The Chaocipher Clearing House

What's New?

Moshe Rubin (

I began this website update history in October 2009.  The purpose is to enable returning visitors to easily track new changes and discover the latest additions.  Be sure to use your browser's 'Refresh' button to view the latest version of this page.

DatePageLinkUpdate Description
23 October 09TCCH homepagexAdded link to J. F. Byrne chronology
24 October 09Historical CorrespondencesxAdded link to 6 February 1957 letter from WFF to JFB
30 October 09Progress Report #14x
31 October 09Progress Report #14xAdded Mike Cowan's opinion regarding the significance or insignificance of no intervals less than 9.
19 November 09List of pt/ct indentities in Exhibit 1xFour intervals were not sorted by offset.
20 November 09Information about Henry E. LangenxTwo articles from the American Cryptogram Association's periodical "The Cryptogram": a biography when he became editor in 1952, and an obituary in 1962.
18 December 2009Progress Report #11xMike Cowan correctly pointed out an error in the analysis that ruled out a C98 MM2 model with steps of 1/1/2/4.  The error and correction are now noted on the page.  The result that this model is ruled out remains unchanged even after the corrections.
29 March 2010Progress Report #15xInitial uploading.
1 June 2010Progress Report #16xThe National Cryptologic Museum Foundation (NCMF) acquires the Chaocipher machine and papers
2 July 2010Progress Report #17xChaocipher revealed: the actual algorithm is described publicly for the first time.
8 August 2010Progress Report #18xUploaded a paper providing an in-depth analysis of Exhibit 1 found in Byrne's "Silent Years".
19 November 2010Progress Report #19xUploaded Jeff Calof's paper ""Silent Years" - Chapter 21 (Chaocipher) Examined: Analyzing Byrne’s Assertions".
18 December 2010Progress Report #20xMike Cowan submits a new paper: "Chaocipher: Solving Exhibits 1 and 4"
1 April 2011Historical CorrespondencesxAdded original Hitt-Byrne letter corresponding to the quotes brought in Silent Years, page 273.
7 April 2011Information about Henry E. LangenxHenry E. Langen's complete notes and summary of all his dealings with John F. Byrne and Chaocipher.
27 April 2012Progress Report #21xChaocipher paper published in Cryptologia, Patricia Byrne passes away at 92
18 January 2013Progress Report #21xUpdated the page to note that the Chaocipher article in Cryptologia can now be downloaded for free.

Copyright (c) 2009-2013 Moshe Rubin
Created: 23 October 2009
Updated: 18 January 2013

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