Cryptography and its applications to Cybersecurity are vital as the world becomes increasingly digital, and the need for security has become ever more imperative. Essentially, the word Cryptography refers to the study of secure communications techniques. Still, Cryptography is closely associated with encryption, or the act of scrambling ordinary text into what’s known as ciphertext.

Then, it returns to ordinary text (called plaintext) when it arrives at its destination. Several historical figures have been credited with creating and using cryptography through the centuries, from Greek historian Polybios and French diplomat Blaise de Vigenère to Roman Emperor Julius Caesar—who is credited with using one of the first modern ciphers—together with Arthur Scherbius.

It’s worth noting that Scherbius created the Enigma code-breaking machine during World War Two. Likely, none of them would recognize the ciphers of the 21^st century. Regarding Quantum Computing and the Threat to Card Payment using Cryptography, the ECSG previously published this follow-up article. It considers the developments made by the card payment cryptographic community.

For example, cryptography creates various encryption protocols regularly used to protect data. These include 128-bit or 256-bit encryption, Secure Sockets Layer (SSL), and Transport Layer Security (TLS). These encryption protocols protect all digital information and data, from passwords and emails to ecommerce and banking transactions. So, what is the role of Cryptography in security?

Understanding What Cryptography Means In Secure Communications Technology

Cryptography is the technique of obfuscating or coding data. It ensures that only the person who is meant to see the information–and has the key to break the code–can read it. The word is a hybrid of two Greek words: “kryptós,” which means hidden, and “graphein,” which means to write. Thus, it translates to hidden writing, but in reality, the practice involves the secure transmission of information.

Cryptography can be traced to the ancient Egyptians and their creative use of hieroglyphics. However, the art of coding has seen great strides over the millennia, and modern cryptography combines advanced computer technology, engineering, and maths—among other disciplines—to create highly sophisticated and secure algorithms and ciphers to protect sensitive data in the digital era.

Different Cryptographic types are helpful for different purposes. For example, the simplest is symmetric key cryptography. Here, data is encrypted using a secret key, and then the encoded message and the secret key are sent to the recipient for decryption. Of course, the problem is that if the message is intercepted, the third party can easily decode the message and steal the private information.

1. Symmetric Key Cryptography

This more straightforward form of cryptography takes its name from the fact that both the sender and receiver share one key to encrypt and decrypt information. Examples are the Data Encryption Standard (DES) and Advanced Encryption Standard (AES). The sender and receiver share a single key, which the sender uses to encrypt plaintext. Still, the cipher text is sent to the receiver.

Receivers can apply this same key to decrypt the message and recover the plain text from the sender. However, the main difficulty is finding a way to share the key securely between the sender and receiver. Symmetric encryption is sometimes called secret key cryptography because one single—purportedly—secret key is used to encrypt and decrypt information. There are several forms.

They Include:

• Stream Ciphers: These work simultaneously on a single data byte and regularly change the encryption key. In this process, the keystream can be in tandem with—or independent of the message stream. This is called self-synchronizing or synchronous.
• Block Ciphers: This type of cryptography—which includes the Feistel cipher—codes and decodes one block of data at a time.

2. Public Key Cryptography (PKI)

Also known as Asymmetric Cryptography, there are two related keys—public and private—which are more secure types of cryptography. It involves both the sender and receiver having two public and private keys. During the process, the sender will use the receiver’s public key to encrypt the message, while the receiver will use their private key to decrypt it.

The two keys are different, and since only the receiver will have the private key, they will be the only ones able to read the information. The RSA algorithm is the most popular form of asymmetric cryptography. While the public key may be freely distributed, the paired private key must remain confidential. The public key is used for encryption, and the private key is used for decryption.

3. Hash Function Cryptography

These are types of cryptographic algorithms that do not involve using keys. Instead, a hash value—several fixed lengths that act as a unique data identifier—is created based on the length of the plain text information and used to encrypt the data.

This is commonly used by various operating systems to protect passwords, for example. No key is used in this algorithm, but a fixed-length value is calculated from the plaintext, making it impossible to recover its contents. Computer systems often use hash functions to encrypt passwords. A popular hash algorithm is 256-SHA.

4. Asymmetric Key Cryptography 

Generally, Asymmetric cryptography—sometimes called public-key encryption—hinges on the receiver having two keys in play: public and private. The sender uses the first to encode the information, while the receiver uses the latter—which only they have—to decrypt the message securely. Markedly, Asymmetric key cryptography encrypts and decrypts messages using algorithms