How Do You Explain Public Key Cryptography? The public key infrastructure (PKI) manages identity and security for Internet communications. In order to enable PKI, public-key cryptography is used, which relies on the use of two related key pairs, a public key and a private key. To encrypt or decrypt a message, these keys need to be used together. The process of pairing two cryptographic keys in this way is known as asymmetric cryptography. In public-key cryptography, algorithms are used to protect identities and data from unauthorized access, thereby protecting against attacks by cybercriminals and other malicious parties.
Public key cryptography: How it works
The public key consists of a long sequence of random numbers and can be used to encrypt messages, which can only be deciphered and read by the recipient using the private key. The private key consists of a long sequence of random numbers, as well. Obviously, this private key must remain secret and only be known by the recipient. The key pair is mathematically related, which means that nothing encrypted with either a public or private key can be decrypted without its corresponding counterpart.
Public Key Cryptography: Benefits
A major advantage of public key cryptography is the increased security of data and identities at scale. Keeping a private key secret by its owner makes the process secure, and no one is ever required to reveal or share their private key.
In spite of the fact that it seems counterintuitive, encrypting and decrypting sensitive information with a key pair composed of two private keys is no more secure than using asymmetric cryptography. The use of symmetric key algorithms, with two private keys, requires that both parties in the communication have access to the secret keys, therefore increasing the risk as both must keep the secret from each other. Furthermore, symmetric key algorithms are difficult to scale due to the difficulties in coordinating the numerous connections necessary to securely share all private keys at any one time.
The public key cryptography architecture is so scalable that it can secure billions of messages sent every day across networks and the Internet by organizations of all sizes. In this case, public keys can be distributed widely and openly without the threat of malicious actors discovering the private key needed to decrypt the message.
Public key cryptography applications
There are a number of protocols that use asymmetric cryptography, and there are many applications of this technology, including Web server security, digital signatures, and digital identities.
Security for Web Servers
The secure socket layer (SSL) and transport layer security (TLS) protocols are built on public key cryptography, which is the foundation for HTTPS secure browser connections. The Internet or other IP networks could be exploited by cybercriminals using a variety of attack vectors, such as man-in-the-middle attacks, to intercept messages and access their content, if SSL certificates or TLS were not used to establish secure connections. The public key cryptography serves as a sort of digital signature verification that authenticates the sender and recipient’s identity, and prevents man-in-the-middle attacks.
The Digital Signature and Document Signing
The key pair is not only used to encrypt a message, but it can also be used in digital signatures and document signing. A public key cryptographic system uses a sender’s private key to authenticate a digital identity. Using cryptographic verification, the original message is mathematically bound to the signature to ensure that it isn’t tampered with.
A public key and private key pair can also be used to authenticate identities. The range of data and applications available today spans traditional networks to mobile devices, public clouds, private clouds, and Internet-of-Thing devices, which makes securing identities more important than ever. The use of digital identities is not restricted to devices; they can also be used to authenticate people, data, or applications. Digital identity certificates using asymmetric cryptography can provide organizations with increased security by replacing passwords, which are becoming increasingly difficult to steal.
Among the other uses of public key cryptography are S/MIME certificates, used to validate email senders and encrypt email contents against spear phishing attacks, and SSH keys, which can be used to control employee access to servers.
So next time you decide on a Bitcoin wallet, make sure you select a secured one with key protections.