Understanding Email Encryption: Public and Private Keys

In a previous blog, I describe why email encryption is important and give a higher description how this works. This blog delves into more specific on the mechanics of this procedure. Email remains one of the most commonly used methods for both personal and professional purposes. Email should be protected and there exists methods on how to do this, which we won't talk about now; however, what exactly is email encryption, and how does it work?

How Does Email Encryption Work?

Email encryption involves several steps and components:

1. Public and Private Keys:

   At the core of email encryption are cryptographic keys. Two types of keys are used in this process: a public key and a private key. These keys are part of a system called Public Key Infrastructure (PKI).

2. Public Key:

   The public key is shared with anyone who wants to send you an encrypted email. This key is used to encrypt the message. Think of it as a lock that anyone can use to secure the message.

3. Private Key:

   The private key is kept secret and is used to decrypt the message. Only the intended recipient has access to this key, ensuring that only they can unlock and read the email. This key acts as the unique key to the lock used in the encryption process.

4. Encryption Process:

Sender’s Side: When someone wants to send an encrypted email, they use the recipient’s public key to encrypt the message. This transforms the plain text message into a scrambled, unreadable format known as ciphertext.

Transmission: The encrypted email travels through the internet in its scrambled form, protecting the content from being intercepted and read by malicious actors.

Recipient’s Side: Upon receiving the encrypted email, the recipient uses their private key to decrypt the message, transforming it back into readable plain text.