Cryptography: The art of keeping the data safe

Keeping information secure is paramount in today’s connected world. Towards this end governments and businesses worldwide view cryptography as a key protective tool to secure critical data and networks.

Simply put cryptography is the science of protecting information by transforming it into a secure format using an algorithm. The objective is to ensure that the message being transmitted is inaccessible or unreadable for unauthorized recipients.

History and evolution of cryptography

Development of computers and progress in the computing world has contributed to the advancements in cryptography.

Modern-day cryptographers have English mathematician, philosopher, inventor and mechanical engineer, Charles Babbage to thank for his pioneering work in the field of cryptography. Babbage is credited with inventing the first mechanical computer, the Difference Engine, which led to more complex electronic designs.

Curiously, German army during World War II used the electromechanical Enigma machine to encrypt messages. In another part of the world Alan Mathison Turing, an English mathematician, computer scientist, logician, and cryptanalyst, developed a similar machine to break the code. Turing played a pivotal role in formalisation of the concepts of the algorithm with the Turing machine.

Ever since advancing cryptography techniques have revolutionized how the world communicates securely.

Connected world and the need for cryptography

A vast amount of crucial personal, government and corporate data passes through various communication channels and is vulnerable to theft and change. Securing digital data with cryptography tops organizations’ agenda. Using the science of cryptography, governments, organisations, and businesses transform critical and secret data into formats that cannot be recognized by unauthorized users.

How does cryptography work?

Using cryptography, a set of readable information-data (plaintext) is changed using an algorithm, or series of mathematical operations to an unidentifiable form. To those who are not authorized to see and access this piece of information, the message being transferred looks like gibberish or what’s technically known as ciphertext.

Major use cases of cryptography

Cryptography has a wide use case and is deployed across industries such as banking, computing, engineering, and e-commerce. Governments and defence forces too use cryptography extensively to carry out research activities/projects and secretive operations. Network security is another big area where cryptography is used extensively.

Key safety features offered by cryptography

Cryptography offers several advantages. Some of these are:

Confidentiality and integrity: Information being transmitted cannot be deciphered by an unintended recipient. Information-data being transferred cannot be altered.

Authentication: Both sender and receiver are in a position to confirm the nature of information being shared between the two.

Non-repudiation: Sender communicating using cryptography cannot deny her role and intentions in the transmission of the information later on.

Types of cryptography

Organisations are largely using three types of cryptographic techniques. These are:

1. Symmetric-key cryptography

2. Hash functions

3. Public-key cryptography

Symmetric-key cryptography: A single key characterizes this cryptography technique where both the sender and receiver of the message share a single key. The sender uses the key to encrypt the plaintext and sends the ciphertext to the receiver. The receiver on the other end applies the same key to decrypt the message for recovering the plain text.

Public-key cryptography: Two related keys (public and private key) are used in public-key cryptography technique. The public key is freely distributed, however, the paired private key, remains a secret. The public key is used for encryption and the private key is used for decryption.

Hash Functions: It is an algorithm sans a key. Using hash functions a fixed-length hash value is computed according to the plain text making it impossible for the contents of the plain text to be recovered. The algorithm is used to encrypt passwords.

Present-day cryptographers have a rich legacy to build on and create a stronger cryptography universe helping mankind connect and communicate securely.