43 pages • 1 hour read
Simon SinghThe Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography
Nonfiction | Book | Adult | Published in 1999A modern alternative to SparkNotes and CliffsNotes, SuperSummary offers high-quality Study Guides with detailed chapter summaries and analysis of major themes, characters, and more.
Chapters 5-6Chapter Summaries & Analyses
Chapter 5 Summary: The Language Barrier
With the advent of new communication technology, the Second World War was the first major conflict that depended heavily on the use of intelligence. At the same time, there was an increasing contrast between the kind of intelligence that could be communicated via complex code in the comfort of war rooms and command stations on battleships and what was needed in the heat of battle. As one war correspondent put it, “When the fighting became confined to a small area, everything had to move on a split-second schedule. There was not time for enciphering and deciphering” (261).
In order to solve this problem, a creative solution was found by Philip Johnston: The use of very rare languages could be employed to great effect, specifically the language of the Navajo people who inhabited the reservations in the American southwest: “Fully aware of how impenetrable the language was for those outside the tribe, Johnston was struck by the notion that Navajo, or any other Native American language, could act as a virtually unbreakable code” (261).
After developing the idea and training a company of Navajo code talkers, they put the communication process to the test. They discovered that even with weeks of analysis, their own Navy code breakers could not crack the code. While the Navajo language had to be supplemented by specific military vocabulary that did not exist in their native vocabulary, the use of Navajo as a code worked to splendid effect. Eventually, “there were 420 Navajo code talkers” (272) that saw active combat and contributed to the war effort.
The success of the code talkers demonstrates the curious accident that ancient languages also function very much like codes in modern day analysis if their use and interpretation has been lost to time. The most famous example is the ancient Egyptian system of hieroglyphics: “The earliest hieroglyphics date back to 3000 B.C., and this form of ornate writing endured for the next three and a half thousand years” (274). Taken from the Greek, meaning “holy carvings/markings,” the hieroglyphics that adorned Egyptian architectural marvels stumped historians and linguists for centuries. Eventually, the characters of the hieroglyphic system were discovered to be representative of phonetic characters; the assumption had been that this would have been too advanced a system for that time period, but this was proven false thanks to the Rosetta Stone.
Found in an ancient wall in the Nile Delta, the Rosetta Stone contains writing in three parallel languages—ancient Greek, Egyptian demotic, and Egyptian hieroglyphics—and was quickly used to begin deciphering the meaning of ancient Egyptian literature. Thomas Young, an English savant and linguistic expert, made the connection between hieroglyphics and the characters used in Chinese writing, both representing sounds (and not vocabulary words, as had been previously assumed, as a form of picture writing).
The discovery of how to decipher and read Egyptian hieroglyphics led to other major discoveries as well, such as the famed “linear B…a Cretan script dating back to the Bronze Age” (294). While all attempts had failed, it was left to a professor of Classics at Brooklyn College, Alice Kober, and English architect, Michael Ventris, to crack the code of Linear B. They gathered enough evidence to suggest that it was a written form of a pre-Hellenic form of ancient Greek, and the linguist John Chadwick, a researcher at Cambridge, put the final touches on the theory by affirming that their findings matched up with his own research into the roots of the first forms of ancient Greek.
Chapter 6 Summary: Alice and Bob Go Public
In developing technology to decipher ever-more complex messages, the Allied forces during the Second World War developed a deciphering machine they called “Colossus,” specifically designed to help with deciphering the messages sent between the new German Lorenz cipher machines that Nazi high command used to communicate.
This was a new challenge, as “[b]reaking the Lorenz cipher required a mixture of searching, matching, statistical analysis and careful judgment, all of which was beyond the technical abilities of the [Turing] bombes” (326). The most important and innovative aspect of the Colossus was the ability to program it; it served, in fact, as “the precursor to the modern digital computer” (327). Unfortunately, the blueprints for the machine were destroyed in the post-war climate of hiding all information related to secret service and espionage.
By this point, however, the die was cast: Digital computation was a reality that had begun to encroach into contemporary life. In the proliferation of digital computation technology, and the communication required for its use, government agencies got involved in determining what kind of encryption would be allowed in commercial applications. Standards were introduced, but even with the introduction of certain standards, encryption and subsequent deciphering of encrypted information became a big business. The most prevalent obstacle in the process became what is called “key distribution.”
When a cipher is employed, the sender uses it to encrypt their message, but the recipient needs the algorithm in order to decipher the message—this is called the “key.” So, the problem becomes this: How does the sender get the key to the recipient securely, without it being discovered or made public? The key needs to be kept secret, just like the message; otherwise, any messages sent with that encryption technology will be open to the public: “In short, before two people can exchange a secret (an encrypted message) they must already share a secret (the key)” (343). In thinking over the problem, a trio of stock characters came to represent the various parts of the problem: “When thinking about the problem of key distribution, it is helpful to consider Alice, Bob and Eve, three fictional characters who have become the industry standard for discussions about cryptography” (344).
Certain methods of distributing keys were developed, but the search for greater ease and security progressed. One such system was the padlock system, illustrated by the comparison to a message secured with padlocks: Alice can send Bob a message in a locked box, which he then returns with a second lock—his own. When Alice receives the box back, she removes her own lock and sends it back to Bob, who can then finally unlock the box that is secured with only one lock at this point: the lock that he put on the box, and for which he has the key.
In this way, a physical message can be sent and easily secured. The obstacle was how to implement this system of logic digitally for messages and interactions on computers and via the internet. What came to be the gold standard in this area was known as an “asymmetric cipher,” where the mode of encryption is secret, but the mode of decryption is public. This creates a distinction between private keys and public keys: Someone could use a recipient’s public key to encrypt a message to them, and the private key that only the recipient holds can unlock the message created with that public key.
Referring back to the padlock metaphor, this manner of encryption is like creating a unique lock/key combination where there is only one key, but many locks are created that can be opened with that one key. Anyone can send a locked box to Alice with her publicly available padlock design, but since she has the only key, all the messages sent via that lockbox would be private. In the digital world, the asymmetric key invented in this mode came to be known as RSA (named after the three men who made the discovery).
Chapters 5-6 Analysis
Chapter 5 takes the overall book topic and launches into a closely related tangent of codes and ciphers: languages, both living and dead. Some ancient languages are not used as everyday languages with which to communicate but are still widely known, read, and used in specific cases. Latin, for instance, is likely the best example of this phenomena. Latin is no longer spoken and used like a modern language, and so in this sense it might be considered a dead language (a moniker used for ancient languages that are not used anymore).
However, millions of people today know and use Latin regularly thanks to other circumstances. Classicists know and read Latin fluently thanks to their research interests, and many of the greatest works of the Western literary canon are those originally composed in Latin. At the same time, Latin quickly became the official language of the Christian Church in the fourth and fifth centuries; it remains the official language of the Catholic Church to this day, used for all official teaching and documents.
Other ancient languages, however, are lost to the ravages of time and history. Many are simply forgotten and unknown, but some have been rediscovered but without any knowledge of how to read them. The hieroglyphics that had once been used in ancient Egypt had obviously once been used as the literary form of the Egyptians’ spoken language, but there remained no way to actually discover how to read them. It took the discovery of the Rosetta Stone for this to occur. Since archeologists and historians already knew how to interpret ancient Greek, the portion of the stone that contained Greek acted like a crib sheet for deciphering the unknown carvings of the Egyptian language.
The employment of native Navajo speakers during the Second World War took advantage of this exact dynamic in order to create and implement a secret code language that nobody outside an extremely small, select group could understand. Thanks to the fact that the Navajo language has no ties to any Indo-European language, there was absolutely no way to make headway into deciphering the Navajo language from any previously known language. When the war was over, the Navajo code talkers were as well-known as their language, which is to say, not at all. The secrecy required for all covert operations and intelligence agencies/activities meant that their contributions were kept secret for decades until enough time had passed where their efforts—along with that of countless others—could be made available to the public.
In addition to the classified status of the codes themselves, the invention and existence of the various machinery built and used to crack the various codes during wartime was also a well-kept secret. In some instances, it was well kept because the information was actually destroyed. The blueprints for the Colossus decryption machine, for instance, were destroyed in an effort to keep its existence a secret so as to not give any information to enemy forces. While Colossus was only one of many such instances, it remains a good example for a phenomenon that necessarily accompanies the work done by those involved in official espionage efforts: The public can never know about the work they do, so their efforts almost always go unrecognized and unrewarded.
While the Colossus served as the first instance of a digitally programmable computer system, it was left to others to reinvent the technology in a non-military context. As a consequence of the digital computer’s invention in a civilian/commercial context, however, it could be implemented in a way that allowed public applications of encryption technology to begin developing and spreading.
Now that computer technology was widely and publicly available, the creation of encryption technology entered a completely new era. Rather than being at the mercy of particular government agencies staffed by a few dozen hand-selected members, the best and brightest the world had to offer could try their hand at encryption/decryption technology simply by being interested and applying themselves. With the public dissemination of this information, encryption became the subject of enthusiasts, hobbyists, and professionals alike. In the marketplace of ideas, where the best idea wins, new heights began to be achieved in record time.
