Now, it’s been some time now….we are all familiar with the word Cryptography. Yeah, you guessed it right. It’s the art of encryption and decryption of data. Cryptography maybe a technology of the 21 century, but its roots are from the medieval period. In fact the Alexander the Great himself used a type of cryptography known as Cypher.
Cryptography or cryptology is derived from a Greek word,
‘crypto’ means ‘hiding’ and graph means ‘writing’ or ‘data’. Therefore the art of
concealing the data or information is called as Cryptography. In terms of computers,
Cryptography is the practice and study of techniques for secure communication in
the presence of third parties. More generally, it is about constructing and analysing
protocols that overcome the influence of third parties and which are related to
various aspects in information security such as data confidentiality, data integrity
and authentication. Modern cryptography intersects the fields of mathematics, computer
science, and electrical engineering.
Cryptography before the modern age was effectively synonymous
with encryption, the conversion of information from a readable state to nonsense.
The originator of an encoded message shared the decoding technique needed to recover
the original information only with intended recipients, thereby forbidding unwanted
persons to do the same. Since World War I
and the advent of the computer, the methods used to carry out cryptology
have become increasingly complex and its application is more far-flung.
Modern cryptography is to a great extent based on mathematical
theory and computer science practice; cryptographic algorithms are designed around
computational hardness assumptions, making such algorithms hard to break in practice
by any adversary. It is theoretically possible to break such a system but it is
infeasible to do so by any known practical means. These schemes are therefore
termed computationally secure; theoretical advances and faster computing technology
require these solutions to be continually adapted. There exist
information-theoretically secure schemes that provably cannot be broken even with
unlimited computing power-an example is the one-time pad -but these schemes are
more difficult to implement than the best theoretically breakable but
computationally secure mechanisms.
The art of protecting information by transforming it into
an unreadable format, called cipher text. Only those who possess a secret key can decipher the message into plain
text . Encrypted messages can sometimes be broken by cryptanalysis, also called
codebreaking, although modern cryptography
techniques are virtually unbreakable.
As the Internet
and other forms of electronic communication become more prevalent,
electronic security is becoming increasingly
important. Cryptography is used to protect e-mail messages, credit card information, and corporate
data. One of the most popular cryptography systems used on the Internet is Pretty Good Privacy because it's effective and free.
Cryptography systems can be broadly classified into
symmetric-key systems that use a single key
that both the sender and recipient have, and public-key systems that use
two keys, a public key known to everyone and a private key that only the recipient
of messages uses.
