In Rome, Julius Caesar used a system of
encryption where he replaced a character
of the Roman alphabet with the character three positions ahead. Leon Battista
Alberti, “The Father of Western Cryptology”,
introduced a system in which two copper disks with the alphabet inscribed in
it were used. These disks fitted into each
other and the settings of the encryption
could be changed by rotating them.
Major changes have happened in history
due to the use of cryptography and codebreaking. The most interesting one of all
was the breaking of the Enigma machine
which was considered unbreakable.
The Enigma machine was developed by
the German engineer, Arthur Scherbius in
1923 as a secure communication method
British Bombe • Source: www.decodedscience.com [Bletchley Park Trust/SSPL]
the
unbreakable
Enigma
References
for commercial companies. A message
However,
could be typed into the machine and
machine of the Germans was finally bro-
1. Cobb, M. ,Bauchle, R. ,Hazen, F. , Lund,
using three or five rotors which displayed
ken and cryptanalysis was the main rea-
J. ,Oakley, G. , and Rundatz, F. (November
letters of the alphabet, the message was
son for an early Allied victory in World
2014). Encryption. Available at: Techtarget
encrypted into a secret code. During the
War II.
Website. http://searchsecurity.techtarget.
com/definition/encryption (accessed 30th
Second World War, the German army used
the Enigma machine to convert their mes-
In the modern era, cryptography is used
July 2015).
sages to codes and send it through radio
for electronic security. Protecting e-mails,
2. Lycett, A. (n.d.). More information about:
signals to their troops out in battle. These
internet security, computer passwords,
Enigma. Available at: BBC website. <
codes were again fed into the Enigma and
electronic commerce and protecting cor-
http://www.bbc.co.uk/history/topics/enig-
decrypted at the receiving end. Even if a
porate data are some of its applications.
ma> (accessed 30th July 2015).
third party possessed an Enigma machine,
Cryptographers always try to protect
the exact settings of it has to be known to
information and cryptanalysts try to break
decode the message. As the war was at its
these cryptosystems. Thus, with the devel-
peak the Germans changed the settings
opment of technology, it is crucial to
of the Enigma, sometimes several times
introduce advanced techniques of cryp-
a day.
tography because the codes that were
assumed to be unbreakable once have
The Enigma machine was beaten by anoth-
been broken by the fascinating combina-
er machine called the “British Bombe”
tion of mathematics and computer sci-
which was used to decide the settings of
ence.
the Enigma rotors. This was invented by
the mathematician Alan Turing in 1939.
For the invention of the Bombe, the
hardware of the Enigma had to be known.
WASUNDARA JAYAWARDANA
Traffic analysis was also used to predict
Electrical and Electronic Engineering
some text of the encrypted message and
(Third Year)
decide the settings used to decrypt the
code at a high speed.
Gauge Newsletter
University of Peradeniya
33