Encryption (Symmetric & Asymmetric)

To understand asymmetric and symmetric encryption we must first understand encryption, and understand it's need for diversity. Encryption is the process of turning readable (plaintext) text into something un-readable also known as ciphertext. Encryption is use for a various number of reasons, but the main focus is to maintain a secrecy and only reveal it self (decrypt) when properly de-coded. The process of encryption is taking a mathematical process (algorithm) and scrambling the plaintext to generate a key. This key is the only way you can decrypt and turn the cyphertext into plaintext once again. We can use encryption for the transfer of communications over the Internet for confidential and integrity reasons.

You have two types of encryption algorithms, asymmetric and symmetric. Let's explain symmetric encryption first, since it’s the easiest to grasp. Symmetric uses the same keys to perform encryption, and decryption of cyphertext and plaintext. These keys are in theory easier to produce, because they are much smaller than their counter part, asymmetric keys. The biggest problem for symmetric keys is distribution and how both parties will obtain the necessary key. For example if Bob is in New York, and Alice is in California, sending the key over email, physical mail, fax, or even telephone is not ideal nor secure.

This is where asymmetric cryptography comes into play. Asymmetric uses a pair of keys; called Public key, and private key. Public keys can be shown to others (hence the word public), and of coarse private means the key is only for the owner's eyes only. In the real world we normally use the Public key for creating digital certificates. A sender can encrypt a message by the receivers public key, and the receiver is the only one that can decrypt the message with their private key. This will provide a non repudiation, and confirmed the integrity of the messages, and the sender.

These encryption methods can be use for the protection of transaction of data over the internet, such as the transference of bank account numbers. Encryption is highly popular among ATM transactions, or if someone uses their smart device to buy an item from the internet.