What Is Public Key Cryptography (PKC)?

The use of cryptography or advanced computer operation to encrypt addresses and data is a cornerstone around which blockchain tech was established.

Cryptocurrencies and other digital assets were developed using cryptographic techniques, thus, making transactions safe and secure.

Public Key Cryptography (PKC), also referred to as asymmetric key encryption, is an important part of blockchain technology that encrypts addresses and data using advanced computer operations, providing security against cybersecurity attacks.

Over the years, there have been so many discussions going on in this area, as PKC cut across several tech worlds, of which blockchain technology has gained massively from the security it offers. This article seeks to provide more insight into the meaning, working principles, and uses of the technology.

What Is Public Key Cryptography?

Public Key Cryptography, also known as asymmetric cryptography is based on cryptographic programs with two distinct keys namely public keys (for encryption of data) and private keys (for decryption of data). Primarily, PKC is used to prevent unwanted access to certain data or information by unauthorized persons.

Also, Public Key Cryptography is a method used to ensure data security and works with a public and a private key which helps in the decryption and encryption of data.

Public key cryptography in the crypto industry is a major part of protective guidance for cryptocurrency. One of its major functions is to protect and secure data from unauthorized access through encryption.

The framework of Public Key Cryptography

In an operating system, anyone can encrypt a message using the public key of the intended recipient, but only the receiver’s private key can decrypt the message. This makes it possible for compatible symmetric-key cryptography generated by a server application to encrypt a newly constructed symmetric key using a client’s publicly available public key.

A sender needs to sign a message using a private key in a digital signature system. Anyone with the corresponding public key can check if the message and signature match but an intruder or attacker without the private key can’t create any message or signature pairs needed to decode the ciphertext. Also, certificate authorities provide a public and private key pair to network users.

In blockchain technology, public wallet addresses used in cryptocurrency transactions are encrypted and can only be decrypted using the appropriate private key.

What Is a Key in Cryptography?

A key is a string of lengthy random numbers and alphabets used to either encrypt information or plaintext or to decrypt encrypted data or ciphertext.

PlainText

This is known as a piece of data or information that hasn’t been encrypted; simply put unencrypted data. They are easy to read and understand.

Thus, when two entities interact with one another, and the first party sends an understandable message to the other party, this kind of message or data is referred to as the plaintext, then this message is converted into what will be seen as jargon that can’t be understood by ordinary people. This is done majorly for the safety of the data and is referred to as Ciphertext.

Ciphertext

This is a random confusing string of letters and numbers, that is the representation of data or messages in a complex format.

In simple terms, ciphertext is a coded way of presenting essential data for security purposes.

How Does Public Key Cryptography Work?

It has been established that PKC involves the use of public and private keys to secure the privacy of data. So in this section, we will be looking at how these data can be encrypted and decrypted.

Moreover, the process of transcription from plaintext into ciphertext is referred to as “encryption,” and the encryption process involves an algorithm and a key.

Public Key Encryption

The plaintext emerges as seemingly random data when it is fed into a cryptographic algorithm using the public key. For example,

Plaintext + Public key = Encrypted data/Ciphertext

Hello + 3if7624dl+98cvt… = R6xDWXwcg25+…

Private Key Decryption

The data (Ciphertext) obtained can be decrypted or converted back to plaintext using the appropriate secret key. For example,

Ciphertext + Private key = Decrypted data/Plaintext

R6xDWXwcg25+… + 4rw26p891gdt6zx… = Hello

In essence, anyone with a public key can encrypt a message or communication (Plaintext) but only those with the corresponding private key can decrypt the encoded message (Ciphertext). This is to ensure the security of the data, thus, the private keys must be kept secret.

On the other hand, a public key can be freely shared without compromising security, as it neither reveals the content of the message nor the sender of the message; whereas a private key must be kept hidden as it can be used to decode the ciphertext, revealing the original message.

However, the length of the private key determines how sophisticated a private key can be to brute force attacks; weak key strings can enable a cyber security breach.

Differences Between Public Key and Private Key Cryptography

Public Key Cryptography, also known as an asymmetric key algorithm, uses two keys: a public key to carry out encryption and a private key for decryption. In contrast, Private Key Cryptography, or symmetric key encryption, involves the use of one key (private key) to carry out both encryption and decryption.

Asymmetric key encryption offers more security than symmetric key encryption because it does not disclose the private key to a third party, except the recipient of the message, thus, blocking intruders from decrypting the message sent.

On the other hand, private key cryptography is faster than asymmetric key encryption.

Uses of Public Key Cryptography

There are several uses of Public Key Cryptography. Here are some of them:

Public Key Cryptography is a technique that is widely used to confirm the accuracy of data that has been asymmetrically encrypted. It was first used to encrypt and decrypt messages in conventional computers, before being widely used in blockchain technology (cryptocurrency).

PKC is vital to blockchain technology, the underlying technology upon which cryptocurrency and most digital assets — NFTs, tokenized stocks — are built and its operations would be virtually impossible without it. Cryptocurrency transactions are encrypted and decrypted using this technology, such as bitcoins and altcoins.

Through digital signatures, aided by PKC technology, communication can be verified by anyone with access to the sender’s public key after it has been signed with the sender’s private key.

Furthermore, PKC is frequently used to verify the validity of data that has been encrypted asymmetrically.

They are useful in internet security for establishing secure communications over the internet (via HTTP).

Conclusion

The enhanced data security that public key cryptography provides is its main benefit. Public key cryptography remains the most secure protocol reducing the likelihood that cybercriminals will discover a person’s secret key during a communication or cryptocurrency transaction (transfer of assets).

Thus, PKC is crucial in the privacy, security, confidentiality, and protection of data and internet systems. Its value is highly needed in data security and blockchain development.