183 26187 26180 26198 26185 26180 26191 26191 26184 26193 26194 26100 26197 26185 26194 26197 26182 26184 26198 26187 26180 26101 26184 26184 26193 26199 26184 26197 26184 26183 26199 26187 26184 26182 26188 26199 26104 26197 26184 26198 26188 26198 26199 26180 26193 26182 26184 26188 26198 26184 26193 26183 26184 26183 26188 26193 26185 26194 26197 26192 26199 26187 26184 26195 26197 26184 26198 26188 26183 26184 26193 26199

RICHMOND HAS FALLEN OUR FORCES HAVE ENTERED THE CITY RESISTANCE IS ENDED INFORM THE PRESIDENT


37 82 83 84 41 13 18 20 67 32 72 75 15 81 28 22 41 44 65 83 25 66 20 12 60 64 26 83 17 44 88 63 37 66 72 75 37 28 63 77 60 20 56 66 41 28 67 83 25 63 72 22 75 28 44 34 20 63 56 84 82 41 37 83 34 66 28 25 32 71 67 20 63 37 18 59 16 28 44 72 22 66

THE CIPHER DISK WAS INVENTED BY LEON BATTISTA ALBERTI A RENAISSANCE ARCHITECT AND GREAT HUMANIST


LGRL CLBQL RPQ RQ BLRPLO OSICBKJR QOLJPYORPPK IRGGSH BCUCGR CJBCMCQ MRO QKQLH OKHLJLH

ALEA IACTA EST ET CAESAR RUBICONE TRANSGRESSO BELLUM CIVILE INCIPIT PER TOTAM ROMANAM


DEAATSEIRIWGNETSNAILCDSSMLHAEHSMSI

DAS GEHEIMNIS ALLER MACHT IST DAS WISSEN


JCQPDEJSVGCRKSSUWSOXSYNITWRJ


KHYTOBYIORZAIPTA


THE VIGENERE CIPHER USES A REPEATING KEYWORD GRONSFELD USES A DIGIT SEQUENCE AS THE REPEATING KEY THE ARCHITECTURE SHOULD MAKE MISUSE HARDER

Morse code: dots and dashes; word-separated by / symbol.


NROBXJDYDKCJNMUKVB


CJZCCZPCMNYCLGTGLHIYFZCPIUPWNOYRGZFPPYZHZDUBCCSSTZZVHVRVNKQTIKPVWTXAGSRLRZWMKJP

GOOD EDUCATIONAL TOOLS EXPLAIN THEIR LIMITS HISTORICAL CIPHERS ARE TEACHERS NOT PROTECTION

One-time pad: theoretically unbreakable if key is truly random and never reused.


WPEWNVNOLRSKQIDQPWNNCXMMVSTAQWMOSOMMVSCUMNRLSLXUFKCUXMPQSKHHPYIMKQBPDZJD

QUOTH THE RAVEN NEVERMORE THE BIRD SAT ON THE BUST OF PALLAS JUST ABOVE MY CHAMBER DOOR


WELTFSFKLKLJATELTWEFNEWANLIILRMSAOYLKYMTEARKLJAWMUIDSJAIILSSWAAT

WHAT IS IN A NAME THAT WHICH WE CALL A ROSE BY ANY OTHER NAME WOULD SMELL AS SWEET


IKNOWNOTWHATCOURSEOTHERQMAYTAKEBUTASFORMEGIVEMELIBERTYMRGIVEMEDEATH

I KNOW NOT WHAT COURSE OTHERS MAY TAKE BUT AS FOR ME GIVE ME LIBERTY OR GIVE ME DEATH


track heads eight known after scout inner stage knife incur eight extra array moved input needs again takes issue often night flank inner needs draft

THE KASISKI EXAMINATION FINDS REPEATED TRIGRAMS IN CIPHERTEXT AN AFFINE CIPHER APPLIES A LINEAR FUNCTION TO EACH LETTER ATBASH ENCODES BY REVERSING THE ALPHABET

Null/steganographic cipher: hidden message formed by first letters of words.


HFKKOB ORMVH SZEV YVVM XFG IZGRLMH ULI GSIVV WZBH LMOB ZDZRG IVHFKKOB LI YIVZP GSILFTS ORMVH

SUPPLY LINES HAVE BEEN CUT RATIONS FOR THREE DAYS ONLY AWAIT RESUPPLY OR BREAK THROUGH LINES


39 75 16 63 33 87 41 77 71 49 20 42 46 29 64 57 88 63 25 39 44 87 58 27 71 61 63 38 57 75 59 11 21 64 69 46 36 65 10 28 77 11 33 42 27 39 34 71 44 23 75 20 39 77 42 28 11 38 87 21 27 29 65 33 75 59 28 46 71 42 67

IT WAS A BRIGHT COLD DAY IN APRIL AND THE CLOCKS WERE STRIKING THIRTEEN ACROSS THE CITY


173 177 110 179 171 100 108 138 167 180 117 108 128 114 182 160 147 114


HIQNA HU LUNFLTGPXHE NWKNATNUXN PI QYN TUNIITXTNUXR PI QYN VLCVTVQTUD INSNAHE DPGNAUZNUQ RPL HAN XHEENS LKPU QP SNETCNAHQN PU H UNB XPUVQTQLQTPU IPA QYN LUTQNS VQHQNV PI HZNATXH

AFTER AN UNEQUIVOCAL EXPERIENCE OF THE INEFFICIENCY OF THE SUBSISTING FEDERAL GOVERNMENT YOU ARE CALLED UPON TO DELIBERATE ON A NEW CONSTITUTION FOR THE UNITED STATES OF AMERICA


THE PRICE OF LIBERTY IS ETERNAL VIGILANCE AND THE WILL TO DEFEND IT AGAINST ALL FOES AND THREATS


DYOJKXGQZGQTRPWKWEYAWWGBBNPNKOZTAZXZTZDZSNIJVXNTNBENGAPALLJGJURWLFPHNHYYOXBGLVACKQNFUXDFWVGCMCCPCZDDZFJPEBGANWQWHUKYOSPDZACBBILRSEYNRGBMQYTHWBWFPOWSEIVYURJMOJXRBHDSXHM

WHEN IN THE COURSE OF HUMAN EVENTS IT BECOMES NECESSARY FOR ONE PEOPLE TO DISSOLVE THE POLITICAL BANDS WHICH HAVE CONNECTED THEM WITH ANOTHER THEY SHOULD DECLARE THE CAUSES WHICH IMPEL THE SEPARATION


CRYPTOGRAPHY REWARDS PATIENCE AND CAREFUL THINKING KERCKHOFFS PRINCIPLE SAYS THE SYSTEM MUST BE SECURE EVEN IF ENEMY KNOWS ALGORITHM THE ENIGMA MACHINE USED ROTORS TO CREATE A POLYALPHABETIC CIPHER


TMUFTGQZIWXNPB


OSLWMFKTFQAXALREANCUGRRRBLFQXZNWRWKJOGSEXBLZCSDTCOLXFSKNYXVEEXHIRECVMINGIFFHOSIUFNYITAEAKSEDMRCZQOMRIARBKCPBYELVUXUZLQVDYJBRVCXFZGNDHXDNASLXFXZAFXAVSUGULBWVKGTCIEON

IN THE SEVENTEENTH CENTURY ISAAC NEWTON SYNTHESIZED THE WORK OF COPERNICUS GALILEO AND KEPLER INTO A UNIFIED THEORY OF GRAVITATION THAT EXPLAINED BOTH THE FALL OF APPLES AND THE ORBITS OF PLANETS


19.5.4 11.6.4 7.1.5 7.3.9 15.1.9 6.3.5 11.6.7 10.3.7 11.5.5 17.6.10 2.6.9 19.1.5 12.2.3 9.3.10 8.3.6 14.3.7 19.2.4 12.3.5 11.5.4 20.3.7 8.5.4 19.2.2 14.6.9 18.5.5 9.4.5 3.2.8 9.6.3 20.4.2 7.1.2 1.6.7 9.3.3 14.6.5 1.2.5 11.5.9 3.2.5 8.2.9 14.5.1 11.1.7 18.2.4 3.4.1 8.5.7 13.3.6 14.1.6 12.1.9 5.6.10 6.6.9 11.2.1 14.3.6 18.5.8 20.6.6 18.1.1 16.6.10 1.3.1 13.1.10 15.1.3 14.2.7 17.5.3 6.1.3 8.1.6 9.5.2 17.2.3 20.4.10 11.5.2 20.2.9 8.2.10 4.3.2 11.2.10 8.4.8 18.1.1 5.6.6 20.4.9 4.3.1 11.4.9 15.6.8 9.3.7 5.6.8 19.3.10 17.4.5 6.3.2 3.1.2 12.4.4 6.2.1 18.5.5 15.5.7 19.4.3 10.5.5 1.6.2 9.3.4 19.3.9 19.6.2 3.4.2 20.5.4 13.2.1 2.3.1 13.2.5 16.4.2 17.6.7 19.2.9 15.5.2 6.5.8 13.2.10 19.3.3 11.2.5 10.3.5 17.2.1 10.5.9 3.3.5 5.2.1 1.6.4 10.4.4 1.5.10 5.2.10 1.5.7 1.2.1 10.4.7 10.4.5 10.4.10 10.6.7 6.2.4 1.5.9 6.3.5 20.1.9 12.1.7 16.2.7 2.3.9 7.4.9 18.5.9 18.3.7 19.2.2 8.1.9 17.6.5 5.1.10 12.3.1 19.6.10 20.6.9 12.6.7 20.1.7 1.1.3 17.4.1 15.2.8 9.1.2 9.3.6 4.6.4 13.2.1 2.5.2 17.1.5 16.6.5 15.2.2 12.1.6 7.2.7 8.5.6 2.5.2 3.1.3 8.3.5 11.5.5 10.6.10 14.5.8 10.5.7 14.3.7 13.2.7 18.6.3 8.5.1

EVERY SYSTEM NEEDS AN HONEST THREAT MODEL PUBLIC INFRASTRUCTURE DESERVES CAREFUL DESIGN DOUBLE TRANSPOSITION APPLIES COLUMNAR ENCRYPTION TWICE DO NOT CONFUSE OBFUSCATION WITH ENCRYPTION

Arnold-André book cipher: coordinates (page.section.word) referencing a shared text.


QYMCCEADGTLNQGPNNHEVQDRZTCLUUFPGWQBDOAYLITQMZJKJAJUNYJWENSQDSASGTLBTRLCQOFSWAZTQOV

ZERO KNOWLEDGE PROOFS ALLOW ONE PARTY TO PROVE KNOWLEDGE WITHOUT REVEALING THE KNOWLEDGE ITSELF


DWFKPGQOWIHVEKXSIQYYHWIQYYHWIQFPXEHILIJCLFOIMELPFXHVFCNOTDOYTDUMTWUVXB

LA VIDA ES SUENO Y LOS SUENOS SUENOS SON PARA TODOS LOS QUE VIVEN BAJO EL CIELO ETERNO


IT WAS THE BEST OF TIMES IT WAS THE WORST OF TIMES


IMQGFMSNPDNAQYZXSDCYLKGVS


VPQXLPXLDUTVZD


AWV FGKI AWYGN HV WTEV AF OVTU YB OVTU YABVKO

THE ONLY THING WE HAVE TO FEAR IS FEAR ITSELF


TBEMLJYTBDLAWEBCVETMRECQDSRECQDTSEJR


RO GVNKL V GRIZMML


TIGHWJXYRUBREDHFBODCLMEGCNMZYSWTGQCHFPDGHERELVLVBWJSLLSLAOEDOJ

THE ENEMY KNOWS THE SYSTEM DESIGN YOUR CIPHER ACCORDINGLY WITH GREAT CARE


EQXTWKCKKPADHCMFTGMHWGEDLXTNELRJFVPOLAYFQTGSQHQWXBLRCNEEKTWVJPRJUDLNKFWRJIEBDKSDNSJ

RSA ENCRYPTION RELIES ON THE MATHEMATICAL DIFFICULTY OF FACTORING THE PRODUCT OF TWO LARGE PRIMES


HBIIPRLAJPVVYJIXHMQJUVPBIJIHBXYZJBHMOPBIRCJPQAJUYBLAJDMJPLJULUJPCHMBJYBZPUYHB

ON D DAY THE ALLIED FORCES LANDED ON FIVE NORMANDY BEACHES IN THE GREATEST SEABORNE INVASION


GUR ZRFFNTR JNF UVQQRA OHG ABG FRPHER QVTENCU NAQ GEVTENCU SERDHRAPVRF RKCBFR FVZCYR PVCUREF ORNHSBEG VF GUR ERPVCEBPNY BS IVTRARER NAQ QRPELCGF VGFRYS GUR QRGRPGVIR FGHQVRF CNGGREAF ORSBER ZNXVAT PYNVZF

THE MESSAGE WAS HIDDEN BUT NOT SECURE DIGRAPH AND TRIGRAPH FREQUENCIES EXPOSE SIMPLE CIPHERS BEAUFORT IS THE RECIPROCAL OF VIGENERE AND DECRYPTS ITSELF THE DETECTIVE STUDIES PATTERNS BEFORE MAKING CLAIMS

ROT-13 is Caesar with shift 13 — it is its own inverse.


YQDWDUJULVWMNAHRXQUFNROLOFRNJGFFARIGIUZYQHAQCBLYISLKUFYAAMMPLKWYBXZTBJIEHTYAKICETSBVIRJAFFOUXPQONLMHWNDQAUSNFJRZCQUXMLCOJXZHNPDPQKLAHXDL

ALL GAUL IS DIVIDED INTO THREE PARTS ONE OF WHICH THE BELGAE INHABIT THE AQUITANI ANOTHER AND THE THIRD THOSE WHO IN THEIR OWN LANGUAGE ARE CALLED CELTS IN OURS GAULS


UFKIRAYRVXRDXPRIJVJGPYTFD


ULBNBUTUUKDGBY


KWCZIOMQVLIZSVMAA


14.4.3 16.2.9 14.5.5 13.6.8 11.1.4 2.3.3 18.2.7 3.3.9 8.4.10 3.4.4 2.5.1 9.4.8 12.5.9 19.2.2 19.3.8 14.2.8 16.6.6 10.1.7 14.3.10 12.1.5 18.3.9 7.6.6 1.3.9 17.5.8 16.6.10 6.4.3 9.2.4 13.2.4 3.5.5 19.1.6 12.5.10 1.1.1 18.3.2 17.6.8 2.5.7 9.3.5 13.5.1 19.3.1 18.6.5 5.4.2 20.3.1 4.6.7 13.6.9 5.4.7 14.1.7 1.4.3 9.6.1 15.5.5 6.3.3 13.6.2 11.2.5 12.3.5 7.6.6 18.4.7 13.2.9 1.4.6 2.2.1 2.5.10 19.2.2 2.5.2 20.4.2 7.6.9 4.1.5 9.5.6 3.4.1 2.5.8 5.2.5 14.4.5 6.6.5 2.5.3 13.6.3 18.3.10 13.5.5 10.6.1 18.5.6 9.5.6 1.6.10 13.1.4 3.3.2 15.1.2 6.5.7 1.6.5 8.3.7 14.5.3 13.2.6 15.3.2 17.1.4 2.4.10 17.3.9 12.5.2 2.6.8 11.5.2 8.1.2 19.6.5 1.5.3 4.5.1 12.6.6 12.6.9 16.3.4 20.3.1 7.3.2 10.4.4 8.3.8 10.1.4 8.2.10 5.1.4 19.4.1 19.1.3 3.4.8 20.3.4 4.4.5 15.4.2 14.6.7 5.2.6 3.6.8 5.1.3 8.2.7 11.3.10 2.2.4 17.2.3 17.1.10 20.6.6 19.5.2 10.6.6 11.2.6 18.2.8 8.4.3 6.2.7 1.4.2 10.5.6 5.1.9 19.3.5 18.2.5 9.5.7 14.6.3 7.4.2 19.2.9 9.5.2 13.5.10 1.1.1 7.3.7 11.4.8 7.1.4 3.1.8 20.5.10 1.1.4 14.3.8 3.2.9 15.5.5 17.1.6 8.6.4 7.6.5

FRIEDMAN ESTIMATED KEY LENGTH FROM STATISTICS THE TRITHEMIUS CIPHER ADVANCES THE ALPHABET BY ONE POSITION EACH LETTER HILL CIPHER USES LINEAR ALGEBRA TO ENCRYPT BLOCKS OF LETTERS


03 08 01 18 20 60 21 14 11 14 15 23 14


FUIYFIIXBBUXVYXK


UHZVAG BE UHZNA VAGRYYVTRAPR TNGUREVAT ERYVRF BA CREFBANY PBAGNPG NAQ UHZNA FBHEPRF VA GUR SVRYQ

HUMINT OR HUMAN INTELLIGENCE GATHERING RELIES ON PERSONAL CONTACT AND HUMAN SOURCES IN THE FIELD


NLSXNRWJOEFLCOSPKAENQYVXRQMOPNXZVZENFOLAJNOOKJGIBRISZHYHIHTRPXISVLSEMPEPLHKZAU

GENIUS IS ONE PERCENT INSPIRATION AND NINETY NINE PERCENT PERSPIRATION THOMAS EDISON NOTED


44 23 15 21 42 24 15 14 32 11 33 44 15 43 44 45 43 15 43 44 23 15 24 33 14 15 53 34 21 13 34 24 33 13 24 14 15 33 13 15 44 34 15 43 44 24 32 11 44 15 25 15 54 31 15 33 22 44 23 22 34 34 14 15 14 45 13 11 44 24 34 33 11 31 44 34 34 31 43 15 53 35 31 11 24 33 44 23 15 24 42 31 24 32 24 44 43 35 15 15 42 42 15 51 24 15 52 11 33 14 42 15 35 42 34 14 45 13 24 12 24 31 24 44 54 32 11 44 44 15 42 24 33 42 15 43 15 11 42 13 23

THE FRIEDMAN TEST USES THE INDEX OF COINCIDENCE TO ESTIMATE KEY LENGTH GOOD EDUCATIONAL TOOLS EXPLAIN THEIR LIMITS PEER REVIEW AND REPRODUCIBILITY MATTER IN RESEARCH

Polybius square: 5×5 grid maps letters to two-digit row-column pairs.


UJQFEOILJYZDDUDPGOXMOBXKOFRLJNVRHREZZQLGTFTECAGYBSSRZHFQYGJRTZVKALXBPRGFTKWFAQGEJ

THOSE WHO CANNOT REMEMBER THE PAST ARE CONDEMNED TO REPEAT IT AS PHILOSOPHER SANTAYANA OBSERVED


KL YVL ZIOG ZQIJJ YZ MVLYDZ YVL DYML CX YXM CIV EUQQEL EUJL UZ VCIXMLM KUQG Y ZELLB

WE ARE SUCH STUFF AS DREAMS ARE MADE ON AND OUR LITTLE LIFE IS ROUNDED WITH A SLEEP


01 23 01 09 20 13 25 19 09 07 14 01 12


TLSKBYNISEHOBERSIEFAEGECETNNOLHYTOAEGTUIIIWDKMECNTSSEETDNRDSTAESHECYASOBNAEVIPMERATNMIPTECYTHDFSHATROTOTOEENHEFLSHRDRAOTCEEOEBELDSROWSVYRYTXYFHEEAASOXPWOWRCPTRXTIMHYUAHEXOTAOSNTAVX

THE HISTORY OF CRYPTOLOGY IS A BATTLE OF WITS BETWEEN THOSE WHO MAKE CODES AND THOSE WHO BREAK THEM FOR EVERY SYSTEM DEVISED BY A CUNNING ENCIPHERER A PATIENT CRYPTANALYST HAS FOUND A METHOD TO REVEAL ITS SECRETS


THE FRIEDMAN TEST USES THE INDEX OF COINCIDENCE TO ESTIMATE KEY LENGTH TWO SQUARE CIPHER ENCRYPTS DIGRAPHS WITH TWO POLYBIUS ALPHABETS

Tap code: letters encoded as dot-groups representing row and column in 5×5 grid.


MYXQBOCC CRKVV WKUO XY VKG BOCZOMDSXQ KX OCDKLVSCRWOXD YP BOVSQSYX YB ZBYRSLSDSXQ DRO PBOO OHOBMSCO

CONGRESS SHALL MAKE NO LAW RESPECTING AN ESTABLISHMENT OF RELIGION OR PROHIBITING THE FREE EXERCISE


07 18 01 22 09 20 25 05 24 16 12 01 09 14 19 01 12 12


OKALY KCHEO LOKED YDARA LCHOR QOKAL ORORD ALAII INCHE DALSH ORYTE DYRAI INYTE DYAII INDAI INSHE EDYOK EDYOK EDYSH ALLKA IINOK ALQOT EDYYP CHOLO TOLYT EDYYK CHEOL CHORQ OTEDY OKEDY OKEDY OKEED YOROR SHALO XEDCH EDALQ OKEED YRAII NOROR QOKED YOTED YOTAI NCHED YQOKE EDYCH EOLOT EDYCH EDYDA LSHOR OKAIN YTAII NOTAI INDAR ALYPC HOLCH EDALS HORRC HEOLQ OKEDY CHEDA LCHOR OTAIN

THE KASISKI EXAMINATION FINDS REPEATED TRIGRAMS IN CIPHERTEXT BEAUFORT IS THE RECIPROCAL OF VIGENERE AND DECRYPTS ITSELF PUBLIC INFRASTRUCTURE DESERVES CAREFUL DESIGN CAESAR SHIFTED THE ALPHABET BY THREE POSITIONS

Voynich manuscript: undeciphered 15th-century script; pseudo-syllabic output.


YMJ WJLNRJSY BNQQ MTQI NYX UTXNYNTS ZSYNQ WJNSKTWHJRJSYX FWWNAJ KWTR YMJ JFXYJWS HTRRFSI UTXY MJWJ

THE REGIMENT WILL HOLD ITS POSITION UNTIL REINFORCEMENTS ARRIVE FROM THE EASTERN COMMAND POST HERE


WHCLEOLHDEFHLRELIITIELULFHTESOEIANFFNSGLNNDELHWTIIDNGSNHATWHDSGEHETSVEREWISELHWITEHLLESONETDSHNERXXSSTATSISGNHBFIEATGHNARLHHUXXRAELENTARHLAG

WE SHALL FIGHT ON THE BEACHES WE SHALL FIGHT ON THE LANDING GROUNDS WE SHALL FIGHT IN THE FIELDS AND IN THE STREETS WE SHALL FIGHT IN THE HILLS WE SHALL NEVER SURRENDER


AAAA AABA BAAA AAAA BBAA BAAB ABAA BBBA AAAA BAAA ABBA AAAB BAAA AABB AAAA ABBA BABA ABAA BAAA ABAA ABBA AABA AAAA BBAA BABB AAAA ABAB AAAB AAAB AABA AABB BAAA BABA AAAA BAAA AAAA BBAA ABAA AAAA BBAA AAAB BBAA BAAA BBBA ABAA AAAA BABB ABAB ABBA AAAB AABA AABA BBAA AAAA AABA AABB BABA AAAB BAAA ABAA AAAA AABB AAAA AAAA ABAB AABA BABA AAAB BAAA ABAA AAAB AABA AAAB BBAA ABBB AABA ABAA AAAA AAAA BBBA ABBB AABA BAAB AAAA ABAA BAAA BAAA AAAB ABAA BAAA ABBA AAAB AAAA AAAB AAAA AABA BBAA BBAB BAAA AABA BAAB AABA AAAB BABA BBAA BAAB AABB ABAA BAAA AAAA AAAB AAAB BBAB ABAA ABAA BAAB ABAA BAAA BAAB AAAA BAAB AAAB BBAA BAAA BAAA ABBA AAAA BBAA BAAB ABAB ABBA BAAB ABAA ABAA BBAB ABAA AABB AAAA ABAA BAAA AAAB BAAB AAAB BAAA AABA AABA AABA AABA AABA AAAA BAAB BBAA ABAA BAAA ABAB BAAB BABA BAAA ABAA BABA BAAB BAAB AAAB AAAA BBAA AAAB BAAB AABA BABA BBAB AABA BAAA BAAB BABA BAAA ABBA AAAA BAAB AAAA AABB AABA AABB AAAA ABAA ABAA ABAB BAAB AAAA AAAB AAAB BAAB BBAA AAAA BAAB AAAB ABAB AAAB AABA ABAB AABA AABA ABAA AAAA BABB AAAA AABA AABB BBBA ABBA ABAA ABBA AAAA BABA BBAA AABB ABAA ABAA ABBA ABAB AAAA ABAA AAAA ABBA ABBB AABA ABAA AABB ABAB BAA

ALAN TURING BROKE ENIGMA WITH CRIBS AND THE BOMBE MACHINE AN AFFINE CIPHER APPLIES A LINEAR FUNCTION TO EACH LETTER THE INDEX OF COINCIDENCE IS A USEFUL CLUE INDEX OF COINCIDENCE MEASURES LETTER FREQUENCY DISTRIBUTION

Bacon's biliteral cipher: each letter encoded as 5-bit A/B string.


OJOB DMLIBQ OBP QKLPKB EYJGZSOB XMIJD DZY XKSXY DK ODDOGA DZY QYLSOB YBIQSO GITZYL SOGZIBY

ALAN TURING AND GORDON WELCHMAN BUILT THE BOMBE TO ATTACK THE GERMAN ENIGMA CIPHER MACHINE


FAGAAAAAGGAAFFGAAFGAGDGFGAFAFXFXGDGXDXXAFXDGXGAGDXFAGGFGAGAFAAADDFGGADGAGADFDXGGFFXGDAGGXAGDDDDDGXXFXAGDGXADDXXDFXGGGXAAFGGAFGFDAFDAGFXADFDDAFAFDAAF

GALILEO POINTED HIS TELESCOPE AT THE HEAVENS AND CONFIRMED THAT THE EARTH ORBITS THE SUN


0856 0012 1599 0012 0729 1503 0856 0538 1421 1346 0538 0856 1024 0918 1346 0538 1421 0538 0918 0856 0918 0347 0347 1421 0472 0285 0156 0918 0012 1346 1421 0012 1672 0012 0538 1421 0538 0856 0408 1346 0538 0408 0856 0012 0729 1421 0918 0156 0918 0792 0792 0285 0856 0156 0285 1346 0472 0918 1255 0285 0074 0918 0792 0074 0012 1255 0219 0792 0285 0856 1421 0012 1421 0219 0012 1672 0856

NAVAL UNITS IN POSITION OFF THE COAST AWAITING SIGNAL TO COMMENCE SHORE BOMBARDMENT AT DAWN


HZFDNRJWKVXTZEOYYGJPG


TBE NQCYEQ MR C QDABTEMUS NEQSML DS NMWEQRUJ CLH ERREPTDVE DL QECPBDLA TBE VEQY TBQMLE MR AMH

THE PRAYER OF A RIGHTEOUS PERSON IS POWERFUL AND EFFECTIVE IN REACHING THE VERY THRONE OF GOD


FQFPOSQDTOALOUPQLETDTOTRTRFCSQTRQLQDTBOTSQQSPHOTJSFKFKBETALOTUPQDSQAOLJQDTPTDLKLOTRRTSRWTQSHTFKCOTSPTRRTVLQFLKQLQDSQCSUPTALOWDFCDQDTYBSVTQDTISPQAUIIJTSPUOT

IT IS RATHER FOR US TO BE HERE DEDICATED TO THE GREAT TASK REMAINING BEFORE US THAT FROM THESE HONORED DEAD WE TAKE INCREASED DEVOTION TO THAT CAUSE FOR WHICH THEY GAVE THE LAST FULL MEASURE


TEDECIRERIDSSBEGHU


IYAUAPIBQJEYJYOMGQAHSYITOPIYYWPBYGJEEYIOTOOYJHXMYIJMKJYKJPYFOOBNYSFJKYAPPBFJFTEBNITWBAUOTAAEJEYSEYIIPNYPUGYATAPBAPJIAPMYAOXYNFQJFEYNPYMTTEYAOYOQEBAUKGBAAPFYKYOYPTMTIJB

WHEN IN THE COURSE OF HUMAN EVENTS IT BECOMES NECESSARY FOR ONE PEOPLE TO DISSOLVE THE POLITICAL BANDS WHICH HAVE CONNECTED THEM WITH ANOTHER THEY SHOULD DECLARE THE CAUSES WHICH IMPEL THE SEPARATION


ISEATAAKXDCJJAZ


FVAAAAFXAXGFXDFDFAGFAVGGGAADFGVAGDGAFFDAFA


AINOSBOSWXIRTOXXNM


822 862 838 800 840 999 853 813 802 810 800 803 834 813 999 842 861 859 846 861 858 999 855 823 843 860 834 811 999 856 821 843 867 999 800 833 835 999 853 813 802 854 843 839 824 841 820 999 856 858 814 847 854 999 858 823 812 999 843 840 814 999 858 826 837 814 999 846 801 811 999 825 856 999 857 821 814 843 853 813 859 824 806 802 833 833 873 999 860 840 803 852 814 801 831 801 803 833 814 999 826 816 999 860 856 814 809 999 806 842 853 852 814 807 858 833 872 999 800 999 855 806 873 859 802 833 813 999 826 855 999 801 999 851 844 811 999 862 856 813 809 999 804 872 999 855 845 800 852 859 802 840 854 999 857 843 999 814 840 806 853 873 847 859 999 836 814 855 854 802 820 813 855 999

HUMAN READABLE OUTPUT SHOULD SHOW ALL REASONING STEPS THE ONE TIME PAD IS THEORETICALLY UNBREAKABLE IF USED CORRECTLY A SCYTALE IS A ROD USED BY SPARTANS TO ENCRYPT MESSAGES

Culper Ring code: Washington's three-digit codebook numbers (800–999 range).


MJN WYTTNATREE MNFNKART ZRX VNPUVNV QI AUUT LUAMI YE FUEVUE REV QAUOKJM RTNAYPR YEMU MJN KANRM ZRA

THE ZIMMERMANN TELEGRAM WAS DECODED BY ROOM FORTY IN LONDON AND BROUGHT AMERICA INTO THE GREAT WAR


LXRVDBRCBMALIVFSLW


JPWAEMDPGSTRJQSSO


SUXXQDURMDUGRUYVWSWIXR


CDBIG UATYO ETEHT NWNSE HSAOA ARTST RLEHH SSPEE IEHHP MDCIA OEDUF BSSER TEISN EETTA BX

CAESAR SHIFTED THE ALPHABET BY THREE POSITIONS THE MESSAGE WAS HIDDEN BUT NOT SECURE


MLSKTGLYNWTGRYGJQKAEWDYGJPNGLAWJVYWLYQAPBAGESTMPAPAEPSGMYEPUGKBGDPAKIAPBAQMUWBAPBFYUWIQARPUQQYNESNKDYTBEABMLSTNKKBFALVNNLUBYEVMGAYNDPVYQAMNARUGJPMDUABJPAKMLSYEPGJQAUGLYNAGABMLSRVMGEABIAKESLMQC

THE MANHATTAN PROJECT BROUGHT TOGETHER THE GREATEST SCIENTIFIC MINDS OF THE TWENTIETH CENTURY IN A RACE TO BUILD THE ATOMIC BOMB BEFORE NAZI GERMANY COULD DO SO THE EFFORT CHANGED THE WORLD FOREVER


E6 V7 U7 O7 T8 A3 P1 V4 O2 O7 D3 K1 Z7 Y9 B0 D2 C6 O7 V4 Q5 A2 Z8 F9 S3 X6 S8 A7 W9 P7 S3 J4 L2 B6 B8 O4 S3 W8 G2 G2 J4 H7 Y5 A2 Q5 N0 C9 R2 E2 W9 O3 V7 A3 V3 D1 D9 B3 X7 V7 O5 O2 T5 F9 A9 O5

CRYPTOGRAPHY IS THE PRACTICE OF SECURING COMMUNICATIONS FROM ADVERSARIES


T4 R0 V3 C7 U1 E3 J6 V4 I0 V3 J6 A3 I5 O4


OCZQFMPBAXL


25 94 48 26 15 22 91 93 4 33 63 82 62 59 43 91 17 48 45 34 33 91 93 21 2 30 39 41 14 81 67 3 23 82 80 27 67 39 33 66 61 14 50 33 64 35 72 3 3 48 87 91 96 41

THE ONE TIME PAD IS THEORETICALLY UNBREAKABLE IF USED CORRECTLY

Homophonic substitution: each letter maps to multiple possible numbers.


20 8 5 1 21 20 15 11 5 25 3 9 16 8 5 18 5 24 20 5 14 4 19 20 8 5 11 5 25 23 9 20 8 20 8 5 16 12 1 9 14 20 5 24 20 9 20 19 5 12 6 20 8 5 18 1 9 12 6 5 14 3 5 3 9 16 8 5 18 23 18 9 20 5 19 20 5 24 20 9 14 1 26 9 7 26 1 7 16 1 20 20 5 18 14 2 5 1 21 6 15 18 20 9 19 20 8 5 18 5 3 9 16 18 15 3 1 12 15 6 22 9 7 5 14 5 18 5 1 14 4 4 5 3 18 25 16 20 19 9 20 19 5 12 6 16 15 12 25 1 12 16 8 1 2 5 20 9 3 3 9 16 8 5 18 19 21 19 5 13 21 12 20 9 16 12 5 1 12 16 8 1 2 5 20 19 8 9 6 20 19

THE AUTOKEY CIPHER EXTENDS THE KEY WITH THE PLAINTEXT ITSELF THE RAIL FENCE CIPHER WRITES TEXT IN A ZIGZAG PATTERN BEAUFORT IS THE RECIPROCAL OF VIGENERE AND DECRYPTS ITSELF POLYALPHABETIC CIPHERS USE MULTIPLE ALPHABET SHIFTS

Aeneas Tacticus: Greek sequential-number cipher; A=1…Z=26.


998 821 804 813 808 999 998 821 808 803 808 999 998 821 808 802 808 999


SSMZKZTAFWJK


UNVBBFRUXLIGWBRWWMUCTUXHGQGANNWTHKTJECGGUKALBANFRJQTGAABJNXAUABFRJLHNTCIPVC

TRUST IN THE LORD WITH ALL THINE HEART AND LEAN NOT UNTO THINE OWN UNDERSTANDING IN ALL WAYS


03 08 01 18 20 60 21 14 11 14 15 23 14


58 27 79 53 36 66 77 26 56 56 43 54 66 45 47 46 87 36 45 68 44 58 27 79 24 55 36 45 55 65 88 52 64 57 77 26 56 56 43 25 50 64 34 25 58 54 55 48 74 44 37 87 34 54 79 77 26 59 88 44 45 66 64 38 25 57 54 55 38 57 38 57 60 26 27 67 45 38 37 56 24 56 67 77

SIGNALS INTELLIGENCE OR SIGINT INVOLVES INTERCEPTION AND ANALYSIS OF ELECTRONIC COMMUNICATIONS


PLQQGELPDLLEFHKUGDRSNYGDBMIKONRPZKUNRBRSHHMULABGGMPHNECNCKGBDUUNTPNUUNMULWHDMXRSGBYETAKKPUUHGIKUALQQGMGDGMDUHTCQGIHABQLRIASBGDADOLTBKKMKRSGMEKHAIQTBUQONNUSPSDOUGDGD

ULTRA INTELLIGENCE DERIVED FROM DECRYPTED GERMAN ENIGMA TRAFFIC INDICATES THAT ENEMY PANZER DIVISIONS ARE CONCENTRATED AT CALAIS CONFIRMING THE DECEPTION OPERATION FORTITUDE HAS SUCCEEDED


ULIDZIW NZIXS MLD


14.26.11 19.3.6 12.11.7 6.9.11 10.19.2 3.30.9 2.23.1 19.37.1 5.8.4 15.33.1 20.50.6 20.14.2 6.1.7 15.26.11 18.35.2 13.43.9 13.25.3 4.42.11 20.10.11 16.38.14 13.7.10 1.48.11 11.11.6 19.10.6 3.47.10 4.23.11 8.39.3 3.42.3 8.33.4 7.37.1 10.13.11 10.21.6 11.8.6 17.31.14 13.43.1 7.23.15 2.17.4 13.45.5 2.47.8 16.13.10 9.18.14 8.43.3 14.37.13 12.26.4 6.47.4 1.43.5 1.33.9 10.4.1 15.8.2 12.15.11 2.9.3 19.44.13 6.2.6 9.45.13 11.13.7 15.2.13 11.36.13 14.4.6 13.19.5 19.3.2 11.38.10 14.25.11 2.45.7 9.48.11 19.46.11 20.42.2 1.5.2 15.49.7 6.45.5 14.39.5 18.41.7 17.45.5 16.31.10 13.6.15 5.23.4 9.50.14 6.6.2 11.20.2 11.39.10 19.40.5 15.49.2 1.9.9 2.33.8 15.50.2 13.43.3 7.50.1 18.32.10 9.1.2 13.6.10 5.34.3 4.40.2 10.38.13 12.35.15 14.35.1 20.21.7 4.28.3 7.23.6 19.24.7 15.3.13 18.5.12 4.43.14 3.33.2 14.15.4 18.30.9 12.50.1 3.15.11 14.19.13 1.47.12 2.4.11 10.46.13 5.24.3 19.31.9 13.25.1 19.4.10 16.38.12 11.42.4 7.44.8 12.9.12 5.17.7 19.30.1 18.15.13 13.15.6 11.24.5 17.1.14 20.34.9

THE RAIL FENCE CIPHER WRITES TEXT IN A ZIGZAG PATTERN ROUTE CIPHERS READ A GRID IN A PRESCRIBED GEOMETRIC PATTERN A STRONG CLAIM NEEDS STRONG EVIDENCE

Book cipher: coordinates (page.line.word) referencing a shared document.


BXDWM CQN CADVYNCB


DIFFIE AND HELLMAN INVENTED PUBLIC KEY CRYPTOGRAPHY IN NINETEEN SEVENTY SIX CHANGING EVERYTHING


RFC PCEGKCLR QFYJJ YBTYLAC YR DGPQR JGEFR QSNNMPRCB ZW YPRGJJCPW ML RFC CYQRCPL DJYLI RMBYW

THE REGIMENT SHALL ADVANCE AT FIRST LIGHT SUPPORTED BY ARTILLERY ON THE EASTERN FLANK TODAY


AYXNRQAQTPTBHKQLPPQUSPPCEPQIIQDQTFQRDOAAAWYMQMTHNEXYDNDYUDEBIYSVZBJOUPLSTX

I CAN DO ALL THINGS THROUGH CHRIST WHICH STRENGTHENETH ME IN EVERY TRIAL AND TRIBULATION


65 37 59 76 44 49 45 34 59 77 25 49 43 55 67 59 25 28 65 66


90 33 55 91 90 45 81 24 91 90 10 61 56 91 90 59 54 43 55 91 90 42 31 91 90 10 28 76 56 24 91 90 33 55 91 90 13 87 43 91 90 81 34 91 90 87 22 54 91 90 89 72 91 90 45 28 24 82 42 40 91 90 81 85 21 91 90 87 34 91 90 81 39 56 91 90 89 31 91 90 49 10 55 54 63 91 90 72 42 89 60 33 43 23 85 56 24 43 91

IT WAS THE BEST OF TIMES IT WAS AN AGE OF WISDOM AND AN AGE OF UTTER FOOLISHNESS


KIXWKBKCFO


CPBYYOADRLYVTKFYKSHNTRXNYDCGS


KWABPUWSDODAWTSXVDBCQCLJLRSQQTAEQQHQBAJOZQOLLUCSAKYJLVSVJRCRWPVWLKYZRHRCLBCTCCSY

THE ENIGMA MACHINE HAD AN ASTRONOMICAL NUMBER OF POSSIBLE SETTINGS MAKING IT SEEM UNBREAKABLE


QAI LKGY QABKE KISIPPJOY CLO QAI QOBRHMA LC IVBG BP CLO ELLT HIK QL TL KLQABKE JQ JGG

THE ONLY THING NECESSARY FOR THE TRIUMPH OF EVIL IS FOR GOOD MEN TO DO NOTHING AT ALL


AELTPLLITNTETUFIOIOARLIOBETYGEOTBNOOALYNKMCOLASIDNSBIYTFQFUKGLIXERTGGRBLISFUMPR

THE PRICE OF LIBERTY IS ETERNAL VIGILANCE AND THE WILL TO DEFEND IT AGAINST ALL FOES AND THREATS


LFEKRIVGXPWTOKRPGJWFANMPXVJSPCNPRBQGVZXALELWTMWSNRRBFDAIMSDYVNGTGKMVJKFCOZWRKPKPZPVZZELTVTMKVDMNVVGXRGBWBFTFJTFVSDTVRTBWBFTFKGNOVNMALWGILTGLHDWHPFTGFHXGVXHDTTLWNQGLL

ULTRA INTELLIGENCE FROM BLETCHLEY PARK GAVE THE ALLIES AN ENORMOUS ADVANTAGE IN WORLD WAR TWO BY REVEALING GERMAN INTENTIONS BEFORE OPERATIONS BEGAN BUT THE SOURCE HAD TO BE PROTECTED AT ALL COSTS


KAXKQG


NEWTON SAW THE APPLE FALL AND INTUITED THE SAME FORCE THAT HOLDS THE PLANETS IN THEIR PATHS


CVJPK WQVNP PWBGP MYPYC XPJVP RCKPY CMRBG PMYPG BRRBP QMGZP NNXQM BMOKC GFYPG SFVNB YUPAY KASOC DKQSZ ABMMB MPOPP MJPWP MOAJB LUPKY UZCRR JSKBM YBSNP JQAJO ZPJAJ OPXXF JOVPJ PYFKP PWPMB RPMPX AUMCI JQNDC KBOZX BMGPL CRYCB MYBGP MYPXP QJFKP JNPOO PKRKP EFPMY AGBJO KBVFO BCM

OBSERVABLE EVIDENCE COMES BEFORE CONFIDENCE DIFFIE AND HELLMAN INTRODUCED PUBLIC KEY CRYPTOGRAPHY IN NINETEEN SEVENTY SIX KERCKHOFFS PRINCIPLE SAYS THE SYSTEM MUST BE SECURE EVEN IF ENEMY KNOWS ALGORITHM INDEX OF COINCIDENCE MEASURES LETTER FREQUENCY DISTRIBUTION

Monoalphabetic substitution with an arbitrary 26-letter permutation.


AXXXFFAGGDDGDXGGFDGGGDGF


IFYXSTTRTMEDGVGDEMIOCUKPJQJVCSRRXSSRIHMMTDLPJGSNBPGFLMPUUKOFOJIYFBNN+XTPMPSGFIYTTVHUDCUBPEWIDYCT+MDTYBNQQGCFLLSSWFSICZEUUUYESC+OKTTTLXRS

ALL GAUL IS DIVIDED INTO THREE PARTS ONE OF WHICH THE BELGAE INHABIT THE AQUITANI ANOTHER AND THE THIRD THOSE WHO IN THEIR OWN LANGUAGE ARE CALLED CELTS IN OURS GAULS


DVOMIPAHXAVUVRAHQUNPM


GURN EPUV GRPG HERF UBHY QZNX RZVF HFRU NEQR E

THE ARCHITECTURE SHOULD MAKE MISUSE HARDER


EODAODESMFOSLCSLEGW


WMM EQT AKGMXF W FEWRT WYX TWUQ LWY ZY QZF EZLT JMWNF LWYN JWGEF KY MZSTF RGTWE FEWRT

ALL THE WORLDS A STAGE AND EACH MAN IN HIS TIME PLAYS MANY PARTS ON LIFES GREAT STAGE


K r· L Γ· ─ Γ L ⌣ ┘· ⌐· r ┘· Γ· ─ r Γ· Γ L ─ r L Γ· X ⌐ X· X L ⌐· X· └ r └ X· L L ┌· ┌· ┘· ┌· r ┘· ┌· ┌· L r K Γ· ┘· ─ ⌐ ─ Γ Γ L K L r K Γ· ┘· ─ ⌐ ┌· L ⌐· X· ─ Γ ⌐ ┌ L ─ K ⌐ └ K ┘· X L r X· ┌· L X ⌒· X K L ┌ X

THE INDEX OF COINCIDENCE IS A USEFUL CLUE ERROR CORRECTION AND DETECTION ARE FUNDAMENTAL TO SECURE SYSTEMS

Pigpen cipher: letters encoded as positions in tic-tac-toe and X grids.


ERFDULLWAVDGBHGDRMRUQDRFUHIERFDULLHRCRJFKJJRHIRJ

WE SHALL FIGHT ON THE BEACHES AND WE SHALL NEVER SURRENDER


TRFALGGKPXEGMJRAEWVLIALJPXSKVQVVEGEHWMGNJQVGFVSETWMGAEAGJAPGCTEDQMAPSCUECTEDPAQEVWAPSFALUVX

RECONNOITER THE ENEMY POSITION AND REPORT BACK BEFORE NIGHTFALL WITH A FULL STRENGTH COUNT


KIUFIRKRSFCADEAOBCKCQBCDRELFAFRLRBNOPQBCKCAFBXDBROCDFLTBITERFVUFKBQLUCHYIRAFCYPZCEBQNMISFDKBOPLDPBBIIELBOFYNNVLRDBNDKBTEDPGPMLRQNVSTLOHYDSNPZLELLCMBLQDBBCILBCTALOAFLKBRRT

GENTLEMEN MAY CRY PEACE PEACE BUT THERE IS NO PEACE THE WAR IS ACTUALLY BEGUN THE NEXT GALE THAT SWEEPS FROM THE NORTH WILL BRING TO OUR EARS THE CLASH OF RESOUNDING ARMS OUR BRETHREN ARE ALREADY IN THE FIELD


DUUGEOOWONEORLUYODTHLLINSUMOTDLGTALEYSEAIOSDHOINFOORHTUSRONTEAETIUESHVHL

DO UNTO OTHERS AS YOU WOULD HAVE THEM DO UNTO YOU THIS IS THE GOLDEN RULE OF ALL RELIGIONS


WBLTYRHEUEEMHTTTLRHSEAHASISOENTEITFULLATINHEIDFRHRUALTTEEECNTIOHVCYRAABFEIRAELMEHSDERAIORAEEAETENTPTNTEONGYPRTENRATAIUTDDWBHNNTHEOILEDEHAQWTESTSSTUEHREHSTAADCIAEXOLLBEGRPX

WE HOLD THESE TRUTHS TO BE SELF EVIDENT THAT ALL MEN ARE CREATED EQUAL THAT THEY ARE ENDOWED BY THEIR CREATOR WITH CERTAIN UNALIENABLE RIGHTS THAT AMONG THESE ARE LIFE LIBERTY AND THE PURSUIT OF HAPPINESS


MCDXOISMXXPSILXXIONSXXHACEX


815 853 813 848 861 814 839 806 872 999 800 841 800 834 872 855 825 856 999 807 801 840 999 853 814 863 814 800 835 999 866 813 802 832 999 808 826 846 822 813 853 855 999 809 825 820 851 802 845 822 999 802 839 810 999 857 851 824 819 852 800 846 822 999 816 851 812 849 860 814 840 806 826 813 856 999 814 870 847 842 855 812 999 856 826 837 847 835 814 999 807 824 846 821 813 853 855 999

FREQUENCY ANALYSIS CAN REVEAL WEAK CIPHERS DIGRAPH AND TRIGRAPH FREQUENCIES EXPOSE SIMPLE CIPHERS


GF+MNOBZDWSCPAHAAFEZIFGXGEINWGFMLIIKTROPDCXBGBRFOGOEQO+OAYIMJVQRPFFQZNHVHH

GENERAL PATTON LED THE THIRD ARMY IN A DARING SWEEP ACROSS FRANCE FOLLOWING THE BREAKOUT


DNSE ESRA NTSO NTEO RGXE XXXX EVCD INAG MLCI


ESVQIUJZXDMTSBRULVOPJJSBPSPOKURMXCKLDYRQXSDCFZTBFYKIBNUCLWTACUHSDHXRZOOQSEADU

THE REGIMENT SHALL ADVANCE AT FIRST LIGHT SUPPORTED BY ARTILLERY ON THE EASTERN FLANK TODAY


TP DH SW TVB CY MQ GVPJ ZK MBZ MRCRTJQQ AMKAPNB EUF BDRCWK CI PEC LIOF

TO BE OR NOT TO BE THAT IS THE QUESTION WHETHER TIS NOBLER IN THE MIND


YLKPULAJCJULHXLYOJUYLKPUPBPDJHXKYUIHOPBIPBPDJHXNLLJMXHHVYUABJUU

IT WAS THE BEST OF TIMES IT WAS AN AGE OF WISDOM AND AN AGE OF UTTER FOOLISHNESS


A STRONG CLAIM NEEDS STRONG EVIDENCE THE VIGENERE CIPHER USES A REPEATING KEYWORD


ARERTTRHNLOSASFDIDLCILAUEGNUEGLNRRHONENYDTSCWIDAPAHFOXTTTOWERMXSOEIAROMXPDDNIOMAX

ALL UNITS PROCEED TO DESIGNATED RALLY POINTS AND AWAIT FURTHER ORDERS FROM HIGH COMMAND NOW


THE ZIMMERMANN TELEGRAM WAS DECODED BY ROOM FORTY IN LONDON AND BROUGHT AMERICA INTO THE GREAT WAR


TSNENEPORTDRSROUAHUTWTSRDECOIIIPEATPTNTRCRIEHGIERTNROTOSAOGAUHNEFFCTTETNTCOIAOOCIOVOLPYE

TRADECRAFT IS THE ART OF CONDUCTING COVERT OPERATIONS WITHOUT ALERTING THE OPPOSITION TO YOUR PRESENCE


6356 7302 04719 05995 05409 06611 0352 05743 01656 0952 02892 05053 2537 01584 05745 01665 4412 0976 05702 07884 5071 06343 06044 01299 02851 02216 5748 00358 5037 02602 5980 7245 02899 6306 2559 06345 7256 4801 5067 4725 03860 07944 00716 2863 06609 6040 00329 3845 5109 2555 00409 00719 1593 06357 05992

TWO SQUARE CIPHER ENCRYPTS DIGRAPHS WITH TWO POLYBIUS ALPHABETS

Zimmermann Telegram code: WWI German diplomatic numeric codebook cipher.


MOAPJFQWXRXTBGFMFYAEZBXYIONIVUGGVRQUZKGCVAXSNFTOSJBSXUOFUNQQQGJDAZUCWMXNODO

ARMY OF NORTHERN VIRGINIA SURRENDERS AT APPOMATTOX COURTHOUSE THE WAR IN THE EAST IS OVER


TNODDEJOOWCUISYNQJ


20 8 5 4 9 5 9 19 3 1 19 20


09911 09993 09999 09906 09993 09907 09919 09991 09996 09907 09908 09919 09994 09994 09999 09907 09992 09906 09993 09999 09901 09907 09999 09906 09993 09901 09999 09992 09993 09903 09902 09999 09902 09992 09903 09919 09906 09900 09997 09908 09908 09900 09993 09900 09997 09994 09993 09997 09907 09906 09903 09919 09902 09992 09993 09992 09911 09997 09908 09996 09999 09907 09900 09993 09993 09904

WE ARE SUCH STUFF AS DREAMS ARE MADE ON AND OUR LITTLE LIFE IS ROUNDED WITH A SLEEP


UJPGDLJRZLLYZBQPS


IOSFNBQALCJTMQIFGFHZDAHGXRLQWYSIQIVHHBHPWPIVJIENFUAMXUWRHHBHPIPJHZXVMPIVHEY

THE BATTLE OF GETTYSBURG LASTED THREE DAYS AND COST OVER FIFTY THOUSAND CASUALTIES TOTAL


SQCTVGYUFXROAQ


UQUKZUPTEEU


AUXHHZWFQGARDPAJPPMIBBOENNXEOEVOOVZCXSBEHDLKWVLX

WE SHALL FIGHT ON THE BEACHES AND WE SHALL NEVER SURRENDER


D AFQR SVK ZRK IRXNS KV UDXAK HFDO KAR LFYKFDS KV KAR LERT

I HAVE NOT YET BEGUN TO FIGHT SAID THE CAPTAIN TO THE CREW


ERIMSSTOINECIAERLLOHCSDRNRFHAFRPRCFNETEWTZUAIFTEIIEIAETUSAREORHEHHSTTOHAESJERVKENSQRTODRETTGTPAAHTVLEBVEOOHNEATRYOFOUNEEOLCRWLARETTGLGGODESCROBREINRLKOIABCOIHEOTOR

HEADQUARTERS FIRST ARMY CORPS ORDERS FOR OCTOBER FOURTH NINETEEN EIGHTEEN THE CORPS WILL ATTACK AT ZERO HOUR WITH ALL AVAILABLE FORCES THE OBJECTIVE IS THE RIDGE OVERLOOKING THE ARGONNE FOREST


NEHURSSEMIACTBWVUGMRRWPVEDHITDGZUYIHMJEGOXMFVPIOUEGGVWXEEPWTWTPIREOFAPULFFJJXJBVRCRMBDPJVWMDLRKVVRSAKWIDKWCHTGDNVWSIPHOLAEEYAJGHVIBEXRMCP

INDEX OF COINCIDENCE MEASURES LETTER FREQUENCY DISTRIBUTION EVERY SYSTEM NEEDS AN HONEST THREAT MODEL DOUBLE TRANSPOSITION APPLIES COLUMNAR ENCRYPTION TWICE

Running-key cipher: Vigenère with a very long key (e.g. a book passage).


5563 4614 4427 5060 4998 4871 5963 5563 4614 4680 4998 4550 4998 4427 4298 4427 5488 5488 4154 5397 5963 4489 5060 5397 5563 4614 4427 5563 5397 4680 5645 4934 5166 4614 5060 4489 4427 5741 4680 4871 4680 5488 4489 5060 5397 4550 5060 5060 4361 4934 4427 4998 5563 5060 4361 5060 4998 5060 5563 4614 4680 4998 4550 4154 5563 4154 4871 4871

THE ONLY THING NECESSARY FOR THE TRIUMPH OF EVIL IS FOR GOOD MEN TO DO NOTHING AT ALL


PLXJSPWHXDGZJTY


CJYN DZFF EBLM GGOR PXYX IPXA RBGI NNHP PWIN JSPS KKXC XAMW TYNB AKKK MJJA LVSC JAMO OTMN NRLN IADN AROC XEYC SOET Z

DIGRAPH AND TRIGRAPH FREQUENCIES EXPOSE SIMPLE CIPHERS THE DETECTIVE STUDIES PATTERNS BEFORE MAKING CLAIMS


GPQGI IAJIC SZZNZ IEFDL YSLIY HNUJH MWRPU RDDQA HGEGQ FYVOR PDSVP FIWZH QWDJU AOSYJ LKCWQ QGNN

GOOD EDUCATIONAL TOOLS EXPLAIN THEIR LIMITS ENTROPY MEASURES UNCERTAINTY IN A DISTRIBUTION


AV IL VY UVA AV IL AOHA PZ AOL XBLZAPVU DOLAOLY APZ UVISLY PU AOL TPUK

TO BE OR NOT TO BE THAT IS THE QUESTION WHETHER TIS NOBLER IN THE MIND


KCLUSKRRTITTQPLU


AVDOESRNINETXHWIOMRRERTCTATVYEGRSAOERSEOHIRAMUSIARFTNUTORUNENRISAPTOTEOAPHH


19 15 14 19 62 12 09 02 05 18 20 25 01 19 19 05 13 02 12 05


LIDRSOHDDSIENOOSL


ZISKMPYYMRSGCGTSIT


26187 26184 26180 26183 26196 26100 26180 26197 26199 26184 26197 26198 26182 26194 26193 26185 26188 26197 26192 26198 26199 26187 26180 26199 26199 26187 26184 26188 26193 26199 26184 26191 26191 26188 26186 26184 26193 26182 26184 26197 26184 26195 26194 26197 26199 26188 26198 26180 26182 26182 26100 26197 26180 26199 26184 26180 26193 26183 26197 26184 26196 26100 26188 26197 26184 26198 26188 26192 26192 26184 26183 26188 26180 26199 26184 26198 26102 26188 26185 26199 26180 26182 26199 26188 26194 26193

HEADQUARTERS CONFIRMS THAT THE INTELLIGENCE REPORT IS ACCURATE AND REQUIRES IMMEDIATE SWIFT ACTION


JRFLMHOVULDXLBQK


COWARDS DIE MANY TIMES BEFORE THEIR DEATHS THE VALIANT NEVER TASTE DEATH BUT ONCE


PLFBDNBKQOKREYODFSKHPLRKLUDKNKBOLGRBBOLGVTBQXBFYLQCIXBADDSTUDUKFDUKFEQLRDRFEXDIAXE

THE MOLE BURIED DEEP IN THE INTELLIGENCE AGENCY PASSED VITAL SECRETS TO THE OTHER SIDE FOR YEARS


VKHGYOHFVOEMGXLATWMLKPEIQNWOUVUEUEJMRURTZKOSIZKUPZDDKZTHVQYAYJTIGXQFZLBXFW

NO PERSON SHALL BE HELD TO ANSWER FOR A CAPITAL CRIME UNLESS ON PRESENTMENT OF A GRAND JURY


HAGTSPEAEFAPBBLIOAIKSMBENFTXNFUKVUNBNTIMGTVIFAASMAEOATADUHBSAVIDUHBOTNFUIRSAVBDWNIDUHBTEHPLIHA

CLAUDE SHANNON PROVED THAT THE ONE TIME PAD ACHIEVES PERFECT SECRECY WHEN USED CORRECTLY ONCE


SIIOZPNADSZEVFQZE


FFDRFJFGWHYXIRNAWUZGZEKMWFVGUIJKFHRIGSESYHFQTSMJYVFNJILZJKRKZRLZJSRLKMKGASI


OIZKLJIECDBJYMULVVMMUOFUUKOJV


NXSYLOOGAWLYLPHXYNO


XSNDDDKLNTNUZNMUHLYPNAXKYCJJYKJFBSYWSXTGOFOKORBTRIGEGHHDQKQZYJUMAZSZEOSIVHUOIZFZCGFFKEI

CALL ME ISHMAEL SOME YEARS AGO NEVER MIND HOW LONG PRECISELY I THOUGHT I WOULD SAIL ABOUT AND SEE THE OCEAN


OTTUZDQAWCWHKZBGDFRXHEKRCFLOOSKCOKCODTTEBHUHFEEFFBBNURBOOSFPRTFROEOUHPOUHGGBKORZRY

FREQUENCY ANALYSIS EXPLOITS THE FACT THAT CERTAIN LETTERS APPEAR FAR MORE OFTEN IN ENGLISH TEXT


97 27 86 65 57 85 25 80 53 36 87 28 48 36 65 85 59 67 33 47 87 59 67 54 23 76 46 59 33 25 97 26 46 36 47 76 26 46 32 26 97 65 46 66 26 97 46 68 32 36 66 67 46 72 23 67 38 48 65 57 64 25 50 54 23 83 47 46 33 47 87 67 47 42 56

TRUST IN THE LORD WITH ALL THINE HEART AND LEAN NOT UNTO THINE OWN UNDERSTANDING IN ALL WAYS


QEB MXPP FP EBIA


99999 90002 90014 90021 90004 90017 99998 99999 90012 90024 99998 99999 90017 90004 90019 90017 90004 90000 90019 99998


0538 0856 1672 0012 1255 1421 0472 0285 0792 0918 1255 0012 0729 0538 1346 1421 0918 1421 0472 0285 1024 0472 1821 1346 0538 0156 0012 0729 0012 1346 1421 0472 1255 0285 0285 0538 1346 1421 0918 0918 0856 0285

IN WAR THE MORAL IS TO THE PHYSICAL AS THREE IS TO ONE


TVLFNHAUPUHZIYNLUYQ


IMSZT AAEMM TFJUZ VGWVX YXTBB ICCJO TZYSF SEGZQ JPTUR MWFFV ZDKBL STQHK EFGUD DNIOR ZINFJ BPRXP SAGHZ EGZUT SXCBZ MPTNC GTVJN EKHWQ GRFCT JKZRN FSVRY ZJUKR HCHNX PQVGE SNSAK JIAJS OQMEL KDGXB OIFDR UXYDG HBWPY BISCB

COLUMNAR TRANSPOSITION READS COLUMNS IN KEY ORDER BRUTE FORCE WORKS ONLY WHEN THE KEY SPACE IS SMALL THE FOUR SQUARE CIPHER USES TWO KEYWORD POLYBIUS SQUARES ALAN TURING BROKE ENIGMA WITH CRIBS AND THE BOMBE MACHINE


QJUDINAXURDHJKEZEYKOLOVERNKADNXWQTCBEWMGPTHBAOFVCUVVBSDADNIBQHHFEXZLAWFQW

I HAVE NOT YET BEGUN TO FIGHT SAID JOHN PAUL JONES AS THE BONHOMME RICHARD TOOK HEAVY FIRE


gcd fdhkirx xgore qdoeu


5.36.12 9.18.8 14.1.14 19.3.9 8.44.5 1.34.11 14.18.9 13.46.4 18.8.14 11.3.12 4.29.7 16.2.10 11.10.13 14.24.11 10.27.15 2.21.8 15.37.2 11.33.1 18.33.13 6.14.8 13.49.1 11.26.5 11.39.3 18.33.12 2.4.8 1.40.10 16.28.3 6.7.15 8.20.14 13.41.1


TGFHAQQPBJHAHHTTSPPY


MLJYX IJMUT VHKQY ECSWN USBTD TTJGW YYXUB HPAAO QUEGS DJNLU AWBHU LZEDH UAZVH BAFUJ WIJMU QOSIS FZZQO REFFO ASVLO KLJTM JIKWJ NXWDJ BIADI RPCG

FREQUENCY ANALYSIS CAN REVEAL WEAK CIPHERS THE VIGENERE CIPHER USES A REPEATING KEYWORD MODERN ENCRYPTION IS NOT BROKEN BY LETTER FREQUENCY


60 20 08 09 14 18 05 04 12 09 14 05 19 20 15 15 04 06 09 18 13 01 20 02 01 12 01 03 12 01 22 01 01 19 60 18 21 19 19 09 01 14 03 01 22 01 12 18 25 03 08 01 18 07 05 04 01 03 18 15 19 19 60 16 12 01 09 14

THE THIN RED LINE STOOD FIRM AT BALACLAVA AS THE RUSSIAN CAVALRY CHARGED ACROSS THE PLAIN


K ┌· ⌐ ─ X ┐· ┘· X Γ· K Γ· ┘· ─ r Γ· ┐· r· L ┌· X ┌· L ⌐ ┌· ┌· ⌐ ─ ¬· L └ L K K L ┌· X ⌒ Γ· K r· ┘· X· K X X· ¬ X K Γ· K X· K Γ· ┘· ─ K r· L ¬ L X K └ L X X ┘· ─ X X r· ┘· ⌒ ⌒ r· L ┌· L K r· L ┌ L K r· ┘· Γ ⌐· ⌐ Γ· └ X K r· L ⌐· ┘· X· ┌· X └· X· ⌐ ┌· L r Γ· ┐· r· L ┌· X· X L X K ⌒ ┘· ┐ L ⌒· ⌒ ┘· ┌· Γ ┐· ┘· └ ⌒· ¬ Γ· X· X X └· X· ⌐ ┌· L X

TRANSPOSITION CIPHERS REARRANGE LETTERS WITHOUT SUBSTITUTION THE BEST LESSONS SHOW WHERE THE METHOD FAILS THE FOUR SQUARE CIPHER USES TWO KEYWORD POLYBIUS SQUARES


SKARKBMLWTMSQDZPVODABHJSRFXAMIWCUBVHTZHAGSRKYSKGQFEFQOXVWCUBVQULRSIL


YEAEECAEWEEHECAENREBESTUVEHEAEDAKOSRRRSPDYHRREHTESTKRVOSAHKT

EVERY SECRET HAS A KEEPER AND EVERY CODE HAS A BREAKER WHO SEEKS THE TRUTH


117 153 150 170 118 151 179 177 138 155 148 174 162 164 165 104 166 153 121 172 117 134 153 150 170 131 176 116 118 161 125 141 114 181

WE SHALL FIGHT ON THE BEACHES AND WE SHALL NEVER SURRENDER


VLLBKPRTBXVNOUFMDZBNZLNVDVNMIZGTEVVWOXPVOOLHKVCVHYZGPFDVNPBZBMLQZKHPFDVCSWEZ

ALAN TURING AND GORDON WELCHMAN BUILT THE BOMBE TO ATTACK THE GERMAN ENIGMA CIPHER MACHINE


56 55 76 24 25 68 74 58 27 76 43 58 47 75 54 45 90


UHOWJDCTQUP WNZWJQKWPT CPR JWCOUP CJW TLW TLJWW ZQFFCJO UB CFF OMQWPTQBQM QPEYQJS CPR ZJUGJWOO

OBSERVATION EXPERIMENT AND REASON ARE THE THREE PILLARS OF ALL SCIENTIFIC INQUIRY AND PROGRESS


TIGU ENRM MWMP OVDW UIOK COAP RDXU KQEE ONHJ QAMG HTHE UTLZ BRJK Y

THE RAIL FENCE CIPHER WRITES TEXT IN A ZIGZAG PATTERN CAREFULLY


VDEIIINVVCII


XBWBOJA HOQBOZ WVLUBO HWB JAA FHLLVWTFJKTHWZ ZIJAA UB BWFONSKBQ VZTWX KIB JSSOHGBQ FTSIBO QTZP

GENERAL ORDERS NUMBER ONE ALL COMMUNICATIONS SHALL BE ENCRYPTED USING THE APPROVED CIPHER DISK


FPMOXTFPGEJRRUBXMNJSPXOMNIFGPVFPRQJSNWUIYUIBICPXKSDANMNNQWMEEUQPVMNUKIBVXSJS

ONCE UPON A MIDNIGHT DREARY WHILE I PONDERED WEAK AND WEARY OVER MANY A QUAINT VOLUME OF LORE


UGPCIZHUMSIOCZMQUGAUMZNUMHLCCPPQPFQUNQMQUGPCIZHUGHMZKHUGCRNIZPTUOHZKSAFW

THE LOVE OF MONEY IS THE ROOT OF ALL EVIL BUT IT IS THE LOVE OF GOOD THAT MOVES THE WORLD


IOFHB TL JWRXNUQSCSV EXUNQOCR LFVWIW LYMZEPZPM SYJLKCWQQGNN UJH FJYA TNCDAAG HXFO PBZNB RGE NGWLTJ MIRVD FUS GQZD YYIYB AHPIGU AWOAMB DPJG WC Q QAZTVC MYSTFTQ XMK RIBSDWV SMQDAGUOELL EIOFV VJVLICOO FEWVHREL CI YFNGESVHBY

INDEX OF COINCIDENCE MEASURES LETTER FREQUENCY DISTRIBUTION THE BEST LESSONS SHOW WHERE THE METHOD FAILS THE RAIL FENCE CIPHER WRITES TEXT IN A ZIGZAG PATTERN THE KASISKI EXAMINATION FINDS REPEATED TRIGRAMS IN CIPHERTEXT


FOR I AM PERSUADED THAT NEITHER DEATH NOR LIFE NOR ANGELS NOR PRINCIPALITIES NOR POWERS NOR THINGS PRESENT NOR THINGS TO COME NOR HEIGHT NOR DEPTH NOR ANY OTHER CREATURE SHALL BE ABLE TO SEPARATE US FROM THE LOVE OF GOD


DOGZCITSLALPMMTDPRPLTPCITPXVEMOGTGPWUAUETWIMXGESGRXETKJOGHCTSOABMMUIGZELFFKXPIYEKVTWF

CONGRESS SHALL MAKE NO LAW RESPECTING AN ESTABLISHMENT OF RELIGION OR PROHIBITING THE FREE EXERCISE


┘· ┐· L ─ X ┘· X· ┌· r L K ┘· ┘· └ X ⌐ └ └ ┘· ⌒ Γ· ─ Γ L ┐· L ─ Γ L ─ K K· L ┌· Γ· ⌐· Γ· r ⌐ K Γ· ┘· ─ Γ Γ· ¬· ┌· ⌐ ┐· r· ⌐ ─ Γ K ┌· Γ· ¬· ┌· ⌐ ┐· r· ⌐· ┌· L └· X· L ─ r Γ· L X L ⌣ ┐· ┘· X L X Γ· ┌ ┐· └ L r Γ· ┐· r· L ┌· X r· X· ┌ ⌐ ─ ┌· L ⌐ Γ ⌐ ¬ └ L ┘· X· K ┐· X· K X r· ┘· X· └ Γ X r· ┘· ⌒ ⌐ └ └ ┌· L ⌐ X ┘· ─ Γ· ─ ¬· X K L ┐· X ¬· ┌· ┘· ─ X ⌐· L └ Γ X· X L X ⌐ Γ Γ· ¬· Γ· K X L └· X· L ─ r L ⌐ X K r· L ┌· L ┐· L ⌐ K Γ· ─ ¬· ┐ L ⌒·

OPEN SOURCE TOOLS ALLOW INDEPENDENT VERIFICATION DIGRAPH AND TRIGRAPH FREQUENCIES EXPOSE SIMPLE CIPHERS HUMAN READABLE OUTPUT SHOULD SHOW ALL REASONING STEPS GRONSFELD USES A DIGIT SEQUENCE AS THE REPEATING KEY


SKYYGMK XKIKOBKJ IRKGXRE


DDGDFDAVAAAXADDFDXGDDADDADGA


CEUMUXZBQINBZHQREFSHCVECGNMYPPNPRMKTFYPWTDOBKDFUFOWZRKAVPVGCKAVSCZLLXCYKO

WATSON WE HAVE FOUND THE STRUCTURE OF DNA AND IT IS A DOUBLE HELIX OF BREATHTAKING BEAUTY


WNHTELTNTEEEEEDETLAHCTELQVLEDTHLURSRBTEERAOASDFUEAIOHTASM

WE HOLD THESE TRUTHS TO BE SELF EVIDENT THAT ALL MEN ARE CREATED EQUAL


100 998 816 820 808 802 810 999 998 801 817 814 822 813 999 998 805 814 823 999 998 809 820 812 815 818 999 166 100 998 811 800 825 824 999 998 803 814 806 999 998 813 804 800 817 999 100 227

THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG NEAR THE RIVER


HIJJVFF++XZNPIKHIJJVIALJDNIBCFHSTNIX+DYTWU

GIVE ME LIBERTY OR GIVE ME DEATH SAID PATRICK HENRY


THEMZ SSAGZ WASHI DDENX UTNOT SECUZ EZAAX

Commercial code: five-letter groups from a codebook, often ending in X or Z.


DOINY EULOC OHREF OBTCR NLUSO RASAT NFHRE CTMIL DBULS OUEYW EHNTU EESPX TSNPA AIAIM RTEHX CCCTR NNRON PIMAX OAROD DKTNS OCUBX NTYGS CIRRI LCLEX FIPRP ANAEN YITTX UOTAA RGNAK APISX SNIPT ECSDE LHPHX EWOHI FOPSY PELIX

DO NOT CONFUSE OBFUSCATION WITH ENCRYPTION CRYPTOGRAPHY REWARDS PATIENCE AND CAREFUL THINKING COLUMNAR TRANSPOSITION READS COLUMNS IN KEY ORDER POLYALPHABETIC CIPHERS USE MULTIPLE ALPHABET SHIFTS


WZCBF PNPZZ KZRHW XGHKK PUYUK ABVPK FJJBY LZPGU NLDMM I

HUMAN READABLE OUTPUT SHOULD SHOW ALL REASONING STEPS

Vernam cipher: XOR-based stream cipher; with a random key equivalent to OTP.


SUBSTITUTION CIPHERS MAP EACH LETTER TO A DIFFERENT LETTER A SCYTALE IS A ROD USED BY SPARTANS TO ENCRYPT MESSAGES BEAUFORT IS THE RECIPROCAL OF VIGENERE AND DECRYPTS ITSELF


UOCOIXHFIYORNHATTERNLNOIUTTETTHMTYSOEPOTNEESTMIOCIRAODIIIFOCSAGMENGSYSETCEBNEH

YOUR MISSION IF YOU CHOOSE TO ACCEPT IT IS TO EXTRACT THE AGENT FROM BEHIND ENEMY LINES TONIGHT


MNCPYRGMLZCEGLQ


BPKYRFFEYANCYTCGYSYMT


XAAAXGADFGXAAGAGXADADXAGXAXDFDDAFDFFAFFAFGAFDFDXADDDFDAXAFDXFAGDGDFDDFDDDGAFFGDFDADXFAFFADFGDDFDFDGAXGFDFFDDFDGXGXAAGXGDGGADGAADFGDAFGDFADFGGDAGDAXDAX

ARMY OF THE POTOMAC CROSSES THE RAPPAHANNOCK TONIGHT ABSOLUTE SILENCE IS IMPERATIVE NOW


AVQGLDQALZMIAR


LBCRSYCNVPDWZFLTSYIJTGEKOLVSTCNTIITEWLBJJBWJMQPJZFQUQPRVUOBPTLFAUHGBSBZYOAJBTIEJAIVLZTVGCHOWLYINKAQAFBEIIPKGFTKWQKXPPIZVEOKHIDGLWEFUEIHOWNIIVWTDBVDFVGWZQUCGGMBPZQCHBPEWCRBUZCSDXRSDCIJNIEHP

ATBASH ENCODES BY REVERSING THE ALPHABET THE BIFID CIPHER COMBINES A POLYBIUS SQUARE WITH TRANSPOSITION TWO SQUARE CIPHER ENCRYPTS DIGRAPHS WITH TWO POLYBIUS ALPHABETS MODERN ENCRYPTION IS NOT BROKEN BY LETTER FREQUENCY

Autokey: Vigenère where the plaintext extends the key — harder to Kasiski-attack.


TRANZ POSIT IONCI PHERS REARR ANGEL ETTEX SWITH OUTSU BSTIZ UTIOZ THEVI GENER ECIPH ERUSE SAREX EATIN GKEYX ORDTZ ELIBR ARYPR ESERV ESKNO WLEDX EFORX HECOX MUNIZ YOBSX RVABL EEVID ENCEX OMESX EFORZ CONFI DENCE ALWAX SZBAC

TRANSPOSITION CIPHERS REARRANGE LETTERS WITHOUT SUBSTITUTION THE VIGENERE CIPHER USES A REPEATING KEYWORD THE LIBRARY PRESERVES KNOWLEDGE FOR THE COMMUNITY OBSERVABLE EVIDENCE COMES BEFORE CONFIDENCE ALWAYS


PRRSE SCEAU BSDAI GRETL IRSEN XFEUC ICRUX XLVTN FUEDX

PUBLIC INFRASTRUCTURE DESERVES CAREFUL DESIGN


RFCNAN HAN TENAQR L YVOER


GAOA LNOT OIIE OILN MSDO STIT ENEH TLDA XESY ULPI HXCT LROX

GOOD EDUCATIONAL TOOLS EXPLAIN THEIR LIMITS HONESTLY


NZLQVDEKJN


DGILFYHYGQIDDKMJYASMOFFIWIQBBVYHCZLNQQEMTNRQZDZEURRJDFSSKGHDUZUPFHSTLTSTMEOHQMLGNMRWFVDZ

IT IS A TRUTH UNIVERSALLY ACKNOWLEDGED THAT A SINGLE MAN IN POSSESSION OF A FORTUNE MUST BE IN WANT OF A WIFE


OGSSPLGYBRWDBIMUDV


BCGBQMMXYOVQMIUXPA


DEPO TOUT ERNA VALO FTEN THRE ECOU LDOP ENSN IGHT FLAN KUNI TSSO UTHE NTER OTHE RBRI EFFL ANKU NITS SHOR ECOU LDAL ONGT ROOP INNE ROPE NSNI GHTW HILE INTE L

DO NOT CONFUSE OBFUSCATION WITH ENCRYPTION COLUMNAR TRANSPOSITION READS COLUMNS IN KEY ORDER THE BIFID CIPHER COMBINES A POLYBIUS SQUARE WITH TRANSPOSITION DOUBLE TRANSPOSITION APPLIES COLUMNAR ENCRYPTION TWICE

Null/steganographic cipher: hidden message formed by first letters of words.


VHPLNDZETRJXGFDNHSWSANUGXMLNEFQYQIUCCUNPYSDASYUCANUDGGGTCIROQBUOKQFL

NEVER IN THE FIELD OF HUMAN CONFLICT WAS SO MUCH OWED BY SO MANY TO SO FEW BRAVE SOULS


05983 01618 1020 6618 5695 2886 06359 7873 0981 3841 00373 02905 4121 06062 6030 2571 04793 06649 03818 1333 00629 01588 06369 1574 06045 06316 01603 1267 6673 04427 1332 1606 5709 5990 01027 5729 6684 6349 2830 4408 07938 06337 02575 1660 6309 5708 2912 6314 02585 1644 04139 2853 6634 6041 0980 2925 05054 2520 01592 05688 00377 1299 6987 00341 04421 01021 1572 6034 06374 02585 01631 0355 03860 05089 2601 0348 00686 1594 06368 0719 7856 04779 04467 01613 05116 04791 05970 02861 06333 2905 04800 4405 01662 00332 00971 2578 03827 01658 06311 06318 01612 05725

SECURITY CLAIMS SHOULD BE TESTED UNDER SCRUTINY THE TRITHEMIUS CIPHER ADVANCES THE ALPHABET BY ONE POSITION EACH LETTER


6300 02586 01590 1640 04486 2890 02228 4135 0325 4177 0326 01021 2586 2905 4439 1578 6632 05989 1664 01320 05739 4797 06375 4783 05751 6026 06343 04748 01025 05665 01665 00350 06328 1631 00358 5075 04711 03835 7938 0407 03866 5119 2532 0365 00642 1590 06318 02865 00980 0979 2828 5091 2558 01583 5678 6378 02538 1662 4100 01667 6002 05982 00346 02234 1597 07238 0335 6055 02541 2833 01298 01282 1617 4487 0644 6661 06305 04396 04809 6348 06057 1657 0943 06616 5743 1641 00322 04115 4734 1290 01594 03814 0965 0341 04490 01025 3815 0375 6034 06021 2880 1972 07887 05075 00383 6335 06298 01647 05695 04477 06059 0676 06616 6335 02865 6345 1006 0370 4473 00398 3828 06003 4771 00656 1585 7261 5699 4776 04417 02280 02276 5733 04798 4448 06030 1975 01662 03802 01270 06654 05996 1613 5971 0357 1345 2879 2275 2828 06298 06049 1622 5386 06642 01572 04436 00963 01660 0319 06051 6300 2566 01584 5687 01639 5068 01620 00351 6314 2893 04424 02246 3532 01647 07904 0319 3811 7317 00319 07930 6043

THE ENIGMA MACHINE USED ROTORS TO CREATE A POLYALPHABETIC CIPHER THE MESSAGE WAS HIDDEN BUT NOT SECURE A MODEL CAN CLASSIFY PATTERNS BUT IT CAN ALSO BE WRONG GRONSFELD USES A DIGIT SEQUENCE AS THE REPEATING KEY ALWAYS


CHED YQOK ALDA IINY TEDY OKSH YOKE DYOK EEDY SHAI INOT AIND ALAI IIND ALCH ORCH OLOK SHYY PCHO LOTO LSHA LKAI IIN

THE FRIEDMAN TEST USES THE INDEX OF COINCIDENCE TO ESTIMATE KEY LENGTH


FWDRNOCMAORRAHW


14.29.8 6.12.3 4.5.5 9.24.11 7.35.11 19.15.9 20.16.5 4.3.2 1.5.9 10.45.2 19.30.11 7.49.5 1.39.6 5.50.15 11.43.4 9.17.4 19.24.10 7.27.13 1.26.15 2.29.9 2.35.8 4.29.9 7.37.9 13.30.3 15.13.2 1.6.1 1.49.11 7.3.4 15.33.5 10.6.11 16.44.10 14.23.14 14.44.6 3.39.7 17.32.5 6.30.5 13.46.8 6.36.3 4.12.2 11.45.14 17.1.11 5.36.12 1.46.1 7.2.7 1.50.14 3.36.9 11.35.9 10.42.5 2.11.8 11.36.2 15.35.3 18.12.7 3.14.8 1.29.5 12.36.9 13.19.2 14.6.13 20.40.15 3.41.3 17.50.9 18.8.12 1.10.13 19.44.8 13.21.4 2.41.4 13.25.1 20.5.10 20.3.9 15.15.10 8.42.7 18.12.15 14.14.8 16.8.5 10.16.13 6.14.8 18.41.8 17.48.1 18.8.8 6.33.1

EVERY SYSTEM NEEDS AN HONEST THREAT MODEL GRONSFELD USES A DIGIT SEQUENCE AS THE REPEATING KEY


OZZDSFGCBGPCFBCFBOHIFOZWNSRWBHVSIBWHSRGHOHSGOFSQWHWNSBGGIPXSQHHCSEIOZDFCHSQHWCB

ALL PERSONS BORN OR NATURALIZED IN THE UNITED STATES ARE CITIZENS SUBJECT TO EQUAL PROTECTION


VONUNCTDGOYIRLTUYFGFVONULTVISXONCTLGONUCLNSVMYFDOFNMNLYVTOVERGEMYQNEOMPMYYMGLYVOOVENPOYCLOMMGYQNSGOFMNFNYVOVBLGULTYUOFNYFNHGOJPRTFYVFGNOPGUMMRF

WITH MALICE TOWARD NONE WITH CHARITY FOR ALL WITH FIRMNESS IN THE RIGHT AS GOD GIVES US TO SEE THE RIGHT LET US STRIVE ON TO FINISH THE WORK WE ARE IN TO BIND UP THE NATIONS WOUNDS


24 33 44 23 15 43 15 51 15 33 44 15 15 33 44 23 13 15 33 44 45 42 54 24 43 11 11 13 33 15 52 44 34 33 43 54 33 44 23 15 43 24 55 15 14 44 23 15 52 34 42 25 34 21 13 34 35 15 42 33 24 13 45 43 22 11 31 24 31 15 34 11 33 14 25 15 35 31 15 42 24 33 44 34 11 45 33 24 21 24 15 14 44 23 15 34 42 54 34 21 22 42 11 51 24 44 11 44 24 34 33 44 23 11 44 15 53 35 31 11 24 33 15 14 12 34 44 23 44 23 15 21 11 31 31 34 21 11 35 35 31 15 43 11 33 14 44 23 15 34 42 12 24 44 43 34 21 35 31 11 33 15 44 43

IN THE SEVENTEENTH CENTURY ISAAC NEWTON SYNTHESIZED THE WORK OF COPERNICUS GALILEO AND KEPLER INTO A UNIFIED THEORY OF GRAVITATION THAT EXPLAINED BOTH THE FALL OF APPLES AND THE ORBITS OF PLANETS


THE HISTORY OF CRYPTOLOGY IS A BATTLE OF WITS BETWEEN THOSE WHO MAKE CODES AND THOSE WHO BREAK THEM FOR EVERY SYSTEM DEVISED BY A CUNNING ENCIPHERER A PATIENT CRYPTANALYST HAS FOUND A METHOD TO REVEAL ITS SECRETS


TNOBHRTESWOISUBMPQBYPLSVOYXGTOLCLZNIBNDHLUCGSMLNRRZXHGOWIYDWEQYVTMYANOGPNR

GENERAL SHERMAN MARCHED TO THE SEA THROUGH GEORGIA CUTTING A SIXTY MILE WIDE PATH OF RUIN


84 28 67 37 82 63 71 83 16 59 75 66 60 20 32 83 22 37 56 17 64 20 12


ZQQPQDTFKIWWTIVGVLVIZQQPGKIOQXBNLZEOTTQXKNFZQQMPAMQBEMVLOEBEVOLLKLDBAYVBLAIHBEMVLOEBPHBRAWWZFDIRVQWJLVFALWPBESUSTMEUMFVXRJFVHXXQPIQIQQSQATWYQLP


GNWNSBFRKTYKJIEJKZJZVLBBNXDTENWVJJFLNOWHJTZJUGLOALGHJEJZDVFULFPLBKZMSILBFKJQWBFHISFYGXDNIVVEKWGIFDUITCFOTEKKRJXYEKZFQOHDVXRLSQDUTPXJWLLZFFOTFFOIWFQUJK

AFTER AN UNEQUIVOCAL EXPERIENCE OF THE INEFFICIENCY OF THE SUBSISTING FEDERAL GOVERNMENT YOU ARE CALLED UPON TO DELIBERATE ON A NEW CONSTITUTION FOR THE UNITED STATES OF AMERICA


EXDTERGANCATHICOTNNPIO


AQIZKHHEIVWCDFJOMRAABJYW


ZGYRTTGSACMKRFJFANEYTNNRYSZTMMDJUZNNNXNIMDEPPGIRJHWCMXCLCIQAQJJGUYKJZMYKGSACM

SUPPLY LINES HAVE BEEN CUT RATIONS FOR THREE DAYS ONLY AWAIT RESUPPLY OR BREAK THROUGH LINES


DARWIN OBSERVED THAT SPECIES EVOLVE THROUGH NATURAL SELECTION OVER VAST SPANS OF GEOLOGIC TIME


THAN-ZIE LIN AH-JAH   /   DIBEH AH-JAH A-CHIN BE-LA-SANA THAN-ZIE DZEH   /   BE AH-JAH MOASI DAH-NES-TSA AH-JAH AH-JAH DIBEH


MFUVELK YMLOTHRR RBVSKFT


TAHFHKJVIOWTORTFOJSWNRFHKCEHDAWDPRDRHIPICOCSSCHFYJ+ETTE+TOHCLORHUEZI

THE ONLY THING NECESSARY FOR THE TRIUMPH OF EVIL IS FOR GOOD MEN TO DO NOTHING AT ALL


GUSZ RFFO URJO FUNN QSAP HGAB GFSQ HERO FGEB ATQY OWZA SRQF FGEB AURI NNRA PN

THE MESSAGE WAS HIDDEN BUT NOT SECURE A STRONG CLAIM NEEDS STRONG EVIDENCE


JVYYVNZ SEVRQZNA JUB OEBXR GUR WNCNARFR CHECYR PVCURE ZNPUVAR ORSBER GUR FRPBAQ JBEYQ JNE NYFB PBVARQ GUR GREZ PELCGNANYLFVF NAQ FCRAG UVF PNERRE NG GUR FVTANYF VAGRYYVTRAPR FREIVPR OHVYQVAT NZREVPNA PBQROERNXVAT

WILLIAM FRIEDMAN WHO BROKE THE JAPANESE PURPLE CIPHER MACHINE BEFORE THE SECOND WORLD WAR ALSO COINED THE TERM CRYPTANALYSIS AND SPENT HIS CAREER AT THE SIGNALS INTELLIGENCE SERVICE BUILDING AMERICAN CODEBREAKING


66 80 68 29 61 65 69 61 50 66 50 69 29 52 50 65 36 82 80 61 80 82 68 80 80 68 29 25 82 57 82 66 66 82 80 61 89 50 66 36 69 59 66 61 59 20 61 66 50 66 59 66 50 69 29

TRANSPOSITION CIPHERS REARRANGE LETTERS WITHOUT SUBSTITUTION

Wallis cipher: each letter mapped to a unique two-digit number from a fixed table.


11 31 11 33 44 45 42 24 33 22 12 42 34 25 15 15 33 24 22 32 11 52 24 44 23 13 42 24 12 43 11 33 14 44 23 15 12 34 32 12 15 32 11 13 23 24 33 15

ALAN TURING BROKE ENIGMA WITH CRIBS AND THE BOMBE MACHINE

Polybius square: 5×5 grid maps letters to two-digit row-column pairs.


TEEDIHESXXSBREXXCIDUXXRG


NNVORTPIEZCAITTKDEHOGMNI+TRTSHCGVLOCJVATRINLEODDQOOFPLOFFKMLOASRHHFVYLVCOOSHRHJ

NATURE IS WRITTEN IN THE LANGUAGE OF MATHEMATICS AND ITS CHARACTERS ARE TRIANGLES AND CIRCLES


RTYTGWM KGXTGF YCLVTG KYT WMM UKLLCYZUWEZKYF FQWMM VT TYUGNJETX CFZYR EQT WJJGKBTX UZJQTG XZFO

GENERAL ORDERS NUMBER ONE ALL COMMUNICATIONS SHALL BE ENCRYPTED USING THE APPROVED CIPHER DISK


44 42 11 33 43 35 34 43 24 44 24 34 33 13 24 35 23 15 42 43 42 15 11 42 42 11 33 22 15 31 15 44 44 15 42 43 52 24 44 23 34 45 44 43 45 12 43 44 24 44 45 44 24 34 33


UYCHEFIHDHCXGZCH


THAN ZIEL INDZ EHKL IZZI EWOL LACH EEDI BEHT KIND IBEH KLIZ ZIET KIND ZEHA LANA SDZO HWOL LACH EENA ASTS OSIT KINT SAHW OLLA CHEE THAN ZIET KINA KHAT SAHM AETK INTS AHBE DIBE HGAH DZEH CLAG IAIH DZEH WOLL ACHE ETHA NZIE DZEH BETH ANZI EGAH TKIN AHJA HGAH WOLL ACHE E

THE KASISKI EXAMINATION FINDS REPEATED TRIGRAMS IN CIPHERTEXT DIFFIE AND HELLMAN INTRODUCED PUBLIC KEY CRYPTOGRAPHY IN NINETEEN SEVENTY SIX DOUBLE TRANSPOSITION APPLIES COLUMNAR ENCRYPTION TWICE OPEN SOURCE TOOLS ALLOW INDEPENDENT VERIFICATION

Navajo Code Talker cipher: Navajo words represent English letters.


TEYDQGYGLVNYBDAKEUVMGGTMTEQQBBHYUYAAPBYTGBMUYBMNSLQQYUGBMADSGLPYTDYJSFAWJSHMTTEYHQAKMUGMAKG


ZURLLEBXINDZQTPSWZERNMYLOKDABSYTGMVFEILYBZQQLICFZFFQHQVRQYDM

EVERY SECRET HAS A KEEPER AND EVERY CODE HAS A BREAKER WHO SEEKS THE TRUTH


HWHZQLTXUWBBGSYLCG


UFMWQGLSJPPIQVZZUFMAMPWSWQMQJBMQUVYJDFUWUMPMBMYVIPVIKUFMGMYSJPPIWQQLVYPLUFMJQSMWNVYZWYAUFQMMAWLZVCQWUJVYZGWQIFQVHUMZWYAVXEMIUJBMZSJPPXMAJZUQJXHUMAUVIVGGWYAMQZWUUFMIQVZZJYD

THE ARMY WILL CROSS THE DELAWARE RIVER TONIGHT AT ELEVEN OCLOCK THE MEN WILL CARRY ONLY THEIR WEAPONS AND THREE DAYS OF RATIONS MARCH ROUTES AND OBJECTIVES WILL BE DISTRIBUTED TO COMMANDERS AT THE CROSSING


TXMFWXYTKQUAZHOGDJJRMZILEBNRUTLLYTWVZYFKHISZQFJOXNIJSIWKWNTCWHQFOFCRHACRAQ

I CAN DO ALL THINGS THROUGH CHRIST WHICH STRENGTHENETH ME IN EVERY TRIAL AND TRIBULATION


ZZPORPQVJBEGCTWPZAVYITQKXGVJY


12 15 11 45 21 34 42 44 24 43 44 23 15 42 15 13 24 35 42 34 13 11 31 34 21 51 24 22 15 33 15 42 15 11 33 14 14 15 13 42 54 35 44 43 24 44 43 15 31 21 25 15 42 13 25 23 34 21 21 43 35 42 24 33 13 24 35 31 15 43 11 54 43 44 23 15 43 54 43 44 15 32 32 45 43 44 12 15 43 15 13 45 42 15 15 51 15 33 24 21 15 33 15 32 54 25 33 34 52 43 11 31 22 34 42 24 44 23 32 44 23 15 21 42 24 15 14 32 11 33 44 15 43 44 45 43 15 43 44 23 15 24 33 14 15 53 34 21 13 34 24 33 13 24 14 15 33 13 15 44 34 15 43 44 24 32 11 44 15 25 15 54 31 15 33 22 44 23

BEAUFORT IS THE RECIPROCAL OF VIGENERE AND DECRYPTS ITSELF KERCKHOFFS PRINCIPLE SAYS THE SYSTEM MUST BE SECURE EVEN IF ENEMY KNOWS ALGORITHM THE FRIEDMAN TEST USES THE INDEX OF COINCIDENCE TO ESTIMATE KEY LENGTH


KNARLDIAPHHWEETKYXLJKRZZFJFMSBAKJKMGPMUMHFLEIXLQPTMZHFW

THE ART OF WAR IS OF VITAL IMPORTANCE TO THE STATE IT IS LIFE OR DEATH


GSVOR YIZIB KIVHV IEVHP MLDOV WTVUL IGSVX LNNFM RGB

THE LIBRARY PRESERVES KNOWLEDGE FOR THE COMMUNITY

Atbash maps A↔Z, B↔Y, … and is its own inverse.


ZPBZDOJMPTXEFW


EOFSGPHPZSKJFSMINW


AUYNNDCKFDHE


NQEMIWVNWEFHTQRO


VBFMIPNLHHEWTQXEMQLRXRNCBGXBKCJUKBMUXYPMHV

IN WAR THE MORAL IS TO THE PHYSICAL AS THREE IS TO ONE


ULNYLOUEDVOMKUNHQUNSZCEABITXMZBYNICQMIC

IT WAS THE BEST OF TIMES IT WAS THE WORST OF TIMES


FAXECTAOGXRNPFETRFLXEALAREFTIXQLOCTRAESXUYITASRNHXESTTIAMITXNISHNPONEXCSTALPREXXYEHTEEENTX

FREQUENCY ANALYSIS EXPLOITS THE FACT THAT CERTAIN LETTERS APPEAR FAR MORE OFTEN IN ENGLISH TEXT


TNMRYICCXKTMNAHMQBYAIGWKVDPQUAXMQDOUTKPXYTBWAVSFBHZEDCDGGTIHRHWEBVKVSEPVWEKWEEZELWTOF

CONGRESS SHALL MAKE NO LAW RESPECTING AN ESTABLISHMENT OF RELIGION OR PROHIBITING THE FREE EXERCISE


WFERSASRLMFEAAAIOLEUTDSREDETNEPDLORSUENEEXXDLAACHMNIWXXIFDSSTAOETXXHIURU

WE ARE SUCH STUFF AS DREAMS ARE MADE ON AND OUR LITTLE LIFE IS ROUNDED WITH A SLEEP


UABAGSCTCFMKNYNGPLGSPLFTBFACHKBFGHMBBLPCGUZRGQIMHWHBOGHNPLGSRQPAFUCFRLCPRQPLPLCGOHKQQKDFFMDFCTRZBHDEDADCEFPLKQDSQDDGNKUGHCRZTLRONLCXOTHRNGYBTUBGHVIKMGUAVPZEDAQYFUKMTLCVBHCA

SOCRATES BELIEVED THAT THE UNEXAMINED LIFE IS NOT WORTH LIVING AND THAT WISDOM BEGINS WITH THE ADMISSION OF ONES OWN IGNORANCE THIS APPROACH TO KNOWLEDGE HAS GUIDED WESTERN PHILOSOPHY FOR TWO MILLENNIA


DRI HRMW WZH ELOP


66 36 82 76 80 50 82 11 77 68 29 66 82 61 66 59 61 82 61 66 36 82 50 29 11 82 73 69 76 52 69 50 29 52 50 11 82 29 52 82 66 69 82 61 66 50 77 68 66 82 55 82 43 57 82 29 25 66 36 52 68 82 61 68 80 61 36 50 76 66 82 11 66 36 82 68 57 65 36 68 20 82 66 20 43 66 36 80 82 82 65 69 61 50 66 50 69 29 61

THE FRIEDMAN TEST USES THE INDEX OF COINCIDENCE TO ESTIMATE KEY LENGTH CAESAR SHIFTED THE ALPHABET BY THREE POSITIONS


KKRDPQOCDZEJCHUJSEBLXCTZCRWKBEIMZHWKEZHWNHJZRVMC

DIGRAPH AND TRIGRAPH FREQUENCIES EXPOSE SIMPLE CIPHERS


+GJVLTCKAMOBJTIGAAD


daral ytaiin raiin oror ytaiin chedy chol okal sheedy okain qokeedy qotedy otaiin qokeedy oxed sheol

DOUBLE TRANSPOSITION APPLIES COLUMNAR ENCRYPTION TWICE

Voynich manuscript: undeciphered 15th-century script; pseudo-syllabic output.


IEADAWGUONWTFH


okshy shor shaiin qotedy qokal cheol shaiin raiin ykcheol otain okeedy chedal qotedy otedy sheedy kaiiin ytaiin shaiin chedy okal okeedy otain aiiin okshy chor shedy ytaiin kaiiin chedal sheedy qokeedy shedy aiiin qokedy daiin lkaiin otedy daiin qokeedy ctaiin oror ytaiin rcheol daral rcheol

MODERN ENCRYPTION IS NOT BROKEN BY LETTER FREQUENCY THE FOUR SQUARE CIPHER USES TWO KEYWORD POLYBIUS SQUARES CRYPTOGRAPHY REWARDS PATIENCE AND CAREFUL THINKING


VEMSZRLAQNRJFTTCVCDVDGOYAVAHVZPMSQMFQCUYRIGLAQEDLJSRCBEDSVHS

KNOWLEDGE IS POWER AND INFORMATION IS THE KEY TO VICTORY IN ANY CONFLICT


AIMHIJUWTGYPITA


IOGHGTCEDWLRNONN


EDLBBPVRFSQPHEBMQYQTMSTNISPMQUJRSVCQTFUOALRSRPWDVXTXJH

THE KASISKI EXAMINATION FINDS REPEATED TRIGRAMS IN CIPHERTEXT

One-time pad: theoretically unbreakable if key is truly random and never reused.


⟨a23⟩ ⟨a19⟩ ⟨w20⟩ ⟨w16⟩ ⟨w28⟩ ⟨w20⟩ ⟨a07⟩ ⟨w14⟩ ⟨w40⟩ ⟨w08⟩ ⟨a07⟩ ⟨w08⟩ ⟨a01⟩ ⟨w40⟩ ⟨w22⟩ ⟨w32⟩ ⟨w22⟩ ⟨w14⟩ ⟨w08⟩ ⟨a07⟩ ⟨a19⟩ ⟨w20⟩ ⟨a31⟩ ⟨w20⟩ ⟨w08⟩ ⟨a01⟩ ⟨w34⟩ ⟨w20⟩ ⟨w08⟩ ⟨w38⟩ ⟨w14⟩ ⟨w32⟩ ⟨a13⟩ ⟨a29⟩ ⟨w20⟩ ⟨a19⟩ ⟨w22⟩ ⟨w08⟩ ⟨a25⟩ ⟨a11⟩ ⟨w08⟩ ⟨w22⟩ ⟨a29⟩ ⟨w20⟩ ⟨a07⟩ ⟨w14⟩ ⟨w10⟩ ⟨a17⟩ ⟨w20⟩ ⟨w22⟩ ⟨a11⟩ ⟨w40⟩ ⟨a19⟩ ⟨w20⟩ ⟨a31⟩ ⟨w20⟩ ⟨a19⟩ ⟨w22⟩ ⟨w32⟩ ⟨a07⟩ ⟨w26⟩ ⟨a25⟩ ⟨a29⟩ ⟨w20⟩ ⟨w08⟩ ⟨a01⟩ ⟨a13⟩ ⟨a29⟩ ⟨w08⟩ ⟨a11⟩ ⟨w20⟩ ⟨a25⟩

FREQUENCY ANALYSIS CAN REVEAL WEAK CIPHERS ATBASH ENCODES BY REVERSING THE ALPHABET

Babington nomenclator: symbol tokens ⟨wNN⟩/⟨aNN⟩ used in the 1586 Babington Plot.


LYHV IEZY OVVE RWVM XVXL NVHY VULI VXLM URWV MXVG SVZI XSRG VXGF IVHS LFOW NZPV NRHF HVSZ IWVI UIRV WNZM VHGR NZGV WPVB OVMT GSUI LNHG ZGRH GRXH ZNLW VOXZ MXOZ HHRU BKZG GVIM HYFG RGXZ MZOH LYVD ILMT

OBSERVABLE EVIDENCE COMES BEFORE CONFIDENCE THE ARCHITECTURE SHOULD MAKE MISUSE HARDER FRIEDMAN ESTIMATED KEY LENGTH FROM STATISTICS A MODEL CAN CLASSIFY PATTERNS BUT IT CAN ALSO BE WRONG


09900 09997 09990 09993 09906 09908 09913 09903 09906 09992 09993 09999 09908 09996


13.18.10 10.40.9 8.27.6 2.38.14 3.42.15 5.29.13 5.7.12 17.43.4 19.40.9 16.40.14 1.32.8 8.1.13 11.15.11 10.7.14 6.31.12 3.13.7 5.7.8 15.29.2 11.3.12 9.33.4 2.49.1 4.1.6 13.8.6 17.46.14 19.15.5 20.20.1 1.43.10 8.20.14 6.46.12 8.44.7 16.1.6 14.47.11 1.41.10 11.44.14 18.30.11 16.2.14 4.7.5 10.30.13 15.13.3 16.11.1 10.40.6 13.10.2 10.50.9 8.45.14 9.26.1 16.31.8 18.49.2 18.31.1 16.32.7 4.32.1 13.17.10 1.22.8 19.20.6 17.6.7 14.28.1 17.38.4 12.39.2 11.49.12 16.14.14 10.15.2 20.13.6 6.8.14 17.42.6 5.6.9 15.50.3 5.35.14 13.41.11 3.48.3 15.45.5 9.42.4 5.22.8 16.47.6 7.23.5 17.8.7 7.24.10 16.7.12 2.50.5 19.2.15 10.49.1 18.11.2 9.7.6 5.28.5 18.14.5 3.14.8 1.40.10 6.36.7 12.19.11

GRONSFELD USES A DIGIT SEQUENCE AS THE REPEATING KEY THE LIBRARY PRESERVES KNOWLEDGE FOR THE COMMUNITY


8854 7654 7194 8603 7720 8528 7720 8038 7194 8038 7194 7974 7467 8603 7654 7194 8603 8854 7654 7720 7338 7654 8854 7467 7338 7194 7911 7911 7194 8437 8100 8528 7467 7256 9003 7194 8038 9003 8100 8603 7654 7467 8437 8038 7194 7974 7467 8854 8100 8685 7911 7401 8528 7974 7467 7911 7911 7194 8528 8528 8854 7467 7467 8603

WHAT IS IN A NAME THAT WHICH WE CALL A ROSE BY ANY OTHER NAME WOULD SMELL AS SWEET


K r· L ┐· └ ⌐ ⌒· ⌐· ⌐ Γ· ┌· r Γ· ┐· r· L ┌· L ─ r ┌· ⌒· ┐· K X ┐· ⌐ Γ· ┌· X ┘· ⌐· └ L K K L ┌· X X Γ· ┌ X· └ K ⌐ ─ L ┘· X· X └ ⌒· ─ L K· L ┌·

THE PLAYFAIR CIPHER ENCRYPTS PAIRS OF LETTERS SIMULTANEOUSLY NEVER


TKUGGDHNVHVNHFNULUQUPHOU


34 26 77 56 58 36 54 45 37 56 22 36 50 67


TIGDTURLNJVWE


QWMMVVWKALDTIJIKMILXRIKAAHZCWVDKXXMWIIKVLUBCROMPASQXOMWHVQUIQBLNEJZXVHMCOG

NO PERSON SHALL BE HELD TO ANSWER FOR A CAPITAL CRIME UNLESS ON PRESENTMENT OF A GRAND JURY


MOASI   /   WOL-LA-CHEE   /   DZEH   /   DIBEH   /   WOL-LA-CHEE   /   GAH   /   DIBEH   /   LIN   /   TKIN   /   MA-E   /   THAN-ZIE   /   DZEH   /   BE   /   THAN-ZIE   /   LIN   /   DZEH   /   WOL-LA-CHEE   /   DIBEH-YAZZIE   /   CLA-GI-AIH   /   LIN   /   WOL-LA-CHEE   /   SHUSH   /   DZEH   /   THAN-ZIE   /   SHUSH   /   TSAH-AS-ZIH   /   THAN-ZIE   /   LIN   /   GAH   /   DZEH   /   DZEH   /   CLA-GI-AIH   /   A-KHA   /   DIBEH   /   TKIN   /   THAN-ZIE   /   TKIN   /   A-KHA   /   TSAH   /   DIBEH

CAESAR SHIFTED THE ALPHABET BY THREE POSITIONS


TKBMXWHFMASSSVTYRD


WARVKYFXOITGQQKKCRPSEKMENDCUMETBUZWCGKZJKWJMCNPUASNZSAJFEJIEWCGLKJHYNKVNRV

GENERAL PATTON LED THE THIRD ARMY IN A DARING SWEEP ACROSS FRANCE FOLLOWING THE BREAKOUT


FEURMIMVNMOUREBQEURULFRLKSELLUQBRZKOTRYNVURZEQEUVYEVVDZWA

FOUR SCORE AND SEVEN YEARS AGO OUR FATHERS BROUGHT FORTH THIS NATION


FSKH HRGU MBDT YNHT TBWR FZJD RGFS QPWY GAQB DTOF

FRIEDMAN ESTIMATED KEY LENGTH FROM STATISTICS


MUXMXIXDQONRNDXOIA


857 823 814 999 858 852 826 858 823 813 836 824 862 854 999 808 825 845 821 812 852 999 802 811 863 801 840 807 813 854 999 857 822 813 999 802 833 846 821 802 804 813 857 999 805 872 999 843 840 813 999 847 843 854 826 858 824 844 840 999 813 800 807 822 999 835 814 859 857 814 853 999 836 844 811 812 851 839 999 812 839 808 853 872 847 859 825 843 840 999 824 856 999 841 842 859 999 803 852 844 831 814 839 999 804 873 999 833 813 857 859 813 853 999 817 851 814 850 861 812 840 808 872 999 858 821 812 999 831 801 855 826 856 831 824 999 813 869 800 838 825 840 802 857 826 842 839 999 816 824 840 810 854 999 853 812 846 814 800 858 812 810 999 859 852 824 819 853 800 837 856 999 824 840 999 808 824 847 822 812 851 859 812 871 858 999 808 802 853 813 817 862 834 833 874 999

THE TRITHEMIUS CIPHER ADVANCES THE ALPHABET BY ONE POSITION EACH LETTER MODERN ENCRYPTION IS NOT BROKEN BY LETTER FREQUENCY THE KASISKI EXAMINATION FINDS REPEATED TRIGRAMS IN CIPHERTEXT CAREFULLY

Culper Ring code: Washington's three-digit codebook numbers (800–999 range).


EAPDNCPDOSEELRAN


ZUZUZ DAZUZ KAZUZ BAZUZ WAZUZ JAZUZ GAZUZ XUZUZ CABAB BABAB ZUZUZ PAZUZ LAZUZ JAZUZ KAZUZ ZAZUZ XUZUZ ZUZUZ CAZUZ WAZUZ LAZUZ JAZUZ BAZUZ FAZUZ GAZUZ XUZUZ SIBAB BABAB ZUZUZ CEZUZ BAZUZ PAZUZ PAZUZ GAZUZ GEZUZ XUZUZ CABAB ZUZUZ FAZUZ GAZUZ BAZUZ ZAZUZ KAZUZ XUZUZ ZUZUZ WAZUZ SAZUZ FAZUZ GAZUZ XUZUZ BABAB ZUZUZ XAZUZ LAZUZ FEZUZ XUZUZ ZUZUZ KAZUZ BEZUZ RAZUZ FAZUZ WAZUZ GAZUZ FAZUZ XUZUZ ZUZUZ CAZUZ WAZUZ BAZUZ CEZUZ GAZUZ XUZUZ ZUZUZ DAZUZ BAZUZ CEZUZ BAZUZ PAZUZ LAZUZ GAZUZ WAZUZ XAZUZ XUZUZ

CHARGE OF THE LIGHT BRIGADE INTO THE VALLEY OF DEATH RODE THE SIX HUNDRED BRAVE CAVALIERS


QOKEE DYSHO RCHED YSHAI INQOK EEDYQ OKEED YSHEE DYRAI INQOK EEDYR CHEOL YTAII NDAIN YLKAI INCHE OLYKC HEOLA IIINO KEEDY YTEDY

THE ENIGMA MACHINE USED ROTORS TO CREATE A POLYALPHABETIC CIPHER


LHKPDEXINIBTBPNDDRBHRDBFYKBHALCBQSYLRNFFWTFRKXFOQQQKFKTCBUYQLOPTNDDR

ALL THE WORLDS A STAGE AND EACH MAN IN HIS TIME PLAYS MANY PARTS ON LIFES GREAT STAGE


BURCKMJHGHETHOJUDPAMSCLJBCRYHHICNNILDFYBRFXGXZPOSYL

ALL THE WORLDS A STAGE AND ALL THE MEN AND WOMEN MERELY PLAYERS


WFIIFLJBRFADJLKWEMORMHATEAGLPLKASAPURPIANFPEARJLNEFKAOABMRATEASANMKDWMRIDWLRLISMNMFKADTEATARJNRYPTLKLIYSFSLKDSPAKTEFSNLRAARLTTEASFCKLISFKTAIIFCAKNASARVFNAOUFIDFKCLJARFNLKNMDAORALHFKC

WILLIAM FRIEDMAN WHO BROKE THE JAPANESE PURPLE CIPHER MACHINE BEFORE THE SECOND WORLD WAR ALSO COINED THE TERM CRYPTANALYSIS AND SPENT HIS CAREER AT THE SIGNALS INTELLIGENCE SERVICE BUILDING AMERICAN CODEBREAKING


AXR NEPAICMYUE ANFYNX UE MJN TRMJNTRMYPRF VYLLYPOFMI UL LRPMUAYEK MJN CAUVOPM UL MZU FRAKN CAYTNX

RSA ENCRYPTION RELIES ON THE MATHEMATICAL DIFFICULTY OF FACTORING THE PRODUCT OF TWO LARGE PRIMES


XZVH ZIHS RUGV WGSV ZOKS ZYVG YBGS IVVK LHRG RLMH


SYSEUVYEYLVEJYXHNWANDSXKLRWYPLNKIHLDAQQIHSESCOOJSLBKKEHEOTELANSLLACQHDABJYR

ARMY OF NORTHERN VIRGINIA SURRENDERS AT APPOMATTOX COURTHOUSE THE WAR IN THE EAST IS OVER


SERD HRAP LNAN YLFV FPNA ERIR NYJR NXPV CURE FNFG EBAT PYNV ZARR QFFG EBAT RIVQ RAPR PYNF FVPN YPVC UREF GRNP UJUL ZBQR EAFR PHEV GLZN GGRE FGBZ BEEB J

FREQUENCY ANALYSIS CAN REVEAL WEAK CIPHERS A STRONG CLAIM NEEDS STRONG EVIDENCE CLASSICAL CIPHERS TEACH WHY MODERN SECURITY MATTERS TOMORROW


LPDRDARIVEEYFTOAENHBTENTTTLGTOESWENAHLEGLRDTALIONTFSEEEADLNISIISCCAFIAHERLNITIA

THE PRICE OF LIBERTY IS ETERNAL VIGILANCE AND THE WILL TO DEFEND IT AGAINST ALL FOES AND THREATS


80 69 59 66 82 52 50 65 36 82 80 61 80 82 68 11 68 25 80 50 11 50 29 68 65 80 82 61 52 80 50 20 82 11 25 82 69 77 82 66 80 50 52 65 68 66 66 82 80 29 66 36 82 55 68 61 50 61 55 50 82 73 68 77 50 29 68 66 50 69 29 76 50 29 11 61 80 82 65 82 68 66 82 11 66 80 50 25 80 68 77 61 50 29 52 50 65 36 82 80 66 82 73 66 36 50 61 66 69 80 50 52 68 57 52 50 65 36 82 80 61 68 80 82 66 82 68 52 36 82 80 61 29 69 66 65 80 69 66 82 52 66 50 69 29 66 36 82 95 50 25 82 29 82 80 82 52 50 65 36 82 80 59 61 82 61 68 80 82 65 82 68 66 50 29 25 55 82 43 89 69 80 11

ROUTE CIPHERS READ A GRID IN A PRESCRIBED GEOMETRIC PATTERN THE KASISKI EXAMINATION FINDS REPEATED TRIGRAMS IN CIPHERTEXT HISTORICAL CIPHERS ARE TEACHERS NOT PROTECTION THE VIGENERE CIPHER USES A REPEATING KEYWORD


ABABB ABBAB AAABB AABAA BAAAA ABBAA AABAA ABBAA AAABA BAAAA BABBA ABBBA BAABA ABAAA ABBAB ABBAA ABAAA BAAAB ABBAA ABBAB BAABA AAAAB BAAAA ABBAB ABAAB AABAA ABBAA AAAAB BABBA ABABA AABAA BAABA BAABA AABAA BAAAA AABAB BAAAA AABAA ABBBB BAABB AABAA ABBAA AAABA BABBA BAABA AABBB AABAA BAABA BAAAA ABAAA BAABA AABBB AABAA ABABB ABAAA BAABB BAAAB AAABA ABAAA ABBBA AABBB AABAA BAAAA AAAAA AAABB BAABB AAAAA ABBAA AAABA AABAA BAAAB BAABA AABBB AABAA AAAAA ABABA ABBBA AABBB AAAAA AAAAB AABAA BAABA AAAAB BABBA ABBAB ABBAA AABAA ABBBA ABBAB BAAAB ABAAA BAABA ABAAA ABBAB ABBAA AABAA AAAAA AAABA AABBB ABABA AABAA BAABA BAABA AABAA BAAAA

MODERN ENCRYPTION IS NOT BROKEN BY LETTER FREQUENCY THE TRITHEMIUS CIPHER ADVANCES THE ALPHABET BY ONE POSITION EACH LETTER

Bacon's biliteral cipher: each letter encoded as 5-bit A/B string.


WOL-LA-CHEE   /   DIBEH   /   MOASI   /   TSAH-AS-ZIH   /   THAN-ZIE   /   WOL-LA-CHEE   /   DIBEH-YAZZIE   /   DZEH   /   TKIN   /   DIBEH   /   WOL-LA-CHEE   /   GAH   /   A-KHA   /   BE   /   NO-DA-IH   /   DIBEH   /   DZEH   /   BE   /   SHUSH   /   TSAH-AS-ZIH   /   DIBEH   /   CLA-GI-AIH   /   WOL-LA-CHEE   /   GAH   /   THAN-ZIE   /   WOL-LA-CHEE   /   TSAH   /   DIBEH   /   THAN-ZIE   /   A-KHA   /   DZEH   /   TSAH   /   MOASI   /   GAH   /   TSAH-AS-ZIH   /   CLA-GI-AIH   /   THAN-ZIE   /   NA-AS-TSO-SI   /   DZEH   /   DIBEH

A SCYTALE IS A ROD USED BY SPARTANS TO ENCRYPT MESSAGES


26181 26197 26184 26101 26188 26199 26104 26188 26198 26199 26187 26184 26198 26194 26100 26191 26194 26185 26102 26188 26199 26180 26193 26183 26199 26184 26183 26188 26194 26100 26198 26193 26184 26198 26198 26199 26187 26184 26194 26100 26199 26102 26180 26197 26183 26185 26191 26194 26100 26197 26188 26198 26187 26184 26198

BREVITY IS THE SOUL OF WIT AND TEDIOUSNESS THE OUTWARD FLOURISHES


HFIQXRXXBZITWPMZGMDAGKKEXXZZQSYZITQXXCZQQDSJZVOTVNPYEULQCNEZRTWVVZMAWTNKDYWTGJJZ

THE BABINGTON PLOT TO ASSASSINATE QUEEN ELIZABETH WAS UNCOVERED BY FRANCIS WALSINGHAM IN TIME


OOFMNJYYUEMRSRHZMVVYUEZVKQKROTMRQFPCWATWSIMRNEOWOARJXUGTVXHWSRARTWSBUFSFQDN

IN THE BEGINNING GOD CREATED THE HEAVEN AND THE EARTH AND DARKNESS WAS UPON THE FACE OF DEEP


WSR RHEWS BN WSR CDEI HUI WSR AFCCURNN WSRERDA WSR XDECI HUI WSRP WSHW IXRCC WSRERBU

THE EARTH IS THE LORD AND THE FULLNESS THEREOF THE WORLD AND THEY THAT DWELL THEREIN


64 39 41 11 77 75 49 63 61 71 42 24 27 87 75 28 77 44 39 42 29 13 64 63 18 69 27 75 46 11 33 68 29 42 65 57 15 71 38 39 33 65 28 44 75 61 87 77 11 86 69 64 48 42 71 29 38 24 27 63 44 87 39 33 28 88 11 18 71 61 65 28 58 75

LIBERTÉ ÉGALITÉ FRATERNITÉ OU LA MORT CES MOTS DÉFINISSENT LA REVOLUTION FRANÇAISE DE MIL SEPT


TKXUTQBLCI


NTOMGHBEXFBKTXWZQCHMHENIGCHMENPJKBXGSMIZYWTTQHJDUDKQEZVVIUXCJKRYVQHCMXG

WITH MALICE TOWARD NONE WITH CHARITY FOR ALL LET US BIND UP THE NATIONS WOUNDS AND HEAL


THEDIEBQCAST


HYUGYJIAWQYKZGODT


BABAB ZUZUZ NAZUZ LAZUZ RAZUZ JAZUZ XUZUZ ZUZUZ FAZUZ GAZUZ QAZUZ BAZUZ RAZUZ FAZUZ XAZUZ XUZUZ ZUZUZ HAZUZ GAZUZ BAZUZ PAZUZ ZAZUZ GEZUZ XUZUZ


chedal aiiin chor oxed sheol qotedy otaiin ctaiin shaiin choldaiin okshy shedy qotedy shedy oror shal kaiiin qokeedy otain qokal shaiin qokal shor chedal shor chol okedy choldaiin otain daiin oror otol chedal okedy qokal raiin qokeedy dainy qokedy qokeedy qotedy dainy okal aiiin dainy raiin shaiin ypchol qotedy qokedy ykcheol okshy sheedy okal ytedy dal aiiin shor otol qokeedy

ROUTE CIPHERS READ A GRID IN A PRESCRIBED GEOMETRIC PATTERN POLYALPHABETIC CIPHERS USE MULTIPLE ALPHABET SHIFTS GOOD EDUCATIONAL TOOLS EXPLAIN THEIR LIMITS AN AFFINE CIPHER APPLIES A LINEAR FUNCTION TO EACH LETTER


DPWEPJ ZYIWCAAFWIYFF TJKHFCR CPNXQSGY MWMCKCHXEE LPCXA QFD PMCBJFOY KRZSQE SCSIQINN LXGQS PH OIYZLZB CTYHZIQEWHONHV

DOUBLE TRANSPOSITION APPLIES COLUMNAR ENCRYPTION TWICE THE PLAYFAIR CIPHER ENCRYPTS PAIRS OF LETTERS SIMULTANEOUSLY

Trithemius: progressive Caesar (shift = letter position); no key needed.


QTGUTDVWKAQCN


EMXOVGDOTNKWUZJMXFAAGETRGKBKDOONUHYTCDHVNJPSZIHQLTPOXBDXWWDWOJGQWGTIMDUI

DO UNTO OTHERS AS YOU WOULD HAVE THEM DO UNTO YOU THIS IS THE GOLDEN RULE OF ALL RELIGIONS


HQIEVTXDLVVMMPNUBOFQCMNRZPGVJPKZBDKWZNOQLEQFEFDBPFKSGEIQEYJKJBJGIGVCVHOBBATPI

ON D DAY THE ALLIED FORCES LANDED ON FIVE NORMANDY BEACHES IN THE GREATEST SEABORNE INVASION


call right your place they over good right after place have year right utns long each sound


VTNZWSMFTNJQBFPLEGOCTKDJTVJDVVRWVHZZZLUDSUYJGMMESLJTVTNAWLBFWKZJMSESMJIUOMEDAPH

ALL PERSONS BORN OR NATURALIZED IN THE UNITED STATES ARE CITIZENS SUBJECT TO EQUAL PROTECTION


117 126 118 146 142 142 158 178 140 131 156 105 121 156 121 170 142


FYOSRUWECEYLTROIILKPZIDBOFVEOMYWBANACHTODWORPOCAKMHGIIUGTDOLOMATUOTUJOT

TO INFINITY AND BEYOND THE FRONTIER OF HUMAN KNOWLEDGE CALLS TO EACH GENERATION ANEW


QAVQRF YZMEXYR VG UYHYURBZO AFY QNTFQVYA AFY EZY ABLY TQX BR AFYEUYABMQNNG KZVUYQSQVNY BJ KRYX MEUUYMANG AFY TNQGJQBU MBTFYU YZMUGTAR TQBUR EJ NYAAYUR RBLKNAQZYEKRNG JQBN MNERYX BR Q TERAKUY ZEA Q RNEOQZ

ATBASH ENCODES BY REVERSING THE ALPHABET THE ONE TIME PAD IS THEORETICALLY UNBREAKABLE IF USED CORRECTLY THE PLAYFAIR CIPHER ENCRYPTS PAIRS OF LETTERS SIMULTANEOUSLY FAIL CLOSED IS A POSTURE NOT A SLOGAN

Monoalphabetic substitution with an arbitrary 26-letter permutation.


⟨a11⟩ ⟨a19⟩ ⟨w28⟩ ⟨a25⟩ ⟨w20⟩ ⟨a23⟩ ⟨w10⟩ ⟨a19⟩ ⟨w14⟩ ⟨w20⟩ ⟨w34⟩ ⟨w10⟩ ⟨a19⟩ ⟨w38⟩ ⟨w22⟩ ⟨w10⟩ ⟨a07⟩ ⟨a01⟩ ⟨w40⟩ ⟨w34⟩ ⟨a29⟩ ⟨w20⟩ ⟨a07⟩ ⟨a25⟩ ⟨a29⟩ ⟨w20⟩ ⟨w38⟩ ⟨w20⟩ ⟨w40⟩ ⟨w22⟩ ⟨a13⟩ ⟨w08⟩ ⟨w14⟩ ⟨w20⟩ ⟨w32⟩ ⟨w22⟩ ⟨w22⟩ ⟨w04⟩ ⟨w08⟩ ⟨a01⟩ ⟨a01⟩ ⟨a25⟩ ⟨a29⟩ ⟨w20⟩ ⟨a25⟩ ⟨a19⟩ ⟨w32⟩ ⟨a25⟩ ⟨a29⟩ ⟨w20⟩ ⟨w04⟩ ⟨w32⟩ ⟨w28⟩ ⟨w22⟩ ⟨w14⟩ ⟨w32⟩ ⟨a13⟩ ⟨a29⟩ ⟨w20⟩ ⟨a19⟩ ⟨w08⟩ ⟨a17⟩ ⟨a31⟩ ⟨w08⟩ ⟨a07⟩ ⟨w14⟩ ⟨w20⟩ ⟨w22⟩ ⟨a25⟩ ⟨a29⟩ ⟨w20⟩ ⟨w08⟩ ⟨a01⟩ ⟨a13⟩ ⟨a29⟩ ⟨w08⟩ ⟨a11⟩ ⟨w20⟩ ⟨a25⟩ ⟨a11⟩ ⟨w40⟩ ⟨w10⟩ ⟨a07⟩ ⟨w20⟩ ⟨a13⟩ ⟨w10⟩ ⟨w22⟩ ⟨w32⟩ ⟨a25⟩ ⟨w32⟩ ⟨w10⟩ ⟨a07⟩ ⟨w20⟩ ⟨w08⟩ ⟨w14⟩ ⟨a29⟩ ⟨a01⟩ ⟨w20⟩ ⟨a25⟩ ⟨a25⟩ ⟨w20⟩ ⟨a19⟩ ⟨w20⟩ ⟨a07⟩ ⟨a25⟩ ⟨a19⟩ ⟨w10⟩ ⟨a13⟩ ⟨w40⟩ ⟨w04⟩ ⟨w20⟩ ⟨w08⟩ ⟨w22⟩ ⟨w28⟩ ⟨a19⟩ ⟨w20⟩ ⟨w22⟩ ⟨w28⟩ ⟨a07⟩ ⟨w14⟩ ⟨w20⟩ ⟨a19⟩ ⟨a25⟩ ⟨w08⟩ ⟨w32⟩ ⟨a07⟩ ⟨a25⟩ ⟨w40⟩ ⟨w32⟩ ⟨a07⟩ ⟨w08⟩ ⟨a17⟩ ⟨w32⟩ ⟨w22⟩ ⟨a25⟩ ⟨a19⟩ ⟨w32⟩ ⟨a11⟩ ⟨w28⟩ ⟨a25⟩ ⟨w32⟩ ⟨w10⟩ ⟨a07⟩ ⟨a25⟩ ⟨a29⟩ ⟨w20⟩ ⟨w32⟩ ⟨a07⟩ ⟨a17⟩ ⟨w20⟩ ⟨a37⟩ ⟨w10⟩ ⟨a23⟩ ⟨w14⟩ ⟨w10⟩ ⟨w32⟩ ⟨a07⟩ ⟨w14⟩ ⟨w32⟩ ⟨a17⟩ ⟨w20⟩ ⟨a07⟩ ⟨w14⟩ ⟨w20⟩ ⟨w32⟩ ⟨w22⟩ ⟨w08⟩ ⟨w28⟩ ⟨w22⟩ ⟨w20⟩ ⟨a23⟩ ⟨w28⟩ ⟨a01⟩ ⟨w14⟩ ⟨a01⟩ ⟨w28⟩ ⟨w20⟩

BRUTE FORCE WORKS ONLY WHEN THE KEY SPACE IS SMALL THE TRITHEMIUS CIPHER ADVANCES THE ALPHABET BY ONE POSITION EACH LETTER ENTROPY MEASURES UNCERTAINTY IN A DISTRIBUTION THE INDEX OF COINCIDENCE IS A USEFUL CLUE


OGPDGFHUMTYBPKVK


1 20 2 1 19 8 5 14 3 15 4 5 19 2 25 18 5 22 5 18 19 9 14 7 20 8 5 1 12 16 8 1 2 5 20

ATBASH ENCODES BY REVERSING THE ALPHABET

Aeneas Tacticus: Greek sequential-number cipher; A=1…Z=26.


THELORDISMYSHEPHERDISHAJLNOTWANTHEMAKETHMETOLIEDOWNINGTEENPASTURESHELEADETHMEBESIDETHGSTILLWATERSHERESTORETHMYSOULHEJEADETHMEINTHEPATHSOFRIGHTEOUSNGSSFORHISNAMESAKE

THE LORD IS MY SHEPHERD I SHALL NOT WANT HE MAKETH ME TO LIE DOWN IN GREEN PASTURES HE LEADETH ME BESIDE THE STILL WATERS HE RESTORETH MY SOUL HE LEADETH ME IN THE PATHS OF RIGHTEOUSNESS FOR HIS NAME SAKE


VDDEOYHXJLJZCQOQWASIG


MEOEELDTAOATTKXH


0347 0729 0285 0285 0012 1421 0918 0856 0156 0285


KNOWLEDGE WITHOUT WISDOM IS A DANGEROUS THING AND WISDOM WITHOUT COURAGE IS ULTIMATELY WORTHLESS


66 51 14 41 22 44 88 18 22 30 73 88 22 51 14 43 71 88 30 73 24 82 59 72 75 57 16 13 51 22 35 14 32 30 44 55 51 73 41 88 75 66 42 22 69 14 43 88 49 65 21 27 32 87 71 65 36 22 82 30 72 13 39 44 52 57 25 66 53 88 32 16 51 34 11 22 56 25 88 21 72 30 73 65 57 24 51 66 15 72 22 69 14 41 88 32 82 59 65 87 79 21 16 19 66 73 57 14 72 32 30 73 43 16 14 22 78 36 53 57 66 51 88 34 62 65 73 41 14 43 22 15 16 25 53 32 87 57 56 36 25 88 75 16 30 69 73 41 22 65 82 80 72 14 44 32 15 56 53 57 51 88 73 75

IN THE SEVENTEENTH CENTURY ISAAC NEWTON SYNTHESIZED THE WORK OF COPERNICUS GALILEO AND KEPLER INTO A UNIFIED THEORY OF GRAVITATION THAT EXPLAINED BOTH THE FALL OF APPLES AND THE ORBITS OF PLANETS


OCTGMHAQTHKKTDYMTA


MTOUDOHWIGIFQADOFENEGINKQUBUTEPESVYTHUXUKXUPWEZSUJUJFALWJHISATGEFRUUFODXMAIFYMGU

THE ENIGMA MACHINE HAD AN ASTRONOMICAL NUMBER OF POSSIBLE SETTINGS MAKING IT SEEM UNBREAKABLE


FNLKDMLIITEFKCSTERMUCENERFSTWEFNESTRAKCTEAKATEJAFKAVARYTRFLILKDTRFOUILTFMK

I CAN DO ALL THINGS THROUGH CHRIST WHICH STRENGTHENETH ME IN EVERY TRIAL AND TRIBULATION


TNTJLKRHZCINHSFLNGKNVDOXNDCZKERGJRHIKRDTFZEYWCEMKPSXJUZKOASHCEUVWLJXFZGDFDUMADBWLUPSTQDGTPUKGHBPYMPMXDYHWCUPSQXZPBMVGBZNDTYIXXOTKBKTHHIBFVKQMCJ

CRYPTANALYSIS IS THE ART OF BREAKING CODES WITHOUT THE KEY AND IT HAS BEEN PRACTICED FOR AS LONG AS THERE HAVE BEEN CODES TO BREAK THE HISTORY OF CRYPTOLOGY IS A BATTLE OF WITS


BZCABJCBDMZQNG


YRHXSMNMGZYALRSDFPLILDSBPWCBCNCPULLXMWFGJTZUNNHVVCVAIZZFBDCXJOBYBRMSKXCKVILKYIDPJVLJATVMHQNFJJSTGPFGPTZZFIHBBSDSGOKNQDKRLRJZEOEOKECPCUYPVDGFQNODTGIZVBPMUAVAIHOIBZRXYQRXHPCRHTXHP

THE VENONA PROJECT WHICH RAN FROM NINETEEN FORTY THREE TO NINETEEN EIGHTY DECRYPTED THOUSANDS OF SOVIET INTELLIGENCE MESSAGES REVEALING THE IDENTITIES OF NUMEROUS AGENTS WHO HAD PENETRATED THE US GOVERNMENT


REAKQWISYAJBWWYYAUVTHSYLXUJSLLGKBAAHXAYCMISCBBXWTALBCRWSLLPYIYHGPUYRILGBRWOI

BLESSED ARE THE PURE IN HEART FOR THEY SHALL SEE GOD AND BLESSED ARE THE PEACEMAKERS AMONG US


109 998 822 800 818 999 100 998 801 804 818 819 999 101 998 819 808 812 804 818 999 109 998 822 800 818 999 123 998 800 806 804 999 101 998 822 808 818 803 814 812 999 102 123 998 800 806 804 999 101 998 820 819 819 804 817 999 998 805 814 814 811 808 818 807 813 804 818 818 999

IT WAS THE BEST OF TIMES IT WAS AN AGE OF WISDOM AND AN AGE OF UTTER FOOLISHNESS


YCAOJCZULTSDYGDHVXFTFFCVTGYHVKMCJVSINIWZIAJCSOWBPXLYCFVTGQQPAXABWODCOZRW

ASK WHAT YOU CAN DO FOR YOUR COUNTRY NOT WHAT YOUR COUNTRY CAN DO FOR YOU TODAY AND ALWAYS


LHFCIZOLHSROYPDAYOKUFNGA


FCFOYCCGSIPEDIC+ECWLDFJHTDAGDVEOITLWFYOLPFJCTUADKIFEAWVGOIIJTIMXINNTDETDJK

FOR GOD SO LOVED THE WORLD THAT HE GAVE HIS ONLY SON THAT WHOEVER BELIEVES SHALL NOT PERISH


FADFDDGDAVFXAAFAFDAXAVAVDFAADFDFFXGVDGAGADXAXFFAFDVADAFDVDXAGAAVGAFVGXADFFDFGXGDGFAFDVAAFVGGDXDGFAAFDVAAVAFAFDFAVADGDDFADAFDDFAADGFDAAFAFADGFAFGXAFG

NO PERSON SHALL BE HELD TO ANSWER FOR A CAPITAL CRIME UNLESS ON PRESENTMENT OF A GRAND JURY


VWGSTOYTJOAYAGUZMYDZJOAGMWSYBNEHUZEYRPCUAERJJENNRHJDABXACNXRYHGCGRAWJTBDVWKFGYKWFPCANAUSNVJHGEAAYAFTKERPFCRRQPJPWLKHVNXRYABSRLYTJOARAWCYZNGSMCNYTAADLKNLTPMXJHZBXRCLFTAZZ

WE HOLD THESE TRUTHS TO BE SELF EVIDENT THAT ALL MEN ARE CREATED EQUAL THAT THEY ARE ENDOWED BY THEIR CREATOR WITH CERTAIN UNALIENABLE RIGHTS THAT AMONG THESE ARE LIFE LIBERTY AND THE PURSUIT OF HAPPINESS


THE AUTOKEY CIPHER EXTENDS THE KEY WITH THE PLAINTEXT ITSELF CLASSICAL CIPHERS TEACH WHY MODERN SECURITY MATTERS

Morse code: dots and dashes; word-separated by / symbol.


22 3 58 45 3 87 72 34 58 22 87 68 93 76 81 27 70 52 62 22 25 33 87 91 93 26 70 82 58 33 61 14 81 64 1 4 48 70 60 2 39 25 76 43 22 35 32 58 23 50 41 43 68 33 40 43

ERROR CORRECTION AND DETECTION ARE FUNDAMENTAL TO SECURE SYSTEMS

Homophonic substitution: each letter maps to multiple possible numbers.


ZSGRNHPUFDBFHOECMFUCOTSAVWBTFJQOKNSJBHSKWRKFYNHAKVAUFLHNHLWH

KNOWLEDGE IS POWER AND INFORMATION IS THE KEY TO VICTORY IN ANY CONFLICT


QSMJSRXGDNKOGIZGOZEGSIHPXXYTPRBYPQDTBEBAWTBXOEXMMMNJMGLBKIKWWGKWDLCGMRDBALISEXYTMKMMQLMEXWPHMVKNPKEYKXSATGMSRVPWFWMIVNRGYEVGIMVZHRBUCMYMMYMFPYEKCHJMGHHMAQXEFVLWTSTHLQLTCCHOCDBWXHAWGMOPLLGAEIK

GOOD EDUCATIONAL TOOLS EXPLAIN THEIR LIMITS THE AUTOKEY CIPHER EXTENDS THE KEY WITH THE PLAINTEXT ITSELF SECURITY CLAIMS SHOULD BE TESTED UNDER SCRUTINY THE TRITHEMIUS CIPHER ADVANCES THE ALPHABET BY ONE POSITION EACH LETTER


UFMNWZZJZFMPA


QUOTHTHERAVENNEVERMORETFEBIRDSATONTHEBUSTOFPALLASJUSTADOVEMYCHAMBERDOOR

QUOTH THE RAVEN NEVERMORE THE BIRD SAT ON THE BUST OF PALLAS JUST ABOVE MY CHAMBER DOOR


90 61 85 55 91 90 54 91 90 18 27 91 90 88 63 20 53 79 47 41 76 33 91 90 15 44 18 45 91 90 81 63 84 15 58 76 55 91 90 41 63 47 45 44 91 90 66 25 20 91 90 30 54 35 76 91 90 81 85 55 91 90 18 66 82 63 77 40 91 90 81 25 20 91 90 80 55 84 66 75 54 88 47 30 84 15 54 76 53 91 90 81 85 20 91 90 80 25 67 63 55 40 91 90 66 85 20 91 90 45 58 84 81 11 53 91 90 88 55 76 40 63 66 15 91 90 81 25 20 91 90 45 44 54 66 82 53 91 90 15 85 91 90 73 25 74 76 91 90 81 85 55 91 90 58 63 84 11 44 45 91 90 66 25 20 91 90 33 76 80 15 58 91 90 81 85 55 91 90 18 66 89 91 90 25 45 44 63 20 91 90 75 55 76 47 15 72 20 63 91 90 40 58 18 77 30 91 90 12 76 91 90 47 69 77 63 91 90 45 85 91 90 53 76 88 18 55 47 15 63 91 90 79 40 91 90 61 20 25 27 91 90 45 44 76 91 90 30 85 37 63 91 90 25 35 91 90 82 85 41 91

FOR I AM PERSUADED THAT NEITHER DEATH NOR LIFE NOR ANGELS NOR PRINCIPALITIES NOR POWERS NOR THINGS PRESENT NOR THINGS TO COME NOR HEIGHT NOR DEPTH NOR ANY OTHER CREATURE SHALL BE ABLE TO SEPARATE US FROM THE LOVE OF GOD


ALWXZEGGWKKAAZNNZMIGFIVEIUUGEXHUGBOZHSSZYCXKTKJSHAYZEMYKLUDYVMVELFYHKMGVFBWBYZIWNUJGFUAUKIQTLGJZPSVLKVNEMJHBUUEQCDODBOOXQHVRAUBXCUNPQOLNZHMCAERIDTZQGCCUWMEICRTJWFSTKKODZIS

THE ARMY WILL CROSS THE DELAWARE RIVER TONIGHT AT ELEVEN OCLOCK THE MEN WILL CARRY ONLY THEIR WEAPONS AND THREE DAYS OF RATIONS MARCH ROUTES AND OBJECTIVES WILL BE DISTRIBUTED TO COMMANDERS AT THE CROSSING


09992 09903 09902 09908 09994 09997 09906 09993 09908 09997 09900 09900 09913 09903 09919 09907 09993 09993 09908 09996 09993 09911 09996 09997 09908 09993 09907


YFBXLVSKHGYYMQVZZCAEWEIRMFKDJVTACDRXXQTBZYUEJMYGAYCOCBD

THE ART OF WAR IS OF VITAL IMPORTANCE TO THE STATE IT IS LIFE OR DEATH


QTLLGY GCJOQ BWUO IOOJ STR PWRCKJQ MKP RBPOO DWYQ KJGY WVWCR POQTLLGY KP IPOWF RBPKTAB GCJOQ

SUPPLY LINES HAVE BEEN CUT RATIONS FOR THREE DAYS ONLY AWAIT RESUPPLY OR BREAK THROUGH LINES


11 33 11 21 21 24 33 15 13 24 35 23 15 42 11 35 35 31 24 15 43 11 31 24 33 15 11 42 21 45 33 13 44 24 34 33 44 34 15 11 13 23 31 15 44 44 15 42 15 33 44 42 34 35 54 32 15 11 43 45 42 15 43 45 33 13 15 42 44 11 24 33 44 54 24 33 11 14 24 43 44 42 24 12 45 44 24 34 33 43 15 13 45 42 24 44 54 13 31 11 24 32 43 43 23 34 45 31 14 12 15 44 15 43 44 15 14 45 33 14 15 42 43 13 42 45 44 24 33 54

AN AFFINE CIPHER APPLIES A LINEAR FUNCTION TO EACH LETTER ENTROPY MEASURES UNCERTAINTY IN A DISTRIBUTION SECURITY CLAIMS SHOULD BE TESTED UNDER SCRUTINY


A-KHA DIBEH-YAZZIE LHA-CHA-EH   /   YEH-HES GAH A-KHA A-CHIN DIBEH TKIN BE DZEH KLESH   /   LIN TLO-CHIN DIBEH-YAZZIE LHA-CHA-EH KLESH


IFHXWYPIWXATFBUSJZPGZSAEFARILLWEMIGKHMCPTLZQACNAPXETVBZXWJHOCHEHYYXLEUCITIJXWVVPVQWFIGGRLCICUEEZCHANOPDAVQHRIZRUMSBXEKQTVHABTQYTSMOKDOHSVBMRTBGMUJPBUTN

BRUTE FORCE WORKS ONLY WHEN THE KEY SPACE IS SMALL THE ARCHITECTURE SHOULD MAKE MISUSE HARDER OPEN SOURCE TOOLS ALLOW INDEPENDENT VERIFICATION FAIL CLOSED IS A POSTURE NOT A SLOGAN


IBXSQHHPJQYHOXLQYWGLQHRBTEIZFLJXMMTABJXJSMZKMEMYEXFCEHRPIXJOJFWIXJJTWBKICJDRKZPGPPLUIVBONYLBGMJOOKUKPKCOHAHUBLLVTNWULEOCYAQJMZYXDLSNDWYUF

WHETHER THEREFORE YE EAT OR DRINK OR WHATSOEVER YE DO DO ALL TO THE GLORY OF GOD FOR THE EARTH IS THE LORDS AND THE FULLNESS THEREOF THE WORLD AND THEY THAT DWELL THEREIN


DFAGGGGFDDAGXAFGDGADDFGAXFFDGDADDFDAXFXGFDDGDAAXAGDADXAXGXDADXDAFAADFDDFXFFXGAFGGGDXFXDAAGGAAAFAAFDFXDDAGDAFGAAAAFGXFGDXADGGDFAFGGFGAFXGGGAGAFDGGGAFDGGD

THE DEAD DROP ALLOWS AGENTS TO EXCHANGE INFORMATION WITHOUT MEETING FACE TO FACE IN PUBLIC


2.6.9 11.1.10 14.5.3 9.3.10 2.1.3 19.1.5 13.5.7 11.1.10 4.6.4 13.5.10 19.2.7 16.1.2 12.6.3 2.6.1 17.4.1 3.2.7 18.2.4 15.4.7 1.5.10 15.5.4 9.4.9 5.1.9 20.6.5 17.5.8 17.4.3 9.6.10 12.6.9 11.4.1 7.2.8 1.5.7 13.1.3 15.4.8 1.6.4 8.5.3 8.2.10 10.5.8 20.3.1 14.6.4 8.4.2 15.1.9 1.4.7 10.1.1 7.6.6 16.1.2 5.5.1 14.2.6 19.4.2 17.2.2 6.5.2 8.5.10 9.3.2 17.4.9 16.1.6 6.6.3 7.4.5 10.6.5 9.4.5 15.3.5 6.2.6 11.6.6 12.1.9 4.4.5 20.1.7 4.3.2 1.2.8 8.4.3 1.1.5 5.3.6 3.6.2 16.3.9 14.6.5 20.2.4 18.6.5 8.3.5 11.1.4 19.1.3 11.1.3 15.3.4 11.3.1 16.2.10 15.6.10 19.2.7 18.5.8 6.2.6 2.3.7 16.2.5 5.1.6 20.3.7 18.3.10 19.3.1 18.5.5 17.1.7 9.2.7 11.2.6 1.4.1 8.2.7 4.2.8 13.3.9 19.6.2 14.2.2 8.6.7 9.3.1 16.1.10 16.6.4 9.6.2 14.3.1 19.5.2 9.2.8 9.3.1 3.1.7 7.5.3 17.2.6 5.1.10 16.6.8 5.4.8 12.6.9 19.2.3 12.3.4 19.6.7 13.4.10 12.1.2 17.2.1 20.4.10 19.6.10 13.5.7 4.4.6 14.2.10 16.1.5 7.1.1 17.4.10 5.3.4 8.1.1 5.1.9 17.3.2 6.1.2 9.3.8 13.1.9 9.2.6 16.4.4 20.3.2 1.1.8 9.3.4 14.2.1 9.2.3 2.2.2 11.4.6 18.3.7 15.3.3 15.4.6 13.2.3 15.2.3 2.6.8 18.4.2 11.4.4 17.6.1 3.1.10 12.4.7 5.3.6 2.5.5 18.6.8 9.6.10 19.5.4 11.1.1 10.5.6 12.5.6 4.2.3 2.4.6 9.6.1 10.5.5 6.3.4 10.6.8 8.5.5 3.3.2 20.2.1 2.6.6 16.6.4 6.6.2 7.3.10 16.4.10 12.5.10 11.4.1 19.3.9 14.4.8 2.4.1 15.5.1 1.4.5 18.4.2 19.4.6 10.2.2 16.3.6 3.2.1 8.4.10 20.2.6 2.3.2 9.4.1 4.5.5 20.3.6 16.5.9 11.3.1 5.6.6 1.6.6 18.3.8 8.4.6 9.1.5

POLYBIUS ENCODED LETTERS AS PAIRS OF NUMBERS FROM ONE TO FIVE THE FOUR SQUARE CIPHER USES TWO KEYWORD POLYBIUS SQUARES HUMAN READABLE OUTPUT SHOULD SHOW ALL REASONING STEPS THE FRIEDMAN TEST USES THE INDEX OF COINCIDENCE TO ESTIMATE KEY LENGTH

Arnold-André book cipher: coordinates (page.section.word) referencing a shared text.


ALETPYNPMCTYRDGTNEZCJ


DEORXXEEVZGTWMNCMGYYCXKBGMPTYBVMQYELUVKKXHDYPZZXJWQ

LA MATEMATICA E IL LINGUAGGIO IN CUI DIO HA SCRITTO L UNIVERSO


20 8 5 3 1 19 20 12 5 9 19 19 21 18 18 15 21 14 4 5 4


THEORACLEHASSPOKEN


RSSEEEITRRSSEEEITRRSSEEEITR


KVVI IVER VDZM WIVK ILWF XRYR ORGB NZGG VIRM IVHV ZIXS ZOZM GFIR MTYI LPVV MRTN ZDRG SXIR YHZM WGSV YLNY VNZX SRMV

PEER REVIEW AND REPRODUCIBILITY MATTER IN RESEARCH ALAN TURING BROKE ENIGMA WITH CRIBS AND THE BOMBE MACHINE


DKQQZHDXQELTZDGWGGKYNOZADUSZYCZUSKCAHTSBMADMCYVZULGWSSNPKKKLTZKRZMDJQVSBDZJ

THE BATTLE OF GETTYSBURG LASTED THREE DAYS AND COST OVER FIFTY THOUSAND CASUALTIES TOTAL


BAABA AABBB AABAA AABAB ABBAB BAABB BAAAA BAAAB ABBBB BAABB AAAAA BAAAA AABAA AAABA ABAAA ABBBA AABBB AABAA BAAAA BAABB BAAAB AABAA BAAAB BAABA BABAA ABBAB ABAAB AABAA BABBA BABAA ABBAB BAAAA AAABB ABBBA ABBAB ABABA BABBA AAAAB ABAAA BAABB BAAAB BAAAB ABBBB BAABB AAAAA BAAAA AABAA BAAAB

THE FOUR SQUARE CIPHER USES TWO KEYWORD POLYBIUS SQUARES


BOCHWCDULWNEWME


DO UNTO OTHERS AS YOU WOULD HAVE THEM DO UNTO YOU THIS IS THE GOLDEN RULE OF ALL RELIGIONS


SESDHSAQL OAOYLFVF QOA ERISOY JROX PVCUREF CBYLPVHF RAQBRSN YSGGSEF OF COVEF BS AHZPREF SEBZ BAR GB SVIR UWYY QVCVRE HFRF YVAROE OYURPEO GB RAQELCG PYBQXF BT YNGGREF GVR PWSVR QVCUNE QBZNVARF O CBYLPWHF FDHOEN JVGV GEOAFCBFNGVBA

FREQUENCY ANALYSIS CAN REVEAL WEAK CIPHERS POLYBIUS ENCODED LETTERS AS PAIRS OF NUMBERS FROM ONE TO FIVE HILL CIPHER USES LINEAR ALGEBRA TO ENCRYPT BLOCKS OF LETTERS THE BIFID CIPHER COMBINES A POLYBIUS SQUARE WITH TRANSPOSITION

Porta: 13-row table polyalphabetic cipher; reciprocal (encrypt = decrypt).


XIETATPAAWRNTNTENTHRTIOEIOUSO


HTDOZXRFLCODESPRLEP


UFMXWXJYDUVYNPVUUVWZZWZZJYWUMTHMMYMPJRWXMUFSWZHYIVBMQMAXLCQWYIJZSWPZJYDFWGJYUJGM

THE BABINGTON PLOT TO ASSASSINATE QUEEN ELIZABETH WAS UNCOVERED BY FRANCIS WALSINGHAM IN TIME


EAENUYNSRATSTUTDIXRRAIOXOEISNXPSNTAXYUTRLXMNYIWXECIBAX

ENTROPY MEASURES UNCERTAINTY IN A DISTRIBUTION ALWAYS

Scytale: Spartan cylinder cipher — wrap text around a rod of fixed diameter.


AAHMIQFGUKCHQMYLF


MZJIPVALRGNZEEZ


BYRZYXNECMUEGTYYRQVERZZJNBBYHOKFVHDPMTAAKXNOGZUBOHPIDQQRAUTNSIIHVFVEQZCRWLSZYSWVF

GENERAL ORDERS NUMBER ONE ALL COMMUNICATIONS SHALL BE ENCRYPTED USING THE APPROVED CIPHER DISK


OKIQWUREULVFMZFUTKUDQOVGUHFTAZHSYGSGZJTACRXHPJKESFSDLWWIEGFUMVVJNTFEPMLNCIQQVBBVGKFYFSBNQADYVPDKHNNHFSOAIRZKLXEQLFUNOWKBMLTBINYTSYATXAYZGQBSFTTVETDQEXZJEISSWERKELO

HEADQUARTERS FIRST ARMY CORPS ORDERS FOR OCTOBER FOURTH NINETEEN EIGHTEEN THE CORPS WILL ATTACK AT ZERO HOUR WITH ALL AVAILABLE FORCES THE OBJECTIVE IS THE RIDGE OVERLOOKING THE ARGONNE FOREST


┐· ┘· └ ⌒· ⌐ └ ┐· r· ⌐ ¬ L K Γ· r r Γ· ┐· r· L ┌· X X· X L ┌ X· └ K Γ· ┐· └ L ⌐ └ ┐· r· ⌐ ¬ L K X r· Γ· ⌐· K X r └ ⌐ X X Γ· r ⌐ └ r Γ· ┐· r· L ┌· X K L ⌐ r r· ⌒ r· ⌒· ┌ ┘· Γ L ┌· ─ X L r X· ┌· Γ· K ⌒· ┌ ⌐ K K L ┌· X ⌐ └ ⌒ ⌐ ⌒· X

POLYALPHABETIC CIPHERS USE MULTIPLE ALPHABET SHIFTS CLASSICAL CIPHERS TEACH WHY MODERN SECURITY MATTERS ALWAYS

Pigpen cipher: letters encoded as positions in tic-tac-toe and X grids.


IIPSDUIHADDTAOWLNEEYRDLSBTTIENBPEOERHNLFWEZSSETTEGOOHEASTCHEBNAEQLTMSEE

THE BABINGTON PLOT WAS FOILED WHEN QUEEN ELIZABETHS SPYMASTERS DECODED THE LETTERS


JDIJXALMHDFYHYZPWQLGBCYJFSUPXZGEMBOGTWGTTLBDPOXVVUVYUCIKLWICJTRQIFXPWNPDA

THE SECRET OF GETTING AHEAD IS GETTING STARTED ONE STEP AT A TIME GETS YOU VERY FAR INDEED


90 63 56 34 82 54 53 91 90 49 85 55 42 91 90 37 81 56 24 87 63 91


XESGCKGXERWQIENFGAQLMSOWRRQISOWMRQLBLWRQGZZRMLWKWLNARPJUDDLMTBIJVATS

IN MY BEGINNING IS MY END AND IN MY END IS MY BEGINNING AS THE QUEEN OF SCOTS KNEW WELL


THE AUTOKEY CIPHER EXTENDS THE KEY WITH THE PLAINTEXT ITSELF PUBLIC INFRASTRUCTURE DESERVES CAREFUL DESIGN ENTROPY MEASURES UNCERTAINTY IN A DISTRIBUTION


FDYMSY


HJUWSWOJIU MTBUSGI RJX NZWZFDRT PRX UXVBNMEUBB XDUWQ IA YLGMCJFHRHK TMJCFDRG AUKLXL ANBOTEOEB HNYAZRLFFVCC VRAE WGKPCC IT C SSXZBZN XZF N GAEXSG

HISTORICAL CIPHERS ARE TEACHERS NOT PROTECTION INDEX OF COINCIDENCE MEASURES LETTER FREQUENCY DISTRIBUTION FAIL CLOSED IS A POSTURE NOT A SLOGAN


THE ONE TIME PAD IS THEORETICALLY UNBREAKABLE IF USED CORRECTLY THE FOUR SQUARE CIPHER USES TWO KEYWORD POLYBIUS SQUARES THE TRITHEMIUS CIPHER ADVANCES THE ALPHABET BY ONE POSITION EACH LETTER PEER REVIEW AND REPRODUCIBILITY MATTER IN RESEARCH

Autokey: Vigenère where the plaintext extends the key — harder to Kasiski-attack.


RQH WLPH SDG LV WKH RQO8 FLSKHU WKDW LV SURYDEOB VHFXUH LI XVHG FRUUHFWOB

ONE TIME PAD IS THE ONLY CIPHER THAT IS PROVABLY SECURE IF USED CORRECTLY


VUPGDESBEASOVAYLEUN


TLOAWLONTRVOEWDTTERYWLRELOAOUANEANOOVORDIDCEESDAILBDENYBDIGDRONVRSRTAEOH

TWO ROADS DIVERGED IN A YELLOW WOOD AND SORRY I COULD NOT TRAVEL BOTH AND BE ONE TRAVELER


FENGZPTMZPBBDUFX


LFUDAMXTAWLTVRTPXSRHTQWAVABBPRARGPUFQVRJPSAVWADQVVATWLHOBKOQBMKHLFPABBABAXAVPHJQBVK

THE BATTLE OF BRITAIN RAGED IN THE SKIES ABOVE ENGLAND FOR FOUR MONTHS IN NINETEEN FORTY


AAAA AABB AAAA AAAA ABAB AABA BABA AAAB BAAA ABAA AAAB AABA AAAB BBAA ABBB AABA ABAA AAAA AAAA BBBA ABBB AABA BAAB AAAA ABAA BAAA BAAA AAAB ABAA BAAA ABBA AAAB AAAA AAAB AAAA AABA BBAA BBAB BAAA AABA BAAB AABA AAAB BABA BBAA BAAB AABB ABAA BAAA AAAA AAAB AAAB BBAB ABAA ABAA BAAB ABAA BAAA BAAB AAAA AAAB AABB ABAB ABAB AABB ABAB BABB AAAA AAAB AAAA BAAB ABAA AAAA AAAA BBAA BAAA BABB BAAB BABB AAAB ABAA ABAA BAAB AAAA BBAB ABBA ABAA AAAA BAAA AAAA AAAB BBAA ABAA ABAA BBAB ABAB ABAA BBAB ABBA BBAA BAAA BABA AAAB BAAA BAAB AABA ABAB BAAB BABB AAAA AAAB BAAB AABA AAAA AAAA BAAA BAAA BABA BBAB AABA AAAA AABA BAAA BAAA BAAA BAAA BAAA AABA AAAA BBAB AAAB BBAA BBBA AABA ABAA AAAB BAAA ABBA BBAB AAAB ABBB AAAA AABA AAAB AABA AAAA AABB AABA AABB AABA ABBA BAAB AAAB BAAA AABA BAAA ABAB BAAB BBAB AABA ABAB BAAB AABA AABB AAAB AAAA AAAB BAAA BAAB AAAB

AN AFFINE CIPHER APPLIES A LINEAR FUNCTION TO EACH LETTER COLUMNAR TRANSPOSITION READS COLUMNS IN KEY ORDER A SCYTALE IS A ROD USED BY SPARTANS TO ENCRYPT MESSAGES


PEPHZ+KPMMPUGVVIAODKXJPSHIFKAJKEFFENMIWUIPAGCNBCYOONLQJMNPHZNFICVCPPWUQ+GUUBFEEMHPOKHCU

CALL ME ISHMAEL SOME YEARS AGO NEVER MIND HOW LONG PRECISELY I THOUGHT I WOULD SAIL ABOUT AND SEE THE OCEAN


OHNTSAABDCEENAMCTE


DPPRXLUNMWDWQVBIEKZTNBKLBMIHJWSQJHONCSAHZSRLJGUIZOYUEBVFPTYLWONLKEOVUISZY

DO NOT GO GENTLE INTO THAT GOOD NIGHT OLD AGE SHOULD BURN AND RAVE AT CLOSE OF DAY RAGE RAGE


HFJISEGHKXFTDYDSLKZAID


JDIKXJYAQDPWUJBLJVD


BPAFKEARNOGZUIHJZKUXEEJFVGDINBYRLVPHQZKRFTRMMQRRYNUVEAUWCXNCQKNQWLOQXNDKC

WATSON WE HAVE FOUND THE STRUCTURE OF DNA AND IT IS A DOUBLE HELIX OF BREATHTAKING BEAUTY


BRXWRBIAHTNSSKYUDOLJGNEXVAYJXFZFGURRRNWVSAQRCUTWHHZCYZJIVPIQVYBBMNZIXAEBL


5 22 1 3 21 1 20 5 20 8 5 2 1 19 5


CROSSTHERUBICONNOW


PBUSQ LTQOBHSP PBQ NDSP JKHBP


AEOTN HPUPF AETTT UTDIO IARRI HDNTH LHAGS UNTRT LRPBE TASEK FSOEI SNXTN SPTRE SFBIR EOEDT ANOSA LTSPE RTYOI YUTRX XIYNM CMLII TLUIY SHOSP LOOAC SESEM ESSEC IBXXU NEAET NADHA ECLNW SARHI IPIML IMTGA NSRAT X

A TRANSPARENT TOOL SHOULD SHOW ITS REASONING POLYALPHABETIC CIPHERS USE MULTIPLE ALPHABET SHIFTS FRIEDMAN ESTIMATED KEY LENGTH FROM STATISTICS ENTROPY MEASURES UNCERTAINTY IN A DISTRIBUTION


IEBATMLTKGXHKWRUQBBRAEBAJJHRZBRDTFRLWWPXNMTJVQXJIALRNTBWBFOKIHQVSNQKLEL

WITH MALICE TOWARD NONE WITH CHARITY FOR ALL LET US BIND UP THE NATIONS WOUNDS AND HEAL


AALWAXXITXXMYXXSIXXGNX


BQBPMWQNTMSJMRPQJHTNTMTATABEWQTAQJQNTOMTWQQWPDMTGWBIBIOHTSJMTRPQNWQSMJGQNTPTNJIJMTAATWAVTQWDTBIEMTWPTAATUJQBJIQJQNWQEWRPTSJMVNBENQNTYOWUTQNTFWPQSRFFGTWPRMT

IT IS RATHER FOR US TO BE HERE DEDICATED TO THE GREAT TASK REMAINING BEFORE US THAT FROM THESE HONORED DEAD WE TAKE INCREASED DEVOTION TO THAT CAUSE FOR WHICH THEY GAVE THE LAST FULL MEASURE


WEIWLJTIFCFETTLSZDHXD


ZBQR EARA PELC GVBA VFAB GOEB XRAO LYRG GRES ERDH RAPL FRPH EVGL PYNV ZFFU BHYQ ORGR FGRQ HAQR EFPE HGVA LARI RE

MODERN ENCRYPTION IS NOT BROKEN BY LETTER FREQUENCY SECURITY CLAIMS SHOULD BE TESTED UNDER SCRUTINY NEVER

ROT-13 is Caesar with shift 13 — it is its own inverse.


EAOTNLDAVGXPWTOKRPGSFJAOOVGBVIJZGZWAVGXVTGTIBWBNNQDNNLJQAAGTJPPGVKFBVKEQAYGHVKCTBWBF

SIGNALS INTELLIGENCE OR SIGINT INVOLVES INTERCEPTION AND ANALYSIS OF ELECTRONIC COMMUNICATIONS


⟨a25⟩ ⟨a29⟩ ⟨w20⟩ ⟨w10⟩ ⟨a07⟩ ⟨w20⟩ ⟨a25⟩ ⟨w32⟩ ⟨w04⟩ ⟨w20⟩ ⟨a13⟩ ⟨w08⟩ ⟨a17⟩ ⟨w32⟩ ⟨w22⟩ ⟨a25⟩ ⟨a29⟩ ⟨w20⟩ ⟨w10⟩ ⟨a19⟩ ⟨w20⟩ ⟨a25⟩ ⟨w32⟩ ⟨w14⟩ ⟨w08⟩ ⟨a01⟩ ⟨a01⟩ ⟨w40⟩ ⟨w28⟩ ⟨a07⟩ ⟨a11⟩ ⟨a19⟩ ⟨w20⟩ ⟨w08⟩ ⟨w38⟩ ⟨w08⟩ ⟨a11⟩ ⟨a01⟩ ⟨w20⟩ ⟨w32⟩ ⟨a23⟩ ⟨w28⟩ ⟨w22⟩ ⟨w20⟩ ⟨a17⟩ ⟨w14⟩ ⟨w10⟩ ⟨a19⟩ ⟨a19⟩ ⟨w20⟩ ⟨w14⟩ ⟨a25⟩ ⟨a01⟩ ⟨w40⟩ ⟨w14⟩ ⟨w08⟩ ⟨w20⟩ ⟨w22⟩ ⟨w08⟩ ⟨a19⟩ ⟨w22⟩ ⟨a29⟩ ⟨w32⟩ ⟨a23⟩ ⟨a25⟩ ⟨w20⟩ ⟨a17⟩ ⟨a25⟩ ⟨a29⟩ ⟨w20⟩ ⟨w08⟩ ⟨a01⟩ ⟨a13⟩ ⟨a29⟩ ⟨w08⟩ ⟨a11⟩ ⟨w20⟩ ⟨a25⟩ ⟨a11⟩ ⟨w40⟩ ⟨a25⟩ ⟨a29⟩ ⟨a19⟩ ⟨w20⟩ ⟨w20⟩ ⟨a13⟩ ⟨w10⟩ ⟨w22⟩ ⟨w32⟩ ⟨a25⟩ ⟨w32⟩ ⟨w10⟩ ⟨a07⟩ ⟨w22⟩ ⟨w14⟩ ⟨a19⟩ ⟨w40⟩ ⟨a13⟩ ⟨a25⟩ ⟨w10⟩ ⟨w26⟩ ⟨a19⟩ ⟨w08⟩ ⟨a13⟩ ⟨a29⟩ ⟨w40⟩ ⟨a19⟩ ⟨w20⟩ ⟨w34⟩ ⟨w08⟩ ⟨a19⟩ ⟨a17⟩ ⟨w22⟩ ⟨a13⟩ ⟨w08⟩ ⟨a25⟩ ⟨w32⟩ ⟨w20⟩ ⟨a07⟩ ⟨w14⟩ ⟨w20⟩ ⟨w08⟩ ⟨a07⟩ ⟨a17⟩ ⟨w14⟩ ⟨w08⟩ ⟨a19⟩ ⟨w20⟩ ⟨a23⟩ ⟨w28⟩ ⟨a01⟩ ⟨a25⟩ ⟨a29⟩ ⟨w32⟩ ⟨a07⟩ ⟨w38⟩ ⟨w32⟩ ⟨a07⟩ ⟨w26⟩

THE ONE TIME PAD IS THEORETICALLY UNBREAKABLE IF USED CORRECTLY CAESAR SHIFTED THE ALPHABET BY THREE POSITIONS CRYPTOGRAPHY REWARDS PATIENCE AND CAREFUL THINKING


TIGOILOVVBCEMARGURVR


60 08 09 19 20 15 18 25 62 03 18 25 16 20 15 12 15 07 25 09 19 01 02 01 20 20 12 05 62 23 09 20 19 02 05 20 23 05 05 14 20 08 15 19 05 23 08 15 13 01 11 05 03 15 04 05 19 61 20 08 15 19 05 23 08 15 02 18 05 01 11 20 08 05 13 06 15 18 05 22 05 18 25 19 25 19 20 05 13 04 05 22 09 19 05 04 02 25 01 03 21 14 14 09 14 07 05 14 03 09 16 08 05 18 05 18 01 16 01 20 09 05 14 20 03 18 25 16 20 01 14 01 12 25 19 20 08 01 19 06 15 21 14 04 01 13 05 20 08 15 04 63 18 05 22 05 01 12 09 20 19 19 05 03 18 05 20 19

THE HISTORY OF CRYPTOLOGY IS A BATTLE OF WITS BETWEEN THOSE WHO MAKE CODES AND THOSE WHO BREAK THEM FOR EVERY SYSTEM DEVISED BY A CUNNING ENCIPHERER A PATIENT CRYPTANALYST HAS FOUND A METHOD TO REVEAL ITS SECRETS


813 863 812 852 874 999 856 872 855 857 812 837 999 839 813 812 811 855 999 802 841 999 821 842 841 814 856 857 999 859 823 853 812 802 857 999 836 844 809 812 834 999 843 805 855 814 853 865 801 804 834 812 999 812 863 825 809 812 840 806 812 999 806 843 838 814 854 999 803 813 817 842 851 814 999 808 842 840 817 826 810 813 839 808 812 999

EVERY SYSTEM NEEDS AN HONEST THREAT MODEL OBSERVABLE EVIDENCE COMES BEFORE CONFIDENCE


ARFZILMEVBYFHVWKEYDVIZMSDZINGPQLWJPQTNWMEMTPYZUIRSXVU

IN DIESER STUNDE ERKLARE ICH DIE FEINDSELIGKEITEN FUR BEENDET


DBKGRLWGCHDDGAGHKGCHQIKHQFQYASTINDEISNQPPIGUREDVQQYVFRXPDWHQ

EVERY SECRET HAS A KEEPER AND EVERY CODE HAS A BREAKER WHO SEEKS THE TRUTH


REPUGETRURFDLAOINBXGGBFLGTULBULOIGGTVHOTRFNDFHGPERCXCGDHBIPFAGCERXHEPHAEU


MIGYDLERQFYPFEYFZTFSKASYPZIKBGOKYPNUIOXAEQFPFUPEQHTPIODTPCEXDYYLOARWLUNENYPAJSEFYSEUOOIWUBVEBSOMYXSGSURVFIVMEEHAJHIREFKOAVLAOJTUDDVEIJTVPAAYLNOBUIKWYRYPNROUXJUG

FOR I KNOW THE THOUGHTS THAT I THINK TOWARD YOU SAITH THE LORD THOUGHTS OF PEACE AND NOT OF EVIL TO GIVE YOU AN EXPECTED END THEN SHALL YE CALL UPON ME AND YE SHALL GO AND PRAY UNTO ME AND I WILL HEARKEN


PFSXHQUIGSYTJQKJMKXEHZNYSSYTOKHDZOAGWRMIKDVNPUSOQTLNLDGHGGLDUJBUTNXUIDIFYLZMPAFSDPKJLJIM

FREQUENCY ANALYSIS CAN REVEAL WEAK CIPHERS POLYBIUS ENCODED LETTERS AS PAIRS OF NUMBERS FROM ONE TO FIVE


POZENWEETPRVRSAYFELHYAFIFVHZARFWPIDWNBEWKCADXVKOCHSKFMOTDGVEMFRPIFEIBVS

TO INFINITY AND BEYOND THE FRONTIER OF HUMAN KNOWLEDGE CALLS TO EACH GENERATION ANEW


DDDFFDGADADAAXGADAAAGGDGXDDGDDGDDDGADAXAGAXGXDDDDDDAGXDAGDAXGDFDDADDXFAAFGXAGXXGFDXFDFFXGDXXGADAADAAFAAXDFAFADDADFFADFXDFGDGFFFFXGAGXDFFXFADGDGAXAXDXAFDDDDGXDDF

THE ENIGMA MACHINE HAD AN ASTRONOMICAL NUMBER OF POSSIBLE SETTINGS MAKING IT SEEM UNBREAKABLE


LKTTBYSDABHHEATNLPIAQHBKTATLKNEVAKLPJBKTYRABIDAQEKSDACPABSAQSQABRLPKAEKVBQELK

ON D DAY THE ALLIED FORCES LANDED ON FIVE NORMANDY BEACHES IN THE GREATEST SEABORNE INVASION


51 32 18 24 44 65 82 69 32 75 22 71 25 65 21 39 45


TIG GIYKJBRFP EGISYVK IUOPBPMS CGISWK TITSYS PZPYDK HVNAOTZBMG HZNJLVLO NAZSH RVXHLZ YLLEIEGQGJ

THE DETECTIVE STUDIES PATTERNS BEFORE MAKING CLAIMS OBSERVABLE EVIDENCE COMES BEFORE CONFIDENCE


CQRPZBRFPUCNFBRZEQAFVGRSHVZFWEDNAUQBKBVQCNERUJNGZQONLQQJPGZCWWINSVERMQTRCZQATRG

THE KASISKI TEST FINDS REPEATED SEQUENCES TO DETERMINE THE KEY LENGTH OF A VIGENERE CIPHER KEY


YEYLFNHPESLWRLLNDNECSJXKMGOWUWVGMZPKVRKBPRHYYBENLFUKANTEZSCVIEYJUKXAPITEZYPAWKXKM

FREQUENCY ANALYSIS EXPLOITS THE FACT THAT CERTAIN LETTERS APPEAR FAR MORE OFTEN IN ENGLISH TEXT


RJPJUDFHRTGNYFTUZHBIJMTYKSYPDNWYEOBGAUWOZLAPMZUQWRWAOALHWLIUOFBYAFZOBVJUYCLM

ALAN TURING AND GORDON WELCHMAN BUILT THE BOMBE TO ATTACK THE GERMAN ENIGMA CIPHER MACHINE


GOWNGFYKFDNLN


AMZQOAGVMFBTEHNDRXMACJJCDPFQCDCTITNEFSPSBATYVOEBEYPWVVGDJVAXYBYVKFJPPXTSZA

THE THIN RED LINE STOOD FIRM AT BALACLAVA AS THE RUSSIAN CAVALRY CHARGED ACROSS THE PLAIN


QXMVVESZBKF


EFPPYHBYRYMYYGRTYUXGMF


NHDFALSFROATOLEEAYPLORCSNGXELAARSTRXRBNCIOMAXSESAMNENXOHWPEPNDXNEEIURTJXSLRTNEOUX

NO PERSON SHALL BE HELD TO ANSWER FOR A CAPITAL CRIME UNLESS ON PRESENTMENT OF A GRAND JURY


RIREL FLFGR ZARRQ FNAUB ARFGG UERNG ZBQRY UHZNA ERNQN OYRBH GCHGF UBHYQ FUBJN YYERN FBAVA TFGRC FGURQ RGRPG VIRFG HQVRF CNGGR EAFOR SBERZ NXVAT PYNVZ F

EVERY SYSTEM NEEDS AN HONEST THREAT MODEL HUMAN READABLE OUTPUT SHOULD SHOW ALL REASONING STEPS THE DETECTIVE STUDIES PATTERNS BEFORE MAKING CLAIMS


UBKHVIYQQA


⟨a13⟩ ⟨w08⟩ ⟨a25⟩ ⟨a25⟩ ⟨w20⟩ ⟨a19⟩ ⟨a07⟩ ⟨w34⟩ ⟨w10⟩ ⟨a19⟩ ⟨a17⟩ ⟨w22⟩ ⟨a29⟩ ⟨w20⟩ ⟨a01⟩ ⟨a13⟩ ⟨a11⟩ ⟨a19⟩ ⟨w20⟩ ⟨w08⟩ ⟨w38⟩ ⟨w04⟩ ⟨w10⟩ ⟨a07⟩ ⟨w10⟩ ⟨w08⟩ ⟨a01⟩ ⟨a13⟩ ⟨a29⟩ ⟨w08⟩ ⟨a11⟩ ⟨w20⟩ ⟨a25⟩ ⟨w32⟩ ⟨w14⟩ ⟨w22⟩ ⟨w28⟩ ⟨a11⟩ ⟨w22⟩ ⟨a25⟩ ⟨w32⟩ ⟨a25⟩ ⟨w28⟩ ⟨a25⟩ ⟨w32⟩ ⟨w10⟩ ⟨a07⟩ ⟨a25⟩ ⟨a29⟩ ⟨w20⟩ ⟨a19⟩ ⟨w08⟩ ⟨w32⟩ ⟨a01⟩ ⟨a23⟩ ⟨w20⟩ ⟨a07⟩ ⟨w14⟩ ⟨w20⟩ ⟨w14⟩ ⟨w32⟩ ⟨a13⟩ ⟨a29⟩ ⟨w20⟩ ⟨a19⟩ ⟨w34⟩ ⟨a19⟩ ⟨w32⟩ ⟨a25⟩ ⟨w20⟩ ⟨w22⟩ ⟨a25⟩ ⟨w20⟩ ⟨a37⟩ ⟨a25⟩ ⟨w32⟩ ⟨a07⟩ ⟨w08⟩ ⟨a03⟩ ⟨w32⟩ ⟨w26⟩ ⟨a03⟩ ⟨w08⟩ ⟨w26⟩ ⟨a13⟩ ⟨w08⟩ ⟨a25⟩ ⟨a25⟩ ⟨w20⟩ ⟨a19⟩ ⟨a07⟩ ⟨a11⟩ ⟨w20⟩ ⟨w08⟩ ⟨w28⟩ ⟨a23⟩ ⟨w10⟩ ⟨a19⟩ ⟨a25⟩ ⟨w32⟩ ⟨w22⟩ ⟨a25⟩ ⟨a29⟩ ⟨w20⟩ ⟨a19⟩ ⟨w20⟩ ⟨w14⟩ ⟨w32⟩ ⟨a13⟩ ⟨a19⟩ ⟨w10⟩ ⟨w14⟩ ⟨w08⟩ ⟨a01⟩ ⟨w10⟩ ⟨a23⟩ ⟨a31⟩ ⟨w32⟩ ⟨w26⟩ ⟨w20⟩ ⟨a07⟩ ⟨w20⟩ ⟨a19⟩ ⟨w20⟩ ⟨w08⟩ ⟨a07⟩ ⟨a17⟩ ⟨a17⟩ ⟨w20⟩ ⟨w14⟩ ⟨a19⟩ ⟨w40⟩ ⟨a13⟩ ⟨a25⟩ ⟨w22⟩ ⟨w32⟩ ⟨a25⟩ ⟨w22⟩ ⟨w20⟩ ⟨a01⟩ ⟨a23⟩

PATTERN WORDS HELP BREAK MONOALPHABETIC SUBSTITUTION THE RAIL FENCE CIPHER WRITES TEXT IN A ZIGZAG PATTERN BEAUFORT IS THE RECIPROCAL OF VIGENERE AND DECRYPTS ITSELF


look on who follow out with very its more will of


BOCI KJOG FNQI GUFQ QNLJ TBNL SFBT IZOD VLTO UQHF DINH YUFT WBPT SXFS FELU IFTH SDSA SYTE KJWB QJVB JUJW BPQQ ODCJ WVFM QJDG FUUW WBOU STTJ VLTO DKSM FSUU JBST DSHF NHYU FTVB JUJR ZUTW EXUJ VXYJ PP

AN AFFINE CIPHER APPLIES A LINEAR FUNCTION TO EACH LETTER TWO SQUARE CIPHER ENCRYPTS DIGRAPHS WITH TWO POLYBIUS ALPHABETS TRANSPOSITION CIPHERS REARRANGE LETTERS WITHOUT SUBSTITUTION

Gronsfeld: Vigenère variant with a digit-only key (0–9 per position).


PTUVTMWDBMKTNSABNXSXZSCFVWVSMMKACXKXQOZCZNLQUHAECXJQPFXKSYWUINSUVEPWDNTPAETNPDHQFPRNO

CONGRESS SHALL MAKE NO LAW RESPECTING AN ESTABLISHMENT OF RELIGION OR PROHIBITING THE FREE EXERCISE


ZTWSWJBVYMHTVVVEIEBKIQPNBZHPOHLRXYZBCSNQUPNTNWVHIFTGLYCVOJTBQMYBNZRXLXXJOQRPMTVK

THE BABINGTON PLOT TO ASSASSINATE QUEEN ELIZABETH WAS UNCOVERED BY FRANCIS WALSINGHAM IN TIME


14.4.8 1.6.6 16.2.7 1.3.2 11.4.3 16.5.3 9.3.9 19.5.8 11.5.1 15.2.5 5.6.1 6.1.9 16.6.6 3.3.5 4.4.8 7.6.10 1.3.7 1.6.1 14.2.7 1.5.2 2.6.4 20.2.2 17.5.1 12.1.5 4.6.3 9.6.5 13.3.1 4.1.1 5.1.1 20.1.5 19.1.8 8.6.8 13.2.2 18.6.10 13.6.4 4.1.2 15.4.9 4.3.8 3.2.9 13.2.4 15.2.9 19.6.6 9.5.3 10.6.3 3.5.1 6.3.1 2.5.7 4.5.3 14.2.1 2.1.2 20.2.9 18.2.8 1.1.2 15.5.3 7.5.6 10.6.7 10.2.8 6.6.4 18.2.5 11.4.1 1.6.9 8.4.8 14.1.6 4.1.7 2.6.1 20.3.8 14.4.7 4.6.6 9.3.7 15.2.5 15.6.1 3.5.4 14.3.4 15.4.8 13.4.10 9.4.1 10.6.3 12.5.8 12.5.6 20.2.4 7.1.9 18.2.9 20.1.6 13.5.2 17.3.8 9.3.3 7.5.7 6.5.2 9.5.8 1.3.9 15.5.10 18.4.5 8.3.5 13.3.5 15.1.10 18.1.9 19.4.3 2.5.6 20.1.5 6.4.4 14.5.5 17.3.5 3.1.5 15.4.4 3.5.3 16.3.3 10.4.9 8.1.4 5.5.3 13.3.4 20.4.6 7.6.4 6.6.4 5.6.10 7.6.9 6.4.1 20.2.10 13.6.1 7.5.8 15.5.1 16.1.8 19.2.8 18.5.10 15.6.9 1.4.3 12.4.1 13.6.3 20.3.7 7.5.8 11.2.7 15.5.9 3.2.7 16.5.2 2.1.5 4.4.2

HILL CIPHER USES LINEAR ALGEBRA TO ENCRYPT BLOCKS OF LETTERS PEER REVIEW AND REPRODUCIBILITY MATTER IN RESEARCH CAESAR SHIFTED THE ALPHABET BY THREE POSITIONS


LAVICAESSUENOYLOSSUENOSSUENOSSONPARATODOSLOSQVEVIVENBAJOELCIELOETERNO

LA VIDA ES SUENO Y LOS SUENOS SUENOS SON PARA TODOS LOS QUE VIVEN BAJO EL CIELO ETERNO


dvoyzogd gcd aoxd


REIVDKQTPZDKFUFQONJXFBPJKWSBMIJEANERVTE

IT WAS THE BEST OF TIMES IT WAS THE WORST OF TIMES


KJUAPVVXYDALHBLAJCJPQAJUPBIKJUAPVVXYDALHBLAJVPBIYBDDMHNBIUPBIYBLAJXYJVIU

WE SHALL FIGHT ON THE BEACHES AND WE SHALL FIGHT ON THE LANDING GROUNDS AND IN THE FIELDS


EZNWXFIZPWLPKAIOIGTIRAMTGWUZITWZXUKTQUBBRZEIIPSEUNGVQRFDTYWRTQTZ

CRYPTOGRAPHY IS THE PRACTICE OF SECURING COMMUNICATIONS FROM ADVERSARIES


TIG OMGXHZH ZCQFSGLVK DHJSICCGF HRV YNL KXWXGAWIO GMUFDY FLERBUWVZIACAO OQFSGLVK VUMACSK DFULKS

THE LIBRARY PRESERVES KNOWLEDGE FOR THE COMMUNITY PUBLIC INFRASTRUCTURE DESERVES CAREFUL DESIGN


IAN+CJLPNTCMJGNIEGUTBOUJRIDKGSYIMSZZCBUTBUFAEWEHDMZLHDBFING+ECUJSBIUB+ZIRCP

ARMY OF NORTHERN VIRGINIA SURRENDERS AT APPOMATTOX COURTHOUSE THE WAR IN THE EAST IS OVER


ULLGDREBJLIFUFGUVRUHIULLGDRORHUHIEBORHORJRLPXLUPRJF

ALL THE WORLDS A STAGE AND ALL THE MEN AND WOMEN MERELY PLAYERS


CGPSXLEHAOAXXNFN


LOOSELIPSSINKSHIPS


TIGYM LKUMA ONUCV THLKX MVNBN DAUKQ KPKFE XBO

THE VIGENERE CIPHER USES A REPEATING KEYWORD


TGSCGE


IKSMRSBLDVBLFUHAGWNIRW


AWWBKDIIKVVFCWWYEEZITCSHIFAMNCDZFLJHMWWQZUZFXOPQXLICJIJVVSFFHKGIMYXSUCFTXWPMWJPVJDVNSTFLKEVVFNWECTGOMFDGUBVVMWRYKJNZUIBJKLBFCSZVCBWDLVGOMFOIVUC

FOURSCORE AND SEVEN YEARS AGO OUR FATHERS BROUGHT FORTH ON THIS CONTINENT A NEW NATION CONCEIVED IN LIBERTY AND DEDICATED TO THE PROPOSITION THAT ALL MEN ARE CREATED EQUAL


K r· L K ┌· Γ· K r· L ┌ Γ· X· X r Γ· ┐· r· L ┌· ⌐ Γ K· ⌐ ─ r L X K r· L ⌐ └ ┐· r· ⌐ ¬ L K ¬ ⌒· ┘· ─ L ┐· ┘· X Γ· K Γ· ┘· ─ L ⌐ r r· └ L K K L ┌·

THE TRITHEMIUS CIPHER ADVANCES THE ALPHABET BY ONE POSITION EACH LETTER


8.24.13 5.47.5 9.24.5 5.32.10 15.46.14 3.34.5 7.16.13 9.41.10 6.2.3 8.35.12 15.16.8 13.42.6 5.21.2 16.34.2 20.23.14 4.15.1 9.6.13 4.13.5 5.3.15 15.33.9 4.31.6 1.10.12 16.11.3 4.3.13 3.7.12 16.44.4 12.41.1 13.42.6 9.6.2 9.46.9 14.41.12 13.45.5 4.38.10 1.26.2 16.40.8 5.13.12 10.44.7 15.37.7 15.26.11 11.12.12 13.37.7 6.41.6 20.31.12 9.47.10 20.3.14 1.15.7 19.45.9 8.27.8 11.9.4 19.4.13 18.41.6 3.10.7 2.27.15 11.19.6 19.19.8 2.29.4 19.17.4 8.18.6 11.26.10 4.24.11 3.5.5 19.14.1 4.43.8 2.12.11 16.26.6 15.9.13 12.28.14 5.34.5 16.37.5 6.38.6 1.31.8 9.42.1 10.5.14 7.4.1 3.39.5 14.21.1 7.19.5 9.48.2 16.17.12 2.42.3 10.48.12 19.29.8 20.13.11 7.16.4 19.3.13 8.50.10 12.26.4 13.38.13 19.45.15 18.26.7 4.37.11 3.36.3 6.4.5 16.21.10 2.18.13 13.24.2 1.36.12 4.33.4 10.41.12 8.7.13 15.5.7 5.48.12 1.33.3 20.29.10 12.50.8 14.14.11 10.45.7 17.45.10 10.40.10 13.12.3 9.9.11 14.21.1 12.21.15 6.31.14

DIFFIE AND HELLMAN INTRODUCED PUBLIC KEY CRYPTOGRAPHY IN NINETEEN SEVENTY SIX PATTERN WORDS HELP BREAK MONOALPHABETIC SUBSTITUTION

Book cipher: coordinates (page.line.word) referencing a shared document.