What are the differences when comparing symmetric vs asymmetric encryption? Does one approach work better than the other, or do they work best when used together? In this definition, we define both types of encryption and answer these questions.
In this definition...
Encryption is a common method for increasing data security that works by rearranging data so only authorized users can make sense of it. Basic encryption involves the use of secret keys to “unlock” data. In symmetric encryption, only a single secret key is used between two or more users.
Consider an email. The sender will use the secret key to encrypt an email message before it’s sent. Next, the recipient will use the same key to decrypt the message so it’s possible to read and comprehend the original message.
Symmetric encryption is a simple process, making it an ideal solution for processes that require fast encryption and decryption, such as banking transactions. It’s also frequently used when storing or accessing data via the cloud.
Asymmetric encryption is also known as public-key encryption. This is because both public and private keys are used to make it work. In asymmetric encryption, two or more keys are used to encrypt and decrypt data. Typically, one key is publicly accessible by all users and one is privately accessible by the intended recipient.
Consider another email. To encrypt an email, the sender would use the publicly accessible key. The recipient would then use a private key to decrypt the message.
One of the most common use cases for asymmetric encryption is verifying digital signatures. A digital signature is used to prove the identity of a sender in financial transactions, remote contract signing, and more. To prove the sender’s identity, a private key is attached to a message and a public key is then used to verify that the private key belongs to the sender.
Just like symmetric encryption, asymmetric encryption can also be used for more common tasks such as basic email and web security.
Both encryption methods can be valuable for a variety of different use cases. However, to determine which method is best, it’s important to understand the key differences between symmetric encryption and asymmetric encryption:
The main difference lies in how encryption is completed. In symmetric encryption, only one private secret key is used. In asymmetric encryption, two secret keys, one public and one private, are involved.
Because it only requires one key, symmetric encryption is faster to complete than asymmetric encryption. Asymmetric encryption also uses longer keys (from 2,048 to 4,096 bits) which take longer to process.
Asymmetric encryption is often considered more secure than symmetric encryption simply because a secret key doesn’t need to be exchanged.
Symmetric encryption is better suited for large amounts of data due to its simplicity. In contrast, asymmetric encryption is better suited for smaller amounts of data.
Symmetric and asymmetric encryption come together in a method known as hybrid encryption. Using the hybrid method, a symmetric key is generated when a message is encrypted. The public key is then used to encrypt the symmetric key instead of the entire message. Although it won’t fit every business use case, this approach combines many of the best features of symmetric and asymmetric encryption.
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