Enigma Cipher Machine the German

Enigma Cipher Machine

The German Enigma machine is currently one of the most interesting aspects of World War II. The machine was created on principles that proved nearly impossible to break. This was only nearly impossible in the end, as initially Polish and later French and British code breakers were able to use the machine's shortcomings against it (Lycett). Also interesting is the fact that the German forces appeared oblivious of these successes to the extent that they ascribed their significant losses to other developments and technologies. The document describes the background and history of the Enigma machine, as well as some of its operation principles and breaking the codes it created.

Introduction

The stormy environment of the World Wars was criss-crossed with many encrypted messages and false leads. These were to help the various sides protect their plans and secrets relating to the war. World War I and II were however preceded by a significant history of cryptography, which was applied to many purposes other than warfare. One of the most prominent and puzzling machines used during World War II also had its origins in prewar days.

The appropriately named Enigma machine was one of the manifestations in reaction to the rise of wireless communication during the early 1900's (Rijmenants). Wireless communication necessitated more secure communications not only for military, but also for civilian use. The basis of the Enigma machine was pioneered by an American, Edward Hugh Hebern. Hebern developed a cipher device with rotating disks. Arthur Scherbius, building upon similar work, patented a machine that used rotors. This resulted in the first commercialization of the Enigma a cipher machine in 1925 (Carlson).

Background and History

Enigma a, a large, cumbersome machine, was soon followed by the Enigma B, which was more or less the same thing. Because of their bulky nature, these machines were both unattractive and impractical for military use. This was remedied by developing a reflector, making possible a much lighter and more compact Enigma C. The typewriter that formed so much of the bulk and weight in the first two Enigmas was replaced by a lamp panel. Enigma D. And its successors, the accumulation of years of research and development, were finally introduced commercially and sold successfully to both military and civilian institutions all over Europe by 1927 (Cooper).

According to Rijmenants, Enigma K. was used by the Swiss army, Enigma D. By the Italian Navy and Spain, while Japan used the adapted K. version, which was Enigma T. On the basis of these, Japan developed a version with horizontal rotors. Interestingly, the codes of all these machines were successfully broken.

A turning point for the Enigma came when the German Navy purchased the commercial Enigma D. during 1926. The machine was adapted for military use and renamed to Funkschlussel C. Advances include a system of gears, and a rotating reflector and counter. This led to the Enigma G, with different rotors and a pin placement on the right counter. The German Secret Service bought this version, weighing only 12 Kg, in 1928.

According to Rijmenants, the Enigma D. also saw parallel developments in the German

Wehrmacht (Army). The Enigma I for example included a plug board as revision, and became known as the Wehrmacht Enigma. Initially equipped with three rotors, the later versions from 1939, included five rotors. In 1934, the German Navy also used the Wehrmacht model for the advantage of its secure plug board, and added further rotors to bring the total to eight. Finally, the M4 four rotor model was introduced during 1942 (Rijmenants).

The reason for the rising German interest in the Enigma machine after the military's initial disinterest did not lie only in the fact that the newer Enigma versions were lighter and more practical. Indeed, this interest also arose from an increasing realization of the need to more securely encrypt their messages in the wake of World War I. During the First World War, the German Army became aware that the British were successfully deciphered their secret messages. The German answer to this unacceptable state of affairs was the Enigma machine, soon to become one of the greatest military headaches of both World Wars. Despite assertions to the contrary, time would prove that even the newest and most cryptic codes from these machines were not unbreakable.

Deciphering the Enigma

Attempting a machine that would make codes impossible to break, the German military, as seen above, made a number of modifications to their Enigma machines. The plug board for example enabled the machine to increase its number of possible cipher starting points to something between two and three billion. The Enigma's rotors were also interchangeable while being wired differently, adding even more protection and encryption. In order to decipher codes created in this way, the code breaker would need to know not only the positions of each rotor, but also each starting position. Incredibly, according to Cooper, 100 machines working 24 hours per day would take 5.8 years to exhaust all the possibilities created in this way. It was therefore impossible to decipher the codes without the actual machine, the cipher key, and the correct rotor placements.

Nevertheless, there were those who attempted the impossible, and eventually succeeded, because the Enigma machine was not as flawless as the German officials believed it at first. The first attempts at deciphering the codes emerged from Poland's Cipher Bureau during 1932. According to Rijmenants, Marian Rejewski, Henryk Zyglaski and Jerzy Rozicki used two major security flaws - the "Achilles heel" of the Enigma - to eventually attain success. These are the global ground setting and the twice encoded message key - the latter was implemented to exclude possible errors from encrypted messages. The initial success was however short lived, and elements such as increased sophistication, new procedures, and lack of funds defeated the Polish effort by 1939. Poland succumbed to German invasion, but their initial efforts survived to reach French an British shores.

The Government Code and Cipher School from the United Kingdom built upon the Polish work to break the Enigma code initially by hand and later by increasingly complicated deciphering machines (Rijmenants). These were developed by Alan Turing and Gordon Welchman, who many credit with winning the war as a result of their deciphering efforts. In short, the Turing machine searched for given pieces of plain and cipher text, which were then used to identify the key settings that served as the basis for deciphering the rest of each message.

Extraordinary measures were taken to keep the German forces from suspecting that their ciphers might be compromised.

It is interesting that these measures were so well camoflaged that, even when heavy U-boat and crew losses occurred as a result of the deciphering efforts, the German forces attributed these to technologies such as sonar systems, boat detection planes, and destroyers. Meanwhile, the British were intercepting more or less the entire German communication system via "Y-stations," and deciphered with the help of more than 7, 000 workers at Bletchley Park. With the deciphered messages helping the Allies to intercept U-boats and steal encryption documents and machinery, all improvements the Germans attempted to make to the Enigma were successfully thwarted.