In an article entitled “Foreign Office says no to MIA report” (16 December 2010 ) the Jewish Chronicle reported that:

“The British government is refusing to release documents which could shed light on the fate of three Israeli soldiers missing since 1982 because it says sensitive information could harm diplomatic relations with Syria.“

This statement seems to intimate that the Syrians have a hand in the 28-year ongoing travesty of human morality and decency.  This is not surprising, given Syria’s track record of human rights.  The fact that the British government is a partner to this travesty is somewhat more surprising.

Don’t assume that the British are the only ones withholding information about the three Israeli soldiers missing in action.  On 2 August 2009 I submitted a formal request from the National Security Agency (NSA) and the Central Security Service (CSS) under the Freedom of Information Act (FOIA) regarding the Israeli MIAs.  In the request I wrote:

Persuant to the Freedom of Information Act (FOIA), I hereby request the following information that exists or is archived in NSA:

• Information related, or pertaining, to all Israeli MIAs (“Missing In Action”) in the Sultan Yakoub (or Sultan Yaqub) battle in Eastern Lebanon on June 11, 1982, the sixth day of the Israel-Lebanon War.
• Intelligence reports related to any of the Israeli MIAs referred to, from 1982 to the present date.
• The request is specific to all, or all, of the following MIAs:
  • Zack Baumel
  • Zachary Baumel
  • Zecharia Baumel
  • Tzvi Feldman
  • Zvi Feldman
  • Yehuda Katz

A week later I received NSA’s reply (page 1 and page 2) in the mail.  The relevant part said:

“We have determined that the fact of the existence or non-existence of the materials you request is a currently and properly classified matter in accordance with Executive Order 12958, as amended.  Thus, your request is denied … the FOIA does not apply to matter that specifically authorized under criteria …”

I suspect that behind the legalese lies the fact that NSA/CSS is privy to information regarding the Israeli soldiers, but political expediency prevents the Americans, like the British, from doing what is morally correct.

It remains to be seen if WikiLeaks will shed any further light on this perversion of human decency.  In any case, here’s one person who wishes Miriam Baumel the best of success in releasing the British report on her son and the other MIAs.

The Cell Phone Audio Guide Service is meant to be used by visitors to the National Cryptologic Museum. Many of the exhibits in the museum have an item number associated with the exhibit. If you have a cell phone, you can call up a service number, enter the item number, and get a two minute explanation of the exhibit.

Although I live in Israel, I do have access to a VOIP phone, so I dialed the number in the press release and got the recording. The problem was I didn’t know what item numbers to input when prompted. An e-mail to the Museum requesting a list of item numbers was promptly answered within the hour by Patrick Weadon, the museum’s curator. The item list (which you can download from here) contains the following topics:

• Welcome
• Introduction
• History
• The Civil War
• The Zimmerman Telegram
• The Black Chamber
• Pre WWII
• Enigma
• Purple
• WWII and the Pacific
• SIGABA
• Cold War Espionage
• Secure Voice
• Electronic Secure Voice
• The Weak Link — People
• Technology
• Airborne Reconnaissance
• Women in Cryptology
• Special Recognition

Each of the topic listed has numerous sub-topics, so be sure to check out the item list.

It was a pleasure listening to excellent explanations about cryptologic and cryptanalytic topics where the terminology is correct and exact (e.g., no messing up the terms ‘code’ and ‘cipher’, getting their facts correct).

If you’re planning a visit to the National Cryptologic Museum you might want to wait until you’re there to use this service. If not, it’s a cinch to call them up and get accurate and informative explanation on some fascinating cryptologic heritage.

In this blog I’d like to illustrate the concept of homonymic antonyms with some examples from the Torah, wrapping it all up with a surprisingly related anecdote from the musical world of Benjamin Britten, Julian Bream, and the classical guitar.

The Hebrew Maidservant

In the Book of Shemot (Exodus), chapter 21 verses 7 – 11, we read about the Hebrew Maidservant. Although somewhat anachronistic today, the Torah sanctioned the socially advanced notion of allowing a man who was absolutely destitute to ‘sell’ his minor daughter to a well-to-do family. The hope, as explained by the Rabbis, is that either the master or his son would eventually take the girl as their bride. If this blessed occasion did not take place by the time she was 12 years old, the girl was free to go, released from the employment.

In verse 8, we read:

In the sixth word position of the Hebrew verse is the word “LO”, spelled “lamed-aleph”. This is the way it is written in the Torah, and in this form is an adverb denoting “no” or “does not”. The phrase “asher lo ye’adah‘ then means “does not designate her”. This is known as the “k’tiv”, the written Torah tradition.

But the ancient Rabbis passed us the oral tradition, believed by traditional Judaism to reach back to the giving of the Written Torah on Mount Sinai: although written using the letters “lamed-aleph“, the word should be pronounced as if it were spelled “lamed-vav” (it, too, pronounced as “LO”). In this form, the word means “to him” or “should”, and the phrase “asher lo ye’adah” means “does designate her” or “should designate her”. Pronouncing a word differently than the written form is known as the “k’ri”, the oral Torah tradition.

Here we have what appears to be a contradiction: is the word “LO” to be read as “does not” or as “does”?

The Talmud (Kiddushin 19a) explains the above quandary as follows: the Torah wants to tell us two different but related ideas with the single word “LO”. The written verse indeed refers to what will happen should the master decline to designate the maidservant, while the oral word refers to the ideal situation — that the master should designate her as his wife.

Edible Locust

We find another example of the Hebrew word “LO” as written (“k’tiv”) and as pronounced (“k’ri”) in the Book of VaYikra (Leviticus), chapter 11 verse 21. The verse, which describes those species of locust which are kosher, is found within a larger section discussing kosher and non-kosher animals, birds, and insects:

Once again, the word “LO” has a written and an oral tradition. This time, however, the interpretation is critical: if practiced as read, one may eat locust that do not have knees extending above their feet, while the oral tradition indicates the exact opposite — one may only eat locust that have extended knees. For a Jew committed to the oral Torah, this will make the difference between eating a kosher locust or committing a culinary abomination. Without Jewish rabbinic tradition one would be lost in deciding which is the correct interpretation.

As before, rabbinic tradition consistently explains the verse as follows. The oral tradition (“k’ri”) of “lamed-vav” (i.e., “it has”) makes the phrase “asher lo chera’ayim mima’al leraglav” mean “which has extended knees above its feet”. Indeed, halachically, one may eat specific known types of locust that have extended knees (if it is one’s tradition to do so).

The Torah, however, imparts another halachic principal with the written tradition (“k’tiv”): even if the locust is a young one and has not yet (“LO” meaning “no” or “not”) developed its extended knees, since it will eventually do so (“LO” as “it has”), you may eat it at any point in its development cycle.

Houses in Walled Cities

As our last example of a homonymic antonym we have a verse from VaYikra (Leviticus) chapter 25 verse 30. The verse is found in the section that teaches us that a house in a walled city is not returned to its original owner in the Jubilee year if it hadn’t been redeemed within a year of the transaction:

By now we’re familiar with the quandary: is it a house in an unwalled city or a walled city that does not return to its original owners in the Jubilee year? As in the previous example, the oral tradition takes precedence: a house in a walled city must be redeemed within a year. If not, it does not return to the owners in the Jubilee.

But the written tradition teaches us another important halachic (legal) law: if the city was walled at some time in its past (the oral form), even if it is unwalled today (the written form), it is considered legally to be a walled city.

The idea behind written versus oral traditions

If we summarize the ideas above, we see a consistent Rabbinic method of interpreting written and oral forms of a word in the Torah: both forms are meant to impart important information. Although only one form can be the one actually pronounced, a person should keep both meanings in mind when reading the passage. This has a distinctly Zen-like meditative feeling to it — the existence of two diametrically opposing ideas co-existing consistently in a real world.

Benjamin Britten, Julian Bream, and written / oral traditions

One of my loves for the past thirty years has been playing the classical guitar, and one of my heroes has been the world-renowned guitarist Julian Bream. His fascinating biography, “Julian Bream: A Life on the Road” by Tony Palmer, is an intimate and personal portal into the wonderful and difficult world of a concert virtuoso.

Julian Bream is pre-eminent among contemporary British virtuosi for encouraging modern-day composers to write music for the classical guitar. Bream was successful in getting Benjamin Britten, the famous English composer, to write one of the masterpieces of contemporary guitar literature, the Nocturnal, opus 70.

On page 87 Tony Palmer writes:

‘When the piece first arrived,’ Bream told me, ‘I found I didn’t have to change anything, not one note. It’s the only piece written for me of which that is true. Oh yes, except for one tiny blemish where Britten had contrived to place two notes on the same string, which was naturally impossible to play. When I pointed this out to him he was simply horrified! It was as though you had pointed out some terrible gaff in his social behaviour. He said “Oh my God! Julian! How did I do that?” And I said, “Well, Ben, there it is. There’s a B♭ and a C♯, and I’ve only got one A string to play them on.” He looked at it, and he looked at it again, and he then said: “Look, I’ll tell you what, Julian. Let’s put one of those notes in brackets, so that when you come to play the piece, play the C♯ and just think of the B♭.” That’s rather nice, don’t you think?’

Play the C♯ and just think of the B♭. An unexpected parallel to the Torah’s concept of k’ri and k’tiv, oral and written forms, from the enchanting world of music.

The National Archives

Many thanks to Mike Cowan for a link to an internal sub-tree of The National Archives (UK) with a plethora of links to valuable cryptographic material related to the Government Code and Cypher School (GCCS) and Government Communications Headquarters (GCHQ) between the years 1914-1979.

Quoting from the web site, the site contains “general records of the Government Code and Cypher School (GCCS) and Government Communications Headquarters (GCHQ) relating to responsibilities for intercepting enemy communications, particularly during the Second World War, and for ensuring security of the government’s electronic communications“.

The records span the years 1914-1979 and included the following general categories:

• Senior management papers
• Soviet communications
• Japanese military communications
• Histories and personal papers
• German military communications
• Bulgarian, Croatian, French, Iranian, Italian Portuguese and Spanish communications
• Diplomatic, commercial and meteorological communications
• Liaison with allied organisations
• Communications security
• Field signals intelligence
• Technical matters
• Intercepted plain language communications
• Wireless Telegraph Section
• GC&CS Administration
• Research Section

For those with access to the National Archives in London, there is material here to keep one busy for years.

Cryptanalytic program written in Perl

I’ve been a computer programmer since the early 70′s, about the time I became enamoured with cryptanalysis.  Writing computer programs to aid my cryptanalytic research has been invaluable to me throughout this entire period.  Sure, I have spent delectable hours solving ACA-type cryptograms by hand.  When I worked on more serious ciphers in university, however, computers have always been invaluable and time-saving.

My first cryptanalytic programs were written in PL/1 and ran on IBM mainframes.  The speed of these babies matched that of modern day PCs.  In the 80′s I “graduated” to PCs running compiled C code and the occasional AWK scripting program to help analyze and solve more sophisticated ciphers.

For many years my cryptanalytic scripting language of choice was AWK.  When all I wanted to do was parse the ciphertext, perform a frequency count, and perform some complex analysis, a scripting language is light enough for the classic edit-run-debug loop.

A few years later I moved on to Perl.  Here was a scripting language that let me do anything I pleased in a minimal amount of coding time.  My research output increased significantly and I was able to produce important results I could never have done by hand.

An example of results I could never have done manually is the initial work I did on John F. Byrne’s Chaocipher.  Sifting through the 13,300+ characters of Exhibit 1, looking for pt/ct identities, plaintext and ciphertext double letters, isormorphs, trawling a pattern through the plaintext or ciphertext looking for a match, performing statistical calculations, simulating alternative cipher models and enciphering the 13,300+ plaintext characters — these are only a few of the tasks that scream out for automation using computers.

Recently I spent time trying to solve a single ADFGVX ciphertext challenge message.  The tremendous amount of tedious and error-prone computations and calculations needed to match columns would take days to perform, so I wrote some help program (in Perl) that let me concentrate on the analysis without getting bogged down in the “drudgery”.

Up-and-coming cryptanalytic techniques we’re seeing more and more are Hill-Climbing and Simulated Annealing (SA).  You can only take advantage of these powerful methods if you can write a program to do it for you.

You don’t need to study Advanced Computer Science to be able to write computer programs.  Pick a language (e.g., Perl, C, C++, Ruby, Python, Visual Basic, Java) and start writing simple programs: reading text from a file, taking a frequency count, writing to standard output, manipulating characters and strings, loops, and performing mathematical calculations.  In a short time you will have mastered everything you need to write cryptanalytic aids.

Don’t worry if you don’t know the difference between a double-linked list and a B-tree.  Just program the method you would use if you were solving it by hand.  This alone will cut your solving time by 1-2 magnitudes.

In my opinion, every cryptanalyst should know how to write computer programs to ease the work.  And I believe anyone can acquire that skill.

Don’t lose out on advancing in the world of Classical Cryptanalysis because the problem key space is too large for manual solution and you can’t program.  Take that step, come on into the modern world, and let your cryptanalytic achievements soar.

This past week I searched for “PURPLE” in Google’s image database (I think that’s what I did — it was oh so many link clicks ago ).  Perusing the booty uncovered a link to a link to a link etc. until I chanced upon some cryptographically-related photo collections on Flickr.  I have spent many an hour since enjoying the eye candy there and in other locations.  I’d like to share some of these sites with you.

Brewbooks: Trip to the National Cryptologic Museum 13 Feb 2009

This treasure trove by J Brew resides on Flickr, with the cryptologic-related photos beginning here.  Get ready for an abundance of “eye candy” by an extremely talented photographer (check out his other photo collections to convince yourself you’re in the presence of a master).  The photographs are incredibly clear, allowing you to read book titles, exhibit text, and see precise details of devices.

Mr. Brew (here’s his photo) has kindly provided very descriptive texts for all of the photos, enabling you to learn a great amount of information while feasting your eyes on them.  In addition, many of the photos have hotspots: position your cursor over the hotspots for more detailed descriptions.  Run it as a slide show for the best photographic clarity.

Here’s a list of photos that caught my fancy:

• Linguists in NSA: impressive biographies of Dr Sydney Jaffe, James R. Child, Norman Wild, and John B. Hurt
• Clear photos of numerous cryptographic devices (e.g., TUNNY, STURGEON, Enigma, and many more machines)
• Enigma daily keys list
• Japanese Navy RED Cipher Machine
• JADE Japanese Cipher machine
• US Navy Cryptanalytic Bombe and M-9 Bombe Checking Machine
  • Be sure to read the description and hotspots on the Bombe photo! (Here’s a link to mouth-watering pictures of a reconstructed British Bombe at Bletchley.)
• Original (censored!) drafts of David Kahn’s “The Codebreakers”

Brew’s photos of book shelves of the library of the National Cryptologic Museum (starting here) had me salivating.  His photos are crystal clear, sharp enough to make out many of the titles, of which I mention those classic texts that caught my eye:

• Photo #1
  • The Shakespearean Ciphers Examined (WF and E Friedman)
  • The Puzzle Palace (Bamford)
  • Bazeries Military Cipher (Rosario Candela?)
  • Yardleygrams (Herbert O Yardley)
  • Enigma (Wladyslaw Kozaczuk)
  • Elementary Cryptanalysis (Helen F Gaines)
  • The Codebreakers (Kahn)
• Photo #2
  • An issue of Cryptologia
• Photo #3
  • Language-related books
  • Dictionaries
  • Several of Kahn’s books
  • The Story of Magic (Frank B. Rowlett)
• Photo #4
  • Intelligence-related books
• Photo #5
  • Cryptanalysis for Microcomputers (Caxton Foster)
  • Dalla scitala all’Enigma (“From the Skytale to the Enigma”, Italian), Filippo Sinagra, 2001 (see review in Cryptologia)
  • L’art de déchiffrer. Traité de déchiffrement du XVIIe siècle, J. P.  Devos et H. Seligman, 1967.
• Photo #6:
  • Un problème de cryptographie et d’histoire (General Cartier, 1938)
  • An Annotated Bibliography of Cryptography (David Shulman, 1978)
  • Cryptology (Beutelspacher, Albrecht, The Mathematical Association of America)
  • Codes and Ciphers (D’Agapeyeff)
  • Précis de cryptographie moderne (Charles Eyraud, 1953)
• Photo #7: Computer-related cryptography
• Photo #8
  • Red Sun of Nippon (novel by Herbert O Yardley)
  • Applied Cryptology, Cryptographic Protocols, and Computer Security Models, Richard A. Demillo (Editor)
  • In Code: A Mathematical Journey (Flannery)
  • Decrypted Secrets (F L Bauer)
• Photos #9-13: Selecta of Mathematical Papers

Military Cryptanalytics Part I

Uploaded to Flickr by “Travelin’ Librarian”, these are eight photos from this classic written by Friedman and Callimahos.

Who’s Who in American Cryptology

These photos (by austinmills) constitute excellent biographies of American cryptologic luminaries.

I’m sure this selection of photo collections only touches the tip of the iceberg.  As such, I believe they will be of interest to fellow amateur cryptologists.

When I started this blog a few months ago I encountered many sites I wanted to monitor on a regular basis.  For example, I wanted to monitor several pages deep within the NSA web site for changes.  Unfortunately, most of these sites have a common problem: they have no RSS feeds.  So I used the same method I’ve used for years: periodic manual checking.

At some point even I threw up my hands.  The work involved in checking an ever-growing list of sites was becoming too painful.  At that point I searched for, and found, a better and free solution: ChangeDetection.com.  It’s changed my life and I’d like to share it with you.

ChangeDetection.com defines itself as follows:

At your request, we monitor any website page for text changes. If a change is detected we send you a notification email. We also maintain a log of recent changes to the page and allow you to see the difference between any two versions of the page.

After registering yourself with ChangeDetection.com, monitoring any Web page is simplicity itself.  Select the “monitor a page” option, enter a page address, give it an e-mail address to send notifications to, tweak optional features, and you’re done.  And you can monitor any number of pages to your heart’s content.

When any of your monitored pages change, you will be notified of the exact changes by e-mail.  The service also records the full history of this site, showing you all changes (or inactivity!) over time.

Another great feature is the ability to enable visitors to your web page to register for notification when your page changes.  If your site lacks a built-in RSS feed, if you’re too lazy to maintain one, or if you want to enable non-techie visitors to know when your page changes, just insert some HTML code that provides a simple-to-use interface (see my Chaocipher Clearing House site for such a feature).  You can even tell how many people are currently monitoring your web page.

Although I’m a late adopter, when I finally adopt some technological feature I know I need it and I’m happy with it.  ChangeDetection.com has changed my blogging experience, enabling me to concentrate on blogging,   Don’t leave home without it.

The US Army Field Manual 34-54 on Battlefield Technical Intelligence is freely available on the Web.  Here is a description of this manual as taken from the manual itself:

This field manual provides guidance to commanders and staffs of military intelligence (MI) and other units responsible for technical intelligence (TECHINT) or having an association with TECHINT. It provides general guidance and identifies the tactics, techniques, and procedures (TTP) used in the collection, exploitation, and dissemination of TECHINT in satisfying the warfighter’s requirements.

Appendix G, entitled “Foreign Language Text Recognition”, is a concise and educational lesson on how to recognize a foreign language in unknown text.

Quoting from Appendix G:

When TECHINT personnel are able to correctly identify foreign languages used in documents or equipment, it has two immediate benefits. First, it helps identify the equipment or type of document and where or who is using it. Second, it ensures that TECHINT personnel request the correct linguistic support.

This appendix contains language identification hints that will enable TECHINT personnel to quickly identify some of the many languages used in documents, on equipment plates, and on other materiel. TECHINT personnel can speed up the entire battlefield TECHINT process by following the guidance herein.

For those of us who are, um, a little rusty and have forgotten the difference between a cedilla and a circumflex, this appendix will set you right.  Gone are the excuses for not recognizing a foreign language when you see one.

“An index of 4,923 entries containing approximately 1.3 million pages of previously declassified documents, which have been released to NARA is provided. The documents are from the pre-World War I period through the end of World War II.”

The links refers to a fascinating listing of cryptologic documents declassified by NSA/CSS in Project OPENDOOR (1996) and released to the U.S. National Archives and Record Administration (NARA) in Washington, D.C. In the very long, unsorted list one could easily overlook such gems as:

• William F. Friedman’s “Index of Coincidence and its Application to Cryptography” (# 504)
• Friedman’s “Analysis of a Mechanico-Electrical Cryptograph, Part I and Part II” (#1874)
• Yves Gylden’s “Analysis, from the Point of View of Cryptanalysis, of ‘Cryptographer Type C-36′, Etc.” (#62)
• “Converter M-134-A (Sigaba) Photographs Wiring Diagrams” (#3256)
• “Cryptanalysis of the Tunny Cipher Device” (#2750)
• “British Description of Spanish Air Force Wheatstone Cypher Machine” (#971)
• The famous “‘AF’ Message: Lack of Water for U.S. Air Unit at Midway – WWII” (#3832)

and so much more.

As another example, reading the original unsorted listing also conceals the fact that the list refers to 79 different variants with the Japanese system “JN-*” designator (beginning with JN-11, JN-11D, JN-11G, JN-12, JN-14-J up to JN-73, JN-74, JN-7A, and JN-87).

To simplify access to the information in the list I’ve created a keyword index of the 4,922 entries (not 4,923 as described above — there is no NR 271). The raw list required manual corrections of spelling and formatting. It is my hope that this index will provide easier access to students of cryptology, helping to uncover easily-missed ‘jewels’.

In addition to the keyword index you can access the same list, this time sorted by the title.

Summarizing the offerings of the NSA/CSS declassified documents list:

• Keyword indexed
• Original list (formatted)
• Sorted by title

Should you be interested in reading specific documents in the list, check out NARA’s research page for information on visiting NARA or ordering copies.

Well, if you’re looking for an in-depth explanation of the Enigma, complete with a lucid mechanical description and mathematical underpinnings you can really sink your teeth into (and understand!) look no further. Check out Erik Vestergaard’s superb explanation of the Enigma’s mechanical, operational, and mathematical aspects. A Danish high school mathematics teacher, Vestergaard took his class on a study tour to London in 2007, and one of their stops included Bletchley Park. This site is a wonderful compilation of their experience in Bletchley, complete with mouth-watering, clear descriptions of how the Enigma works and how it was broken. Here’s a list of topics covered:

1. Introduction
2. The situation before Enigma – history briefly
3. How Enigma works
   1. Ring settings
   2. The notch
   3. Rotor arrangements
   4. Rotor settings
   5. Double stepping
   6. Plugboard settings
   7. Reciprocal property
4. Marian Rejewski and the Poles
5. Double encryption
   1. Daily key from the Code Book
   2. Message key
6. The mathematics used by the Poles
7. An article from Mathematics Magazine
   1. Polish Mathematicians Finding Patterns in Enigma Messages (861 kB)
   2. The mathematics behind the solution of Enigma (a guiding document) (165 kB)
8. The Bletchley Park era
9. The decryption procedure at Bletchley Park
10. Cribs
11. The Turing bombe
12. Enigma and the Turing Bombe in Excel VBA
    1. Enigma simulator in Excel VBA (101 kB)
    2. Turing Bombe simulator in Excel VBA (210 kB)
13. Our visit at Bletchley Park
14. Interactive resources/simulators
15. Links
16. Online literature
17. Film
18. Literature

Doubtless, Erik has left his students with an indelible love for history and mathematics. Man, I wish I had a math teacher like this when I was in high school.

Enjoy!