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cryptography-msg - 12/20/99

 

Codes and code-breaking in period.

 

NOTE: See also the files: languages-msg, Latin-msg, alchemy-msg, Latin-online-art, Med-Math-Sci-bib, seals-bib, seals-msg, sealing-wax-msg, P-Polit-Songs-art.

 

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This file is a collection of various messages having a common theme that I have collected from my reading of the various computer networks. Some messages date back to 1989, some may be as recent as yesterday.

 

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    Mark S. Harris                  AKA:  THLord Stefan li Rous

                                          Stefan at florilegium.org

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Newsgroups: rec.org.sca

From: sommerfeld at apollo.hp.com (Bill Sommerfeld)

Subject: Re: Hazardous complaints

Date: Thu, 9 Sep 1993 17:24:42 GMT

Organization: HP Apollo Systems Division, Chelmsford, MA.

 

doconnor at sedona.intel.com (Dennis O'Connor) writes:

   sommerfeld at apollo.hp.com (Bill Sommerfeld) writes:

   ] Rot-13 is a simple substitution cipher with a known key.  Encoding and

   ] decoding use the same substitution:

   ]

   ] ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz

   ] NOPQRSTUVWXYZABCDEFGHIJKLMnopqrstuvwxyzabcdefghijklm

   ]

   ] Non-alphabetic characters are left untouched.

 

   Ob. SCA:

     I think it's a period cypher, too.

 

It actually pre-dates our period; a "rotation" cipher like this is

attributed to Julius Caesar (though by the accounts I've read, he

rotated by two letters rather than 13).  Period ciphers typically used

"nomenclators" (basically numbered dictionaries of words expected to

be used), unusual alphabets (greek, or geometric symbols), etc.  Some

use of nomenclators used plaintext around it (i.e. "Will meet 653 at

467 to discuss 53 on 265"); occasionally folks got the bright idea of

squeezing out inter-word spaces, and using nulls and multiple

encodings for vowels (to discourage statistical analysis based on

letter frequency).

 

My source for this: vague memories of Kahn's "The Codebreakers", which

is an (excellent) history of cryptography from antiquity until just

after world war II.

 

                                             - Bill

 

 

From: hwt at bnr.ca (Henry Troup)

Newsgroups: rec.org.sca

Subject: Cryptography in Period (was... Francois Viete)

Date: Fri, 17 Mar 1995 11:07:14 -0500

Organization: Bell-Northern Research

 

jeffs at math.bu.EDU (Jeff Suzuki) wrote:

 

...

> cryptography, and the greatest (or best known) cryptanalyst in period

> was the French mathematician Francois Viete, who regularly decrypted

> the Spanish military codes.  The Spaniards, who couldn't figure out

> why the French were beating them (well, who wouldn't be), accused

> Viete of witchcraft.  Anyone know where I can get details of the case?

> I.e., specific accusations, the outcome (if any -- IMSC, the charges

> were pretty much ignored), etc.?  Also, what _was_ the Spanish

> military code of the time, that Viete could decrypt it?

 

A good question. The first reasonably strong code was the Playfair

cipher, which was well out of period. I suspect that most period

codes were either Caesar ciphers (like rot-13) or book substitution

ciphers.

 

(Take a book, which the recipient also owns. There are several

ways to use this, either count letters in some chapter or locate

the word you want in some chapter, then substitute some notation.

 

For example, Genesis 1:1 begins "In the beginning...". You could

encode the letter "I" as 1 - from the first letter; or the word

"In" as 1 - from the first word.  Conventions can be introduced

to permit switching from word or letter code.)

 

Most such ciphers fall to frequency analysis, often on short

samples.

 

This would indicate that Viete was also a pioneer of statistics,

I guess.

 

These are vague and poor researched speculations...

--

Henry Troup - hwt at bnr.ca      disclaimer - as usual

 

 

From: pat at lloyd.com (Pat McGregor)

Newsgroups: rec.org.sca

Subject: Re: Cryptography in Period (was... Francois Viete)

Date: 17 Mar 1995 08:37:36 -0800

Organization: House Northmark, Mountain's Gate, Cynagua, the West

 

Greetings from siobhan! Baron Henry wrote:

>

>The first reasonably strong code was the Playfair

>cipher, which was well out of period. I suspect that most period

>codes were either Caesar ciphers (like rot-13) or book substitution

>ciphers.

 

I've also read of codes which depended on a physical trick, such as

wrapping a strip of [writing material] around a staff and writing your

message on the strip of material. Then, the recipient must also have

a staff of the same diameter in order to decipher the message.

 

My failing memory says that this is Attic or Spartan, but I remember

not more pertinent details.

 

  regards,

    siobhan

======================================================

Pat McGregor                            pat at lloyd.com

3331 Kimberly Road                      +1 916 677 6607 (voice)

Cameron Park, CA 95682                  +1 916 677 3442 (fax)

 

 

From: UDSD073 at DSIBM.OKLADOT.STATE.OK.US (Mike Andrews)

Newsgroups: rec.org.sca

Subject: Re: Pearl harbor and Francois Viete

Date: Mon, 20 Mar 1995 14:18

Organization: The University of Oklahoma (USA)

 

In article <199503162253.RAA16091 at math.bu.edu>,

jeffs at math.bu.EDU (Jeff Suzuki) writes:

 

>      ...     and the greatest (or best known) cryptanalyst in period

>was the French mathematician Francois Viete, who regularly decrypted

>the Spanish military codes.  The Spaniards, who couldn't figure out

>why the French were beating them (well, who wouldn't be), accused

>Viete of witchcraft.  Anyone know where I can get details of the case?

>I.e., specific accusations, the outcome (if any -- IMSC, the charges

>were pretty much ignored), etc.?  Also, what _was_ the Spanish

>military code of the time, that Viete could decrypt it?

 

David Kahn, in his book _The Codebreakers_, says that the

Spanish nomenclator given to Moreo "consisted of the usual

alphabet with homophonic substitutions, plus a code list of

413 terms represented by groups of 2 or 3 letters

(LO=_Spain_, PUL=_Navarre_, POM=_King of Spain_) or of two

numbers, either underlined (underlined-64=_confederation_)

or dotted (overdotted-94=_Your Majesty_). A line above a

two-digit group indicated a null." (Kahn, p. 117)

 

Kahn defines a nomenclator thus:" ... a system that was half a

code and half a cipher ... . It usually had a separate cipher

alphabet with homophones and a codelike list of names, words,

and syllables." (Kahn, p. xv)

 

Kahn further says,

    "Meanwhile, Philip had learned, from his own

    interceptions of French letters, that Viete had broken

    a cipher that the Spanish -- who apparently knew

    little about cryptanalysis -- had thought unbreakable.

    It irritated him, and thinking that he would cause

    trouble to the French at no cost to himself, {he} told

    the pope that Henry could have read his ciphers only

    by black magic. But the tactic boomeranged.  The pope,

    cognizant of the ability of his own cryptologist,

    Giovanni Batista Argenti, and perhaps even aware that

    papal cryptanalysts had solved one of Philip's ciphers

    30 years before, did nothing about the Spaniard's

    complaint; all Philip got for his effort was the

    ridicule and derision of everyone who heard about it."

    (Kahn, p. 118)

 

>William the Alchymist

--

udsd007 at ibm.okladot.state.ok.us    (192.149.244.136)

Michael Fenwick of Fotheringhay, O.L. (Mike Andrews) Namron, Ansteorra

 

 

From: john.robarts at mercopus.com (John Robarts)

Newsgroups: rec.org.sca

Subject: Cryptography in Period (w

Date: 27 Mar 95 23:19:00 GMT

Organization: Mercury Opus BBS - St. Petersburg, FL - 813-321-0734

 

SH>\<< Henry Troup quoth unto All thusly >>/

 

SH>HT> From: hwt at bnr.ca (Henry Troup)

 

SH>HT> In article <199503162253.RAA16091 at math.bu.edu>, jeffs at math.bu.EDU

>HT> (Jeff Suzuki) wrote:

 

SH>...

>> cryptography, and the greatest (or best known) cryptanalyst in period

>> was the French mathematician Francois Viete, who regularly decrypted

>> the Spanish military codes.  The Spaniards, who couldn't figure out

>> why the French were beating them (well, who wouldn't be), accused

>> Viete of witchcraft.  Anyone know where I can get details of the case?

>> I.e., specific accusations, the outcome (if any -- IMSC, the charges

>> were pretty much ignored), etc.?  Also, what _was_ the Spanish

>> military code of the time, that Viete could decrypt it?

 

<snip>

 

SH>What cipher did Shakespeare use? I've heard he wrote some things (his

>epitaph?) that have never been satisfactorily decoded...

 

SH>(Anyone know more about this?)

 

Indeed! The Bard used a "bilitteral" cipher. That is, he used two

VERY slightly different fonts as he wrote. For instance, the trailing

end of a capital letter "A" would be slightly longer in one font than

the other. As he wrote, each letter would be selected from one font or

the other to produce five letter code groups. If you were to designate

one font as "A" and the other one as "B" then the groups could be

represented by combinations such as these: aabba aaaaa bbabb ababa bbaaa

aabbb babab etc. etc. Each of these groups represent a letter, usually

in order. Like A=aaaaa B=aaaab C=aaaba D=aaabb etc. etc. .... (Please

note this is a BINARY format very much like ASCII!!!!!!!!!)

 

Anyway, from this point the decoded letters are compared to a

"slip wheel". A slip wheel is simply two rings, one inside the other,

each with the alphabet inscribed on them. The rings may be rotated

against one another to align different letters together. This part is a

straight substitution cipher. For example: A=C, B=D, C=E, etc. etc. ...

or any other displacement value. Knowing which displacement to use can

only be determined through trial by error, by looking for subtle clues

within the body of the ciphertext itself, or by application of suitable

cryptologic mathematics. Recognition of the plaintext at this point is

possible but often not obvious as it was usually written BACKWARDS!

 

Of course the Gentleman in question may have used many other

techniques.

 

I hope this information is a help. Wouldn't it be nice if there

were some nice GIFs of the original manuscripts!!

 

Corwin ap Arawyn

 

 

From: john.robarts at mercopus.com (John Robarts)

Newsgroups: rec.org.sca

Subject: Cryptography in Period (w

Date: 10 Apr 95 01:19:00 GMT

Organization: Mercury Opus BBS - St. Petersburg, FL - 813-321-0734

 

MA>Reply-To: udsd007 at dsibm.okladot.state.ok.us

 

MA>In article <5939.1402.uupcb at mercopus.com>,

MA>john.robarts at mercopus.com (John Robarts)  writes:

 

MA>>Indeed! The Bard used a "bilitteral" cipher. That is, he used two

MA>>VERY slightly different fonts as he wrote. For instance, the trailing

MA>>end of a capital letter "A" would be slightly longer in one font than

MA>>the other. As he wrote, each letter would be selected from one font or

MA>>the other to produce five letter code groups. If you were to designate

MA>>one font as "A" and the other one as "B" then the groups could be

MA>>represented by combinations such as these: aabba aaaaa bbabb ababa bbaaa

MA>>aabbb babab etc. etc. Each of these groups represent a letter, usually

MA>>in order. Like A=aaaaa B=aaaab C=aaaba D=aaabb etc. etc. .... (Please

MA>>note this is a BINARY format very much like ASCII!!!!!!!!!)

 

MA>>Anyway, from this point the decoded letters are compared to a

MA>>"slip wheel". A slip wheel is simply two rings, one inside the

other, MA>>each with the alphabet inscribed on them. The rings may be

rotated MA>>against one another to align different letters together.

This part is a MA>>straight substitution cipher. For example: A=C, B=D,

C=E, etc. etc. ... MA>>or any other displacement value. Knowing which

displacement to use can MA>>only be determined through trial by error,

by looking for subtle clues MA>>within the body of the ciphertext

itself, or by application of suitable MA>>cryptologic mathematics.

Recognition of the plaintext at this point is MA>>possible but often not

obvious as it was usually written BACKWARDS!

 

MA>This "slip wheel" is actually the cipher disk invented, to

MA>the best of my knowledge (and that of David Kahn) by Leon

MA>Battista Alberti, who was born about 1404.

 

.... so some claim. Actually the "slip wheel" was a natural

development of a VERY MUCH OLDER system. i.e. *LONG strips of

narrow paper or cloth are covered with what appear to be random

letters. Only when the strip is carefully wound around a

cylinder of an exact and specific diameter can the plaintext be

read. Of course this type of code was not too hard to break.

However as an expediant means of secure communication it had

good use, a cylinder of the precise diameter would not likely be

close a hand and very considerable effort would have to be used

to arrive at the correct size. Further more the key was VERY

easy to remember! And even if the user had trouble remembering

the correct size it would be a very simple matter to keep an

innocent "token" to guage the diameter, for instance, a walking

stick, dagger handle, or maybe even his FINGER!

 

MA>Let me commend to your attention, and to the attention of

MA>all, the chapters of David Kahn's book _The Codebreakers_

MA>entitled "Ciphers in the Past Tense" and "The Pathology of

MA>Cryptography", which deal with the ciphers alleged to have

MA>been used by Shakespeare.

 

Well, I just this very minute finished rereading "Ciphers in the

Past Tense" from "The Code Breakers" by David Kahn. And it MAKES

no mention of Shakespeare AT ALL ! I also would have liked to

read " The Pathology of Crytography" in the same book, BUT IT

DOESN'T EXIST. If you ever get a copy of this book however you

can find the Bard mentioned on pages 184-185, 416, 459. Nothing

there really refutes Shakespearean use of Cryptology.

 

MA>>Of course the Gentleman in question may have used many other

MA>>techniques.

 

MA>done a largish amount of reading in the past 35 years. William

MA>and Elizabeth Friedman did a great deal of work along these

MA>lines at Riverbank Laboratories, and (with Dr. Fred Miller of

MA>the FBI) utter demolished a principal proponent of the thesis

 

A careful look at their feeble attempts at "The Beale Code" will

call into question their competancy in these matters. However

this line of thought is probably more suited to another echo.

 

MA>that Shakespeare's First Folio contained messages in a

MA>biliteral (Baconian) cipher.  Frederick Goudy, the

MA>typographer, drove the final nails into the coffin of this

MA>thesis, concluding that a multiplicity of typefaces had been

MA>used, instead of just two.

 

... well maybe, you argue it that way, however, they Still break down

into a very good semblance of TWO groups.

One of the greatest problems in the Study of Historical Cryptology in

our modern adherance to precision. In past times the naturalistic

environment let to a more defocused developement. For example a modern

computer doing a word search would not recognize that the letter "r" may

mean "are", "u" = "you" etc. etc.

 

MA>>Wouldn't it be nice if there

MA>>were some nice GIFs of the original manuscripts!!

 

MA>I'd like to have the GIFs for their own value, which (IMHO)

MA>is considerable.

---

 

 

Date: Thu, 11 Dec 1997 22:49:42 -0500 (EST)

From: "Charles J. Cohen" <charles at eecs.umich.edu>

To: sca-arts at raven.cc.ukans.edu

Subject: Re: Espionage

 

>I am currently searching for information on period espionage. I am unable to

>locate any outside of what I already have. Does anybody out there have any I

>dea where i can get my hands on period material, without having to write the

>CIA.

 

This might not be what you are looking for, but...Cryptanalysis sort

of started around 1589.  Spain had a 600 character cipher, which was

changed periodically and thought to be impossible to break. Henry IV

gave the problem to the mathematician Francisus Vieta, who decoded

it.  The French used it for two years, decoding secret Spanish

documents.  Philip II of Spain complained to Pope Sixtus V that the

French must be using sorcery ...

 

- Midair

 

 

From: Joe Skeesick <jskeesick at mmcable.com>

Newsgroups: rec.org.sca

Subject: Re: Codes and Ciphers

Date: Sat, 30 Oct 1999 14:48:09 GMT

 

Deykin ap Gwion wrote:

> Just finished reading Kahn's The Code breakers and was wondering if

> anyone knows details about in-period cryptographic systems...  I'm sure

> I could invent multiple substitution ciphers which would work

> substantially like Period crypts would, but I'm looking for any detailed

> analysis of in period systems...  I'm sure the Florentine and Star

> Chamber would have used them aplenty.

>

> Deykin

 

Not specifically the type of crypto you are referring to but......

 

In a program hosted by Terry Jones (I will look back through some things see

if I can find the name of it wasn't "The Crusades") He spoke of different

signal codes. One of particular interest was where two Roman out posts both

with barrels of water and a floating stick with a series of messages marked

on it (i.e. "all clear", "replacement needed", "this job sucks", et) a torch

was waved, both barrels plugs were opened and the water was drained, when

the signal torch went up again the hole was plugged. The message then in

line with the top of the barrel was the one passed.

 

With such "fail safe" messaging systems like that, no wonder there were more

than one instance of communication break down.

 

I will look up the film info since I'm fairly sure he actually went on to

speak about some actual cryptographic systems of the time, which would give

you places to start in your study since even those references would be just

surface glances compared to what you seem to want.

 

Janos

 

 

Date: Sat, 23 Oct 1999 19:42:51 -0400

From: james koch <alchem at en.com>

Organization: alchem inc

Newsgroups: rec.org.sca

Subject: Re: Codes and Ciphers

 

Joe Skeesick wrote:

> I will look up the film info since I'm fairly sure he actually went on to

> speak about some actual cryptographic systems of the time, which would give

> you places to start in your study since even those references would be just

> surface glances compared to what you seem to want.

>

> Janos

 

You might also read Strategemata(sp?) by Frontinus.  He writes of all

sorts of trickery used in classical warfare, though I can't remember any

specific references to codes.  Of course the Pythagoreans supposedly

used mathematical encryption.  Julius Caesar mentions in his Bello

Gallica(sp?) how while surrounded during a siege, the Romans sent

couriers through the enemy lines with letters written in Greek which the

Gauls of that region could not read.  During the middle ages the most

notorious users of codes were the alchemists.  Of course at that time

encryption was really not a major concern since widespread illiteracy

and the fact that (at least in Europe) most writing was done in Latin or

Greek made letters inherently more private (assuming you and the

intended recipient could read and write).  If you want a really

interesting (though suspect) book on the subject of classical and

medieval encryption, read The White Goddess.  It describes the training

of Druids in the use of hand and body signals.  This was supposedly used

by them to secretly share information while in the presence of

outsiders.  It made the local yokels believe the Druid priests had real

magical powers.  They supposedly developed the techniques used to this

day by faith healers, and stage psychics.  

 

Jim Koch (Gladius The Alchemist)

 

 

Newsgroups: rec.org.sca

From: djheydt at kithrup.com (Dorothy J Heydt)

Subject: Re: Codes and Ciphers

Organization: Kithrup Enterprises, Ltd.

Date: Sat, 30 Oct 1999 19:49:13 GMT

 

james koch  <alchem at en.com> wrote:

>Joe Skeesick wrote:

>... read The White Goddess.

 

No, *don't* read The White Goddess.  Not if you're looking for

information.  (If you just want a fun read, go right ahead.)

Graves, whenever he didn't have enough information, just *made it

up.*  So did Marion Zimmer Bradley; so do I; but we don't market

the result as scholarly research, but as fantasy fiction.

 

Dorothy J. Heydt

Albany, California

djheydt at kithrup.com    

                   http://www.kithrup.com/~djheydt

 

 

From: Lou Stewart <lhs at jobe.net>

Newsgroups: rec.org.sca

Subject: Re: Codes and Ciphers

Date: 31 Oct 1999 03:20:12 GMT

 

Deykin ap Gwion wrote:

> Just finished reading Kahn's The Code breakers and was wondering if

> anyone knows details about in-period cryptographic systems...  I'm sure

> I could invent multiple substitution ciphers which would work

> substantially like Period crypts would, but I'm looking for any detailed

> analysis of in period systems...  I'm sure the Florentine and Star

> Chamber would have used them aplenty.

>

> Deykin

 

One of the better known ciphers was the one used by Mary Queen of Scots

and her associates when they were conspiring to assassinate Elizabeth

and put Mary on the throne.  When the code was broken by agents of Sir

Francis Walsingham, Elizabeth's principal secretary, the messages

implicated Mary and six or seven main conspirators, and they were all

eventually executed.

Mary's grandson, Charles I, was also undone in connection with ciphers,

but that is another story, and out of period.  :)

 

In service, Luigsech ni Ifearnain

 

<the end>



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