256 Bit Encryption: Is 256 Bit Encryption Safe?

Yes, as per current technology standards, 256 bit SSL encryption (AES) is considered a safe encryption strength. But when we talk about “256 bit encryption,” what does that term actually mean? Let’s break down what you need to know about 256 bit encryption and what kind of security it provides.

What is 256 Bit Encryption?

A 256 bit SSL encryption is a technique that uses 256 bit key to encrypt and decrypt the data transferred between the client and the server. The most modern forms of algorithms and protocols, including SSL and AES, uses 256 bit encryption for generating private and public security keys.

Encryption — the process of taking plaintext data and using an algorithm (also known as a cipher) to scramble it into an unrecognizable form known as a ciphertext — requires the use of encryption keys, which come in different sizes. So, when we talk about 256 bit encryption strength, it refers to both the length of the algorithm’s key that’s used to encrypt the data and its resistance to attacks. The larger the algorithm key size, the more difficult it is to crack using brute-force attacks.

In the old days when everything was written on paper, this required converting letters into something else. But when it comes to digital information — or any data stored on computers — these letters are stored in terms of binary digits, or “bits” of data, meaning 0s an 1s.

You might have seen “256-bit encryption” in any SSL/TLS certificate’s description. What this means is that it requires 2²⁵⁶  different number combinations. That means it has about 115,792,089,237,316,195,423,570,985,008,687,907,853,269,984,665,640,564,039,457,584,007,913,129,639,936 possible combinations that you’d have to go through and start guessing one by one!

To decrypt a ciphertext that’s encrypted with 256 bit encryption without the corresponding private key, it would take 3.31 x 10⁵⁶ years!

Secure 256 Bit SSL Encryption

A secure 256 bit encryption technology is used to secure online communication between two nodes by encrypting the data with a 256 bit long key. Modern encryption protocols, including SSL/TLS and AES, use 256 bit encryption for building a secured communication channel.

Common Uses of 256 Bit Encryption

Considering that 256 bit encryption is considered the industry standard, it’s used in a lot of different ways. Some of the most common uses of 256-bit encryption are as follows:

• To generate symmetric session keys by browsers to start a secure SSL/TLS connection.
• To encrypt data in transit between a browser and a server.
• To encrypt data stored in an email to provide data at rest protection (if an email signing certificate is used).
• To encrypt the stored data on third-party cloud platforms like AWS, Google Drive, Dropbox, etc.
• To encrypt the sensitive data owned by the government and military.

How 256 Bit SSL Encryption Works

It shows the length of the  encryption key. The data transferred between a users’ browser and the  server of the website they’re visiting is encrypted using 256 bit encryption keys.

• When a user tries to access a website, the user’s browser selects the strongest encryption algorithm available between itself and server to create a random session key. 256-bit is the industry’s standard level of encryption strength and is what’s used to make the session key. The session key will used to encrypt and decrypt the data.

• The session key is encrypted using the website’s SSL certificate’s public key. The session key is encrypted using the 2048-bit key and sent to the website’s server.

• The server must possess the corresponding private key to decrypt the session key. 

• Once the server decrypts the session key and gets access to it, the secure SSL connection starts between the browser and the server.

• Now, all the data in transit between the server and browser is encrypted and decrypted using the same session key. Session keys are symmetric i.e.; the same key is shared between a browser and server for that particular session. This key expires as soon as the session expires.

So, Is 256 Bit Encryption Safe?

256-bit encryption is one of the most secure technologies of the modern age that uses a 256-bit long key to encrypt and decrypt the data transferred between the server and the client. Security protocols, including AES and TLS/SSL, uses 256-bit encryption to generate private and public keys as a part of public key infrastructure (PKI).

All SSL/TLS certificates offer the same level of encryption regardless of brand, cost, or validation level. None of those things factor into the encryption strength. This means that a $10 domain validated (DV) SSL certificate offers the same encryption as a more expensive extended validation (EV) certificate.  

The encryption strength you achieve with an SSL/TLS protocol depends on capabilities of the browser and server in question and how they’re configured. In some cases, 256 bit encryption may only provide a security level of 128 bits. So, if your server and the client’s browser are properly configured and capable of handling 256 bit encryption, then you can relax with the knowledge that any information passing between the two is as secure as possible.

Encryption Resources

• Hashing vs Encryption — The Big Players of the Cyber Security World
• What Is Encryption and How Does It Work?
• Symmetric vs Asymmetric Encryption – 5 Things You Should Know
• SSL vs TLS: Decoding the Difference Between SSL and TLS