National Cryptologic Museum Library
The National Cryptologic Museum hosts thousands of publications including historic books, articles, and magazines. This catalog lists all the holdings.
Rare Book Collection
The Museum's rare book collection includes books believed to have been acquired during the 1930s by the small group of individuals who worked for William Friedman. The books are not codebooks but are texts that elaborate on the science of cryptography. The collection includes an extremely rare copy of the first book ever written in the Western world on the subject of cryptology, Polygraphiae by Johannes Trithemius, published in 1518. Other books in the Museum collection date back to the 16th century as well and many include notes made in the margins by the students using them in the 20th century.
September 11th Memorial
In silent tribute to the more than 3,000 innocent people killed during the three separate terrorist attacks on September 11, 2001, a scorched 12" x 17" concrete remnant of the outer wall of the Pentagon is exhibited in the Memorial Hall area of the Museum. Surrounding the remnant are four statements by President George W. Bush on America's resolve to win the War on Terrorism. They are:
"We will not tire, we will not falter, and we will not fail." 9-20-01
"We will come together to strengthen our national intelligence capabilities to know the plans of the terrorists before they act." 9-20-01
"Some victories will be won outside of public view, in tragedies avoided and threats eliminated." 9-29-01
"None of us will ever forget this day. Yet, we go forward to defend freedom and all that is good and just in our world." 9-11-01
Vietnam War
This Museum exhibit displays an example of the cryptologic support provided during the Vietnam War. Numerous fixed field sites in Vietnam conducted both strategic and tactical collection missions and radio direction finding (DF). Throughout the war, all military services' cryptologic elements took part in providing tactical and strategic information to military commanders. The Army Security Agency used a wide variety of aircraft as well to conduct aerial reconnaissance missions. The U.S. Navy also began its surveillance as early as 1962, conducting shore, shipborne, and aerial reconnaissance. Information derived from signals and electronic intelligence flowed quickly back to the commanders in the field. National Security Agency civilians worked side by side with their military counterparts and the South Vietnamese. Those stationed at NSA in the United States worked around-the-clock processing, translating, and forwarding this vital intelligence.
Women in American Cryptology (Creating a Legacy)
The exhibit highlights the contributions of 24 women who have helped create cryptologic history. The display begins with a member of the Culper Spy Ring during the American Revolution who used her laundry as a secret code. Women spies from the Civil War also used codes and ciphers to aid those fighting for the causes they believed in. But it wasn't until the twentieth century that women began to work full-time in cryptology. During WWI, several women considered to cryptologic pioneers began their careers, as did some women few people today would know. During WWII, thousands of women joined the military or worked as civilians for the military as cryptanalysts, intercept operators, technicians, machinists and every other position available in cryptology. Many of those women chose to stay in the field after the war providing breakthroughs and contributions throughout the Cold War. Eventually, women rose to the highest ranks of management and today continue to support, develop, and build the cryptologic legacy of tomorrow.
World War 1: American Black Chamber
This Museum exhibit details the checkered career of Herbert O. Yardley (1889–1958), who headed the highly secret MI-8, or the "Black Chamber." Yardley began his career as a code clerk with the U.S. State Department, and during that service discovered his natural talent as a cryptanalyst. During World War I, Yardley served in the cryptologic section of Military Intelligence (MI) with the American Expeditionary Forces. After the war, Yardley lead the first peacetime cryptanalytic organization in the United States, MI-8. MI-8 had an early success: in 1921–22, Yardley and his staff solved the cipher system used by Japanese negotiators at the Washington Naval Conference. In 1929, the State Department closed down MI-8. To earn money, Yardley wrote The American Black Chamber, which revealed to the world the work of MI-8. It became an international best seller. However, it angered the American government and jeopardized cryptologic activities.
World War 1: Radio Intercept Site
This site is a mock-up of the World War I intercept site in Souilly, France. The exhibit is based on two pictures of the original shack. Intercepting the enemy's radio communication was imperative for success during WWI. At the outbreak of war in August 1914, the German Army successfully used vital radio intercepts, enabling them to defeat the Russian 2nd Army in the Battle of Tannenberg. Soon all the major participants in World War I would go on to use more encompassing communications intelligence (COMINT) with varying degrees of success. Although signals intelligence was in its infancy, and radio was the new communications technology, the U.S. Army's Radio Intelligence Section used their newfound capabilities to "spy" on enemy conversation. Signals could be intercepted without being in close proximity to the transmitter or transmission lines and could provide vital information about enemy tactics and strategy.
World War 1: Zimmermann Telegram
The Museum exhibit highlights how one decoded message changed the course of history during World War I. The Germans planned to cut off supply lines to Britain and France by beginning unrestricted submarine warfare in the Atlantic. Fearing the United States would join the battle if their ships were sunk, Germany asked Mexico to start a war with the United States and promised the return of Texas, Arizona, and New Mexico. The request was sent from the foreign minister in Berlin, Arthur Zimmermann, through the German ambassador in Washington, D.C., to the German ambassador in Mexico City, in the form of a coded message. It became known as "The Zimmermann Telegram." Britain intercepted the message as it was transmitted overseas. Royal Navy cryptanalysts decoded and showed the message to the United States. Ultimately, Congress declared war on Germany. Thus, a single coded message, and the efforts of cryptanalysts, changed history.
World War 2: Battle of Midway
This Museum exhibit displays The Battle of Midway, which is frequently referred to as "the turning point in the Pacific." In June 1942, the Japanese had hoped to surprise the American military on Midway Island and claim this crucial location. However, American Navy cryptologists stationed in Hawaii had made some breaks into the Japanese Navy Fleet Code, known to cryptanalysts as JN-25B. Knowing Midway would be attacked, the U.S. Navy and Marines were able to adjust their forces and combat the attack head on. After a series of losses, the United States won a decisive victory over the Japanese Imperial fleet. Damages to the Japanese carrier fleet were insurmountable and their momentum was broken. The Japanese were never able to replace the four aircraft carriers and 332 aircraft they lost in the battle.
SIGABA/ECM
The U.S. Army's SIGABA, called the ECM (Electric Cipher Machine) in the Navy, was the only machine system used during World War II to remain completely unbroken by an enemy. The Germans referred to the U.S. machine, SIGABA, as the 'Big' machine. It utilized the same principle of rotating, removable, wired rotor wheels that the German Enigma employed. However, unlike the stepping motion of the Enigma, the SIGABA/ECM's motion appeared to be random. It wasn't, but it was so complicated, the German's never broke it, and the Japanese gave up trying. Frank Rowlett of the Army's Signal Intelligence Service developed the complicated stepping motion.
Tunny and Sturgeon
The Tunny and Sturgeon machines (referred to as the "Fish" machines) were on-line cipher machines. Messages could be simultaneously enciphered and transmitted, saving a great deal of time. The Tunny (which is British slang for Tuna) was a German Army machine that could be used out of the back of a truck or at a fixed site. To create its encryption, the Tunny used the international telegraphic "Baudot" cipher and an additive placed on the cipher by the rotors. It was used to stream high-level teleprinter messages. The British built the first large valve programmable computer, Colossus, to decrypt Tunny messages, cutting decrypt time from weeks to hours. The Sturgeon was primarily a German Air Force system. It was capable of high-speed teleprinter transmissions. This particular machine used cable rather than radio to transmit its messages, thus decreasing the Allies' ability to intercept. A Swedish mathematician, Arne Beurling, was the first to break the Sturgeon, a feat he accomplished in just two weeks.
Jade and Purple
Intended for high-level encryption, the Japanese family of machines using telephone selector switches came to be known in the United States by their 'color' code names: Coral, Jade, and Purple. The switches performed the same function as a wired rotor, stepping forward through each of the 25 contacts. However, unlike wired rotors, the switches could not be taken out and rearranged, a serious limitation to the system. The Japanese Imperial Navy used the Jade machines for its high-level encryption of the katakana syllabary. The Japanese diplomatic system, code named Purple, differed from Jade in that it included a plug board.
Also, on display is the Army's first analog machine used to decrypt Purple enciphered messages. This machine solved the famous 14-part message telling the Japanese ambassador to break relations with the United States on December 7, 1941, at 1:00 p.m.
World War 2: Native American Code Talkers
This exhibit displays the critical work of Native American Code Talkers during World War I and World War II. Having suffered losses in the First World War as a result of the Germans listening to U.S. communications, a company commander of the U.S. Army's 142nd Infantry Regiment found a solution. Captain Lawrence overheard two Choctaws speaking in their own language. He arranged for them to become radio communicators. They used common words to replace military terms and spoke Choctaw, thus becoming the first Code Talkers. On October 26, 1918, in northern France's Argonne Forest, the Choctaws' communications resulted in a completely successful surprise attack against the Germans. The Army continued the program and during World War II recruited Comanches, Choctaws, Kiowas, Winnebagos, Seminoles, Navajos, Hopis, Cherokees, and others. The Marine Corps took the Army work and codified, expanded, refined, and perfected it into a true security discipline, using Navajos exclusively.
World War 2: Enigma
This exhibit showcases possibly the most well-known of all cipher machines — German Enigma. It became the workhorse of the German military services, used to encrypt tens of thousands of tactical messages throughout World War II. The number of mathematical permutations for every keystroke is astronomical. Allied forces were able to read most of the Enigma encrypted messages throughout most of the war as a result of the tireless effort of many Allied cryptologists. It is an electromechanical machine that used a combination of wired rotors and plugs to change each letter as it is typed. Today, many historians believe that the Allies' ability to read the Enigma-enciphered messages and act on that information shortened the war by as many as two years, saving thousands, if not millions, of Allied and Axis lives.
SIGSALY
The exhibit is a mock-up of one-third of the entire SIGSALY system, which weighed 55 tons and consisted of 40 racks of equipment. SIGSALY was the first secure voice encryption system for telephones. It was invented and built by Bell Telephone Laboratories in 1943. It had several technological "firsts" including pulse code modulation for speech transmission, multilevel frequency shift keying, and bandwidth compression. It took 13 people to operate and required 15 minutes to set up a phone call.
World War 2: U.S. Navy Cryptanalytic Bombe
The U.S. Navy's Cryptanalytic Bombe is the culmination of years of work and the efforts of mathematicians and engineers from Poland, England, and the United States. It was the solution to the problem of Germany's World War II 4-rotor cipher machine Enigma, and it led to the Allies' successes in the battle of the Atlantic and the war in Europe. In 1942 a fourth rotor was added to the U-boat Enigmas and the original British Bombes, designed to solve the three-rotor Enigmas, were not able to find solutions to those messages. WAVES (Women Accepted for Volunteer Emergency Service) were inducted into the U.S. Navy and built and operated the Bombes, working 24 hours a day, 7 days a week. They set the machines up and tested the results. The U.S. Navy Bombes rapidly searched the hundreds of thousands of possible settings on one wheel order of a four-rotor Enigma. (The German Navy had eight wired rotors from which to select three that went into the Enigmas. The fourth rotor remained in its position.) The Navy Bombes, and those who built and operated them, played a crucial role in saving Allied and Axis lives and hastened the end of the war in the Atlantic and Europe.
Danish Device
The Beyer pocket cryptologic device from the 1930s resembles the size and appearance a pocket watch of the era. Only about a half-dozen examples of the Beyer device are known to exist. The Beyer device consists of two disks, or rings carrying two dials divided into 26 or 30 slots in which the alphabet is written — alphabetically or other. The possibility of decoding messages encrypted on the Krypto device is extremely small since there are 7034 × 1061 combinations.
Hebern Device
The machine was designed by Edward Hebern to encipher and decipher typed messages. It used several rotors with 26 letters to encrypt messaging similar to other World War II devices. Hebern designed the device through his company, Hebern Electric Code, but it was never used by the U.S. government due to weaknesses discovered by William F. Friedman.
CSP-845
The CSP-845 was the U.S. Navy's version of a strip cipher system, which played an important role in classified communications before and during World War II. At the beginning of the war, a great deal of reliance was placed on strip systems due to the shortage of cipher machines. It is a hinged aluminum board (14" × 12") into which there are 30 milled grooved channels designed to hold changeable paper strips containing random mixed alphabets. The method of operation changed several times during the war to improve the security of the system.
ADONIS (KL-7)
This device replaced the Sigaba and was developed in 1952. It was used for Secret-level communications and by NATO troops for interoperability with U.S. forces. The device has eight rotors with seven rotors moving in an irregular pattern. It was one of the early machines that had to meet ruggedness requirements. It also used a new technique for "on-the-fly" printing. The print hammer struck the paper while it was still rotating, but the type was still clear. The methodology was later used commercially.
NESTOR (KY-38)
This device is a family of encryption devices based on transistor technology for secure voice communications. The device could be included in a manpack for portability. Designed for the Vietnam War (and rapidly deployed), it was used well into the 1980s. The airborne version included an internal shock sensor. If the plane crashed (or sometimes even with a hard landing) the sensor triggered and reset all the keys back to zero preventing the daily key from falling into enemy hands.
VINSON (KY-57)
This device provided secure radio communications through scrambling and was the follow-on to the NESTOR (KY-38). The device was used by U.S. and allied military and law enforcement. The descrambling keys were distributed on paper tape and loaded into the key tape readers. The device provided tactical secure voice and data on UHF and VHF line of sight, UHF SATCOM networks and tactical phone systems. When a key was turned, communications switched from unclassified to classified. It was replaced in 1993.
FALCON III
The device provided secure connections, (voice, video, data) between the military servicemembers forward deployed in the field and the upper echelons back at the command. The servicemen and women in the trenches would use this device to relay information to the headquarters command rapidly and receive orders back just as quickly. This device ensured that the commanders are able to make informed decisions for quick action. It also gave the service members access to computer information and search engines in remote areas. The FALCON uses standard Internet Protocol but in a highly secure way with easy transport. The integrated device is ruggedized and can be set up quickly for secured communications for U.S. and coalition partners.
KGR-29
This device is used for command authentication and decryption of space communications, typically within satellites. It was NSA's first try to meet NASA's size, weight, and power (SWAP) restrictions by introducing integrated circuit technology. It was employed very early on (1968). In the early days the Air Force was having a problem with the Satellite Control Facility (SCF). Each Satellite Program Office built satellites using their own frequencies, modulation, and data formats. This caused the SCF to install unique ground hardware and software to support each program. To solve this problem, the Air Force started to standardize the communications interface from the ground stations to all their satellites. NSA assisted the U.S. Air Force by developing "Security Modules" for these communications links. Thus began the development of the KG-29 systems.
KG-57
This device was developed to replace the KGR-29 for space communications. It began development in 1975 and was used until 1995. It reduced the size, weight, and power consumption even more than the KGR-29 for satellite communications security equipment, making it the smallest produced encryption devices for satellites. It was finally replaced in 1994 by the NSA-developed ASIC (Application Specific Integrated Circuit) that are used on satellites command and authentication systems today.
KG-46
This device is an encryptor/decryptor for ground and space communications developed in the early 1970s. The KG-46 encrypts plaintext digital data for transmission from space to a ground station and deciphered digital cipher data received from the ground station for use on the spacecraft. This particular one never made it into space having been destroyed when the Titan-34D missile exploded at launch.