Korean Telegraphic Code

Hangul is an artificial alphabet created in the fifteenth century as a script for Korean. It is interesting because graphic units for consonants and vowels are combined horizontally or vertically to form syllable symbols. Because of this system, I think substitution cipher is not possible in Hangul script.
Once characters are encoded into digits or roman letters, encryption methods including substitution and transposition are applicable. Today's computer can of course handle Hangul characters. But in the early years of telegraphy, telegrams in Korea had to be in Chinese characters or Latin letters.
So, a telegraph codebook for Chinese characters were used in Korea.
I have seen a Korean version (『漢電』) of a Chinese telegraph codebook.
Even after WWII, it appears a telegraph codebook with similar content was used, in view of an edition adapted for use by those who could not read Chinese characters (Korean Telegraphic Code Book, with characters arranged by sounds in English alphabetic order according to the McCune-Reischauer system of transliteration).

These are already covered in 電碼――中国の文字コード, dealing with Chinese telegraph codes, in which I now made small corrections.

(By the way, I wrote the above ten days ago, but I couldn't upload it because my smartphone failed and I couldn't pass the two-factor authentication for logging into the blog.)

William Blencowe's "Safest and Most Expeditious" Cipher

I uploaded a new article "William Blencowe's "Safest and Most Expeditious" Cipher". Blencowe was a grandson of the celebrated mathematician and codebreaker, John Wallis.
The example ciphertext consists of an interesting mix of single letters and bigrams:

a.c.e.o.t.ds,th.al,th.an,th,es,an,my,be,m.n.t.o.nd,jo.H.sh,y,in.y.
A.w.n,th,e.de.in.pi.sa.I.A.g.su.r.to,ye,ho.e,th.c.wth,de.re,en.t.at,
r.il,ti.A.n.nb.te.sts,nd,ri.rm.ot,re,d,n.m.m.r.ar,nd,ar,ty,us.i.m.c
in,a.e,d,h,ro.to,y.ig.&,of,to,ou,a.b.d.g.f.p,no,n.is,d,a.p,k.
ye,b.th.th.of,u.m.n.hl.th.t.S.t.n.e.ye,xt,u.w.A.ho,en.o.w.Ja.I
th,l.F.pe,n.e,h,hi.rs,ar,ty,la.ki.a.r.in,e.fo.to.m,w.tw.th.nd,ng,Sr,
no.le,at,ey,th.gh,ar.ed,an.e.w.co.h.n,h,a.n.e.E.ey,pa.ou.d,an,is,as.
r.p.m,g.f.c,a.n.do,ll,b.m,d.g.b.d.m,p.q.b,s.r,d.c,a.n

After all, however, this is essentially a columnar transposition cipher with some additional twists. Using bigrams may mislead the codebreaker at first, but once transposition is suspected, they would help codebreaking rather than prevent it.

Can a Lost Encoding Format be Recovered by Analysis?

It's now a decade ago that I read in a newspaper article that data obtained on Mars by Viking spacecraft could not be read 25 years after the landing because the format was lost (The Asahi Shimbun, 20 January 2014). The case is also mentioned in a report on long-term data preservation by a Japanese think tank, CRDS (CRDS-FY2012-WR-07).
The source seems to be a news release of the University of Southern California (Spaceflight Now):

"The data were on magnetic tapes, and written in a format so old that the programmers who knew it had died," Miller said.
Eventually, NASA was able to recover the data from printouts, luckily preserved by Levin and Straat - and so, Miller was able to pore over the numbers.

After all, the issue is not about loss of a data encoding scheme but physical format of the magnetic tapes.

I got interested in this news because I was wondering whether "codebreaking" is possible for media data encoded on, say, DVD without knowing the format. (The compromise of the encryption system (Wikipedia) of DVD assumes knowledge of the format, and is thus another matter.) Considering the sheer number of pages of format documentation, I think it is near impossible. But of course, relying on secrecy of the scheme is not a good idea for cryptographic security. Security should rest on the key being kept secret (Kerchoff's principle).

By the way, the Viking data recovered in the 1990s was used to claim finding evidence of an organism on Mars (Miller's site, Levin's site). But the result is not established (Wikipedia).

Two More English Ciphers from the 1650s

I've been going through my notebook file these days, and uploaded some materials I left unfinished before. Now, I added two ciphers (Richard Browne, John Bramhall) in "King Charles II's Ciphers during Exile".

J.F.W. Herschel's Cipher Puzzle

I've been interested in ciphers that allow multiple readings (a Venetian example).
So, I took a note when I read about a ciphertext that yields two readings, posted by tonybaloney at:
http://www.aerobushentertainment.com/crypto/index.php?topic=36.60
(now it seems the link has changed).
The ciphertext (A) and the two readings (B,C) are as follows:

(A)Xabnsly ngpwpdetlews tbbbtzl aobl stheingdnxmccvv
(B)Several philosophers observe that chloroplatinate
(C)Sing, Celestial Muse, the destroying

(A)hclzepsf xo qskxybbbbui
(B)solution on silverplate
(C)wrath of Achilles,

(A)Egtubatjkh fba lwipizix eqjbnasv nfvj yjcin
(B)reproduces the luminous spectrum with great
(C)Peleus’ son, what myriad woes it

(A)cjzvekzxy gf nbyr gzrefcwxianst
(B)vividness in blue fluorescences,
(C)heaped on the Grecians,

(A)Jxkivu v xcnukwcxpv ifnnszp't tpdvm
(B)whilst a coppersalt insolated might
(C)Many a valiant hero’s soul

(A)lqaauuqrauaqqvso up mfijtxyz.
(B)photographically be coloured.
(C)dismissing to Hades.

Now, I find this ciphertext was posted by Klaus Schmeh on his blog Cipherbrain back in 2016: Wer knackt die Verschlüsselung des Astronomen John Herschel?. The article shows the source: The Photographic News, 5 January 1866 and identifies the author of the ciphertext as J.F.W. Herschel (1792-1871) (Wikisource). The blog readers found out additional information.
The weekly magazine (Google) carried the puzzle on 5 January 1866 (p.5-6), the solution (B) provided by a reader the next week (p.23), and Herschel's correct solution (C) the next week thereafter (p.35). After all, the reading (B) was wrong, and this cipher is not about double reading.
The readers of Cipherbrain worked out the general principle of this cipher: schorsch pointed out the first two words can be explained by word-by-word Caesar cipher, Norbert demonstrated this works for every word, and Thomas found the shift, counted in reverse direction, is the number of letters in the word plus 1, 2, 3, 4, ....
In the following, (a) is the ciphertext, (b) is the number of letters in the (deciphered!) word plus 1, 2, 3, 4, ..., (c) is the result of reverse-shifting, and (d) is the plaintext word.

(a)Xabnsly ngpwpdetlews tbbbtzl aobl  stheingdnxmccvv
(b)4+1=5   9+2=11       4+3=7   3+4=7 10+5=15
(c)Svwingt cvelestiatlh muuumse thue  desptyroyixnngg
(d)Sing,   Celestial    Muse,   the   destroying

(a)hclzepsf xo    qskxybbbbui
(b)5+6=11   2+7=9 8+8=16
(c)wraotehu of    acuhilllles
(d)wrath    of    Achilles,

(a)Egtubatjkh fba     lwipizix eqjbnasv nfvj    yjcin
(b)6+9=15     3+10=13 4+11=15  6+12=18  4+13=17 2+14=16
(c)Prefmleuvs son     whtatkti myrjviad woes    itmsx
(d)Peleus'    son,    what     myriad   woes    it

(a)cjzvekzxy gf      nbyr    gzrefcwxianst
(b)6+15=21   2+16=18 3+17=20 8+18=26=0
(c)hoeajpecd on      thex    gzrefcwxianst
(d)heaped    on      the     Grecians,

(a)Jxkivu  v       xcnukwcxpv ifnnszp't tpdvm
(b)4+19=23 1+20=21 7+21=28=2  5+22=27=1 4+23=27=1
(c)Manlyx  a       valsiuavnt hemmryo's socul
(d)Many    a       valiant    hero's    soul

(a)lqaauuqrauaqqvso up        mfijtxyz.
(b)10+24=34=8       2+25=27=1 5+26=31=5
(c)dissmmijsmsiinkg to        hadeost
(d)dismissing       to        Hades.

What remains unknown is (i) how the decipherer can know the number of letters in the deciphered word and (ii) how the decipherer can identify the letters to be discarded. The latter may be left to the decipherer's insight, but (i) is indispensable to allow proper deciphering.
Herschel presented this cipher as a challenge to believers of "an axiom that there is no cipher which cannot be read." I guess that in trying to make the puzzle more difficult, he forgot that the scheme need to be (difficult but) invertible.

A Cipher between Emperor Charles V and Young Prince Philip (1545)

A letter with a ciphered paragraph from Charles V to Prince Philip (1545) is presented on Spanish Ministry of Culture's website (pdf) and PARES' facebook page. The cipher turned out to be the same as the one broken by George Lasry and Carlos Köpte independently in 2023. So, I promoted the cipher as "Charles V-Prince Philip Cipher (1545)" in "Ciphers during the Reign of Emperor Charles V".

Variable-length Figure Cipher Used by Gilbert Gifford?

Speaking of variable-length figure cipher mentioned yesterday, I found in my notebook file a possibly relevant record:

"The words in italics are in cipher, only partly deciphered. The cipher for the most part consists of figures which run on without a break, and are thus capable of various solutions, according as they are taken as single or double numbers; and this sometimes prevents the deciphering of one passage by the aid of another."
From: 'Appendix: January 1588', Calendar of State Papers Foreign, Elizabeth, Volume 21, Part 1: 1586-1588 (1927), pp. 661-671. URL: http://www.british-history.ac.uk/report.aspx?compid=74826&strquery=cipher Date accessed: 06 May 2013.

This note belongs to a letter from Stafford to Walsingham from January 1588, but may refer to an enclosed letter from Gilbert Gifford (under the pseudonym of Francis Hartley) to Thomas Phelippes (M. Wilsdon).
Inspection of the original manuscript is desired.

Variable-length Figure Cipher used by Duke of Lorraine (ca.1620?)

I succeeded in reconstructing a cipher used in a letter to the Duke of Lorraine (ca.1620?) and uploaded it in a new article, "Variable-Length Figure Cipher of Duke of Lorraine (ca.1620?)". I abandoned this before, but I took it up again and this time, two occurrences of the word "temperament" provided a first clue. Unexpectedly, the cipher employed variable-length symbols. That is, code symbols consist of one to three symbols. Since the figures are written without a break, there was some difficulty in identifying code symbols corresponding to plaintext segments.
This kind of variable-length symbols written continuously without a break are often seen in Vatican ciphers. It is yet to be studied how this system came to be used by the Duke of Lorraine's correspondence.

Codebreaking of Sir Robert Southwell during the Popish Plot

The Popish Plot may refer to "a period of extraordinary political tension that took hold in England in 1678" (Fictitious treasons: 'The Popish Plot') instigated by revelation of a fictitious plot known by this name.
My notebook included a reference to Sir Robert Southwell's deciphering during this period since 2009, but I have not known whether this involved codebreaking or used a key obtained in a non-cryptographical way. The other day, I found Southwell himself wrote this was "without a key", which makes it interesting enough to be included in an additional section in "Ciphers of Coleman's Correspondence Discovered in the Popish Plot".
It's a pity it is not known specifically what cipher was broken by Southwell.

Duke of Ormond's Ciphers during the 1660s

I added a section "Marquis of Ormond's Correspondence" in "English Ciphers during the Restoration Period". It covers some reconstructed ciphers used by the Duke of Ormond, the Earl of Anglesey, the Earl of Arran, and the Earl of Longford.
The Ormond-Anglesey Cipher used in 1663-1664 appears to be based on a printed template of DECODE R433. This shows the template was used as early as 1663.

Cryptiana is now HTTPS-Enabled

Belatedly, I enabled HTTPS in Cryptiana. The other day, I happened to access Cryptiana on my mobile phone, and got a warning message that it's not secure because it is not in https. I found only one click is needed to enable HTTPS. Hopefully, mobile users have one less concern in using Cryptiana. It seems old links beginning with "http" is automatically redirected to "https" URLs.

Ciphers Used in Letters of Oliver Cromwell, Henry Cromwell, and Others

I updated an old article "Codes and Ciphers of Thurloe's Agents" for the first time since 2012. The original article was based on Thurloe State Papers in print, but I noticed the original manuscript is in Add MS in the British Library, based on which I added a new section "BL Add MS 4166". Although the title of the article refers to "Thurloe's Agents", ciphers used in letters of Cromwell (Add MS 4166, f.87-91) and his generals and ambassadors are also covered.
One scheme interesting for me is a kind of polyalphabetic cipher for Henry Cromwell (1656), in which a plaintext letter is represened by a pair of figures, of which the difference indicates the letter (Add MS, f.77-78, 118-119).

"A new Book of Cyphers" ... about Intertwined Initials

I came across a book, William Parsons' A new Book of Cyphers (1704)(Google) during a web search. For a moment, I expected it was about an invention of a cryptographic method, as in Samuel Morland's A New Method of Cryptography (1666), which I descrbied in "Samuel Morland's "New Method" Used for Charles II's Ambassadors". 

Actually, the "cipher" of this book refers to a symbol design made of intertwined initials. 

Such "ciphers" (or chiffres in French) are quite common and I mentioned them in "Great Ciphers of Napoleon's Grande Armée" (in the context of Empress Marie-Louise), "ウイリアム・ブレア「暗号」（1807）（『リース百科事典』）" (quoting from a definition of "cipher", "a kind of enigmatical character, composed of several letters interwoven together, fancifully" from Rees' Cylopaedia), and possibly others. Searching for "elizabeth cipher" (without quotes) on Google gives a Wikipedia page "Royal cypher" before my article about Elizabethan codes and ciphers.

Ciphers between Mazarin and Abbe Fouquet

I added some reconstructed ciphers in "Cardinal Mazarin and Ciphers". Thus far, the article mentioned "BnF fr.23202, which I have not seen" at one place, but recently I noticed it is available online.
One of the reconstructed ciphers is used in many letters in the period overlapping Mazrin's two exiles (1651, 1652).

Reading Scrolls Carbonized in Ancient Vesuvius Eruption without Unwrapping

PC's newsfeed made me aware of deciphering of text on carbonized ancient scrolls without unwrapping (NBC News). (This "deciphering" has nothing to do with cryptography.)
A whole library of an ancient villa survived centuries under the earth, carbonized by the heat of the volcanic eruption of Mount Vesuvius in AD 79, which engulfed Pompeii and Herculaneum, where the villa was located. The library contained more than 1800 papyrus scrolls, of which some were presented to Britain and France in the nineteenth century (Wikipedia).

Early attemps to read the content were a destructive study, breaking the carbonized scrolls into pieces ("The Library of the Villa dei Papiri at Herculaneum", reviewing David Sider (2005), The library of the Villa dei Papiri at Herculaneum; "Twelve Books at Herculaneum That Could Change History" by Richard Carrier).
In 2011, Brent Seales et al. reported "virtual unrolling" of a Herculaneum scroll (Brent Seales et al., "Analysis of Herculaneum Papyri with X-ray Computed Tomography" (NDT, Semantic Scholar)). Virtual unrolling or virtual unwrapping is a non-destructive modality and begins by scanning a scroll with X-ray tomography (as in a CT scan) to produce a 3D volumetric image of the scroll, in which single layers are identified by intensive manual labour ("segmentation"). Once layers are segmented, they can be mapped onto planar images.
At this stage, Seales could not detect any text because carbon-based ink could not be contrasted from carbonized papyrus with his X-ray scan. In 2016, Seales succeeded in revealing text of a scroll found at En-Gedi, Israel, that had been charred in a fire, in which the ink contained lead readily identifiable with X-rays.
Detection of carbon-based ink was achieved by using X-ray phase-contrast tomography, whereby a slight difference in thickness caused by the presence of ink can be detected in phase difference of X-rays. With this method, successful decoding of some fragments of two Herculaneum scrolls (PHerc. 375 and PHerc. 495) was reported in 2016 (Bukreeva et al. (2016), "Virtual unrolling and deciphering of Herculaneum papyri by X-ray phase-contrast tomography" (Scientific Reports), Stabile et al. (2021), "A computational platform for the virtual unfolding of Herculaneum Papyri" (NIH)).
Seales' team adopted an approach that combines scanning with high-energy X-rays with identifying ink by machine learning trained with image data with visible text in ink (The Guardian).
Seales' work inspired the Vesuvius Challenge, launched in March 2023 by Nat Friedman, Daniel Gross, and Brent Seales. It offered a Grand Prize for recovering 4 passages of 140 characters as well as smaller prizes for contributions on the way. It was reccognized that the task was not easy, and the organizers hired a segmentation team to manually identify and label the papyrus surface in the volumetric data (PHerc.Paris. 4) and provide the flattened segments as an open source. It led to discovery of "the first directly visible evidence of ink and letters" by Casey Handmer (his blog) and close collaboration between the in-house segmenters and contestants drove the work (Vesuvius Challenge 2023 Grand Prize awarded).
In October 2023, Luke Farritor won First Letters Prize, a progress prize that required finding at least 10 letters in a 4 cm² area. He used machine learning to find ink patterns. Detected patterns were fed back for training the machine learning model, which thereby learned to detect letters that cannot be recognized with his eyes. In his discovery, papyrologists on the organizing team could immediately recognize a word "porphyras" (First word discovered in unopened Herculaneum scroll by 21yo computer science student). Youssef Nader won a second-place prize for independently finding the same word shortly later.
In February 2024, the Grand Prize was awarded to a team of Youssef Nader, Luke Farritor, and Julian Schilliger. They achieved much more than required for the prize, revealing more than 2000 characters in total.
Still, about 95% of the scroll are yet to be read, and the Vesuvius Challenge offers further prizes for 2024!

Encryption for Security of Satellites

Thousands of satellites are orbiting the Earth. Naturally, they are wirelessly controlled with signals from a terrestrial station. Malicious control signals from an unauthorized entity might result in serious consequences ("Cybersecurity Principles for Space Systems" (2020)). Frequencies used in communication with satellites are not disclosed and messages are encrypted. But hackers might access such information, or might simply hack the ground station (車も衛星もハッキングされる時代！？注目が集まる衛星のサイバーセキュリティ (2021)). There are reported instances of actual hacking of satellites ("Hack a Satellite while it is in orbit" (2007), "AsiaSat accuses Falungong of hacking satellite signals" (2004) cited in Wikipedia).

CCSDS (Consultative Committee for Space Data System), an international standardization body since 1982, has a security work group, which has issued documents such as "Green Book on use of security in CCSDS" and "CCSDS Encryption Algorithms and authentication algorithms" among others (CCSDS Overview by NASA, p.14).
The encryption scheme specified for controlling satellites is, as expected, AES (Advanced Encryption Standard), a symmetric block cipher adopted for the US government in 2001 as a replacement for DES (Data Encryption Standard). The Green Book "CCSDS Cryptographic Algorithms" (2023) prescribes "AES is the sole symmetric encryption algorithm that is recommended for use by all CCSDS missions and ground systems." (The same expression is found at least as early as the 2014 version, but not in a 2012 Blue Book).
What was used before AES was recommended by CCSDS? One might think it was DES, but actually, "at first security was thought of as not required for civilian space missions by CCSDS", according to the 2008 Green Book "Encryption Algorithm Trade Survey". Indeed, one patent document JP 2000-341190 A1 says communication with satellites needs to be encrypted "for artificial satellites for specific purposes." Even today, researchers point out security measures for satellites are no more than "security by obscurity" ("Satellites Are Rife With Basic Security Flaws" (2023)).

Japanese Cipher Machine Green (Not Japanese Enigma)

Japanese cipher machines include RED, ORANGE, PURPLE, JADE, etc. Relatively unknown of the series is GREEN. Some sources say GREEN is a US codename for 3-Shiki Kaejiki (三式換字機), known as the Japanese Enigma, but the picture on the book that seems to be the source of this association shows it is not the GREEN machine as recorded by US cryptanalysts. GREEN is a codename for a cipher machine, 1-Shiki 1-Go Injiki (一式一号印字機), of the Imperial Japanese Army captured at Baguio in the Philippines in May 1945.
I learned all these from Chris Christensen, whose new paper, "The Japanese Green Machine" in Cryptologia is now published online. I believe this is the first detailed account of the real Japanese Green machine.

Dutch Windmill Code?

Windmill Code Used by Dutch Resistance?

Windmills are part of the Dutch landscape. According to Wikipedia, the positions of sails of Dutch windmills were "used to signal the local region during Nazi operations in World War II, such as searches for Jews." If this text (present from the first version of 2 March 2023) was taken from Goleta Valley Historical Society) (present as early as in August 2022), the paragraph break in the latter suggests that the signalling was made by one specific position of the sails. If so, the information conveyed would have been no more than an on/off alarm.
According to Traces of War, the windmill Vrijheid in Beesd "was used in World War II by the resistance to sent messages by the position of the wings. To commemorate this, the hitherto unnamed mill was named "The Freedom (De Vrijheid)" after the renovation in 1968." According to machine translation of the explanation board, the position of the sails was indeed used to pass on information, and the name "de Vrijheid" was given in commemoration of the efforts to regain freedom during the war, but the connection between the passing of information and war-time efforts is not clear. But Wikipedia confirms "During World War II, the mill was used to send signals to the Dutch resistance. This was done by the position that the sails were set at."

Traditional Meaning of Windmill Positions at Rest

At least, it seems certain that the position of the sails of a windmill at rest has been traditionally used to convey some meaning, though there is discrepancy among sources about the specific meaning. According to one source, a position slightly tilted to the left means joy; a position slightly tilted to the right means mourning; a straight position like "+" means a short rest (no operation for a few days); a diagonal position like "x" means a long rest (no operation for weeks), etc. (Olie Molen de Passiebloem). The same image (reproduced below) is posted on many websites (Google).
This form of expression was actually used in some public occasions. Windmills were placed in "mourning position" when many Dutch people were killed in a Malaysian aircraft shot down in 2014 (CNN quoted in Wikipedia) as well as when Prince Friso died in 2013 because of a skiing accident (PresReader, wind mill sign language in Holland).

Long Distance Communication like Optical Telegraphy

Regarding communication more than a simple expression of some meaning, apart from Wikipedia, the magazine Popular Mechanics (June 1908), p.365 (Google) reports the Dutch government's experiment to use windmill signaling for military purposes between mills some miles distant. It says secret code had been used "from generation to generation of millers." (The idea is similar to the optical telegraphy known from the eighteenth century.)

Use by German Agents?

According to Cathleen Small, Code Breakers and Spies of World War II (Google), p.13, during the First World War, German agents used starts/stops of the sails of Dutch windmills to transmit messages in Morse code.

English Ciphers during the Restoration Period

Many English ciphers from the Restoration Period are preserved in TNA SP106/6 and BL Add MS 40677. I uploaded a new article "English Ciphers during the Restoration Period" about these.
Some of these ciphers use printed templates, which are already discussed in another article, which is now a bit supplemented and renamed as "Diplomatic Codes after the Glorious Revolution and Use of Printed Templates".

Preconcerted Code Words Used by Secretary of Mary, Queen of Scots

Mary, Queen of Scots, is known to have used various ciphers, including very simple ones as well as ones with quite a few code symbols. I recently learned Gilbert Curll, her Scottish secretary, also used preconcerted language (code words) such as "the merchant of London" (Queen of England). I added it to "Ciphers of Mary, Queen of Scots".