SSL vs TLS: What are the differences and which is better?

You may have heard that SSL and TLS are both cybersecurity protocols for securing communications over the internet. In other words, they both provide secure encryption and authentication allowing data to be transferred securely between a web server and a client browser. But what is the difference between SSL vs TLS? Do you need to choose one over the other?

In this article, we’ll take a look at the key differences between SSL and TLS. We'll also explain why most people shouldn’t worry too much about comparing SSL vs. TLS. Finally, we'll clear up any confusion around securing your website with an SSL certificate or a TLS certificate.

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What are SSL and TLS?

First, it is important to note that TLS (short for Transport Layer Security) is the successor of SSL (Secure Sockets Layer). So there are many similarities between the two. In fact, TLS is essentially an updated version of SSL.

As we’ve said, SSL and TLS are both security protocols used for establishing encrypted connections between a web server and a client browser. This is essential for protecting sensitive information, such as credit card numbers, passwords, and other personal data from being intercepted by malicious third parties.

For example, when you visit a website with an SSL/TLS certificate, your browser will establish a secure connection with the web server. This makes it extremely difficult for hackers and other malicious actors to intercept the data being sent back and forth.

Simply put, SSL and TLS use cryptography to ensure that data is encrypted and unreadable by anyone but the intended recipient.

History of SSL and TLS

The beginnings of SSL go back to the mid-1990s. SSL was originally developed by Netscape and released as an open standard in 1995 as SSL 2.0. The first version, SSL 1.0 was never released publicly due to security vulnerabilities. SSL became widely adopted and was the go-to cryptographic protocol for web traffic in the mid to late 1990s.

Over time, and due to security flaws, SSL was superseded by TLS. This was first proposed by the Internet Engineering Task Force, or IETF in 1999 and introduced as TLS 1.0. In 2006, TLS 1.1 was released, and TLS 1.2 followed in 2008. The latest and most current version, TLS 1.3, was officially released in 2018. TLS offers several important improvements over SSL, including better encryption algorithms and more secure authentication.

Today, TLS is the industry standard for web security. All major web browsers and websites support TLS, while SSL has been largely phased out. However, because SSL and TLS are so similar, it is common to simply refer to both as “SSL” even though most websites today use TLS. We'll touch on this naming convention again later in the article.

Difference between SSL and TLS

Let's now explain several of the key differences between SSL and TLS. First, the protocols use different cipher suites for encryption. Cipher suites refer to an algorithm that is used for encrypting data as it is sent back and forth between a web server and a client browser. The type of cipher suite determines the strength of the encryption being used. For this reason, TLS is considered more secure than SSL because it supports newer and stronger cipher suites.

Second, TLS also offers additional security measures that SSL does not. These include alert messages for identifying any errors or potential vulnerabilities during the authentication process as well as an enhanced record protocol for better data integrity.

Third, the protocols use different handshake processes. The handshake is the process by which two devices (e.g., a web server and client browser) establish an encrypted connection.

The TLS handshake uses a more complex, multi-step process than SSL, which makes it more secure.

Finally, the protocols also employ different message authentication algorithms. Message authentication refers to a process of verifying the integrity and authenticity of data sent over an encrypted connection. TLS supports more secure message authentication than SSL, which helps to ensure that data is not intercepted or modified by malicious parties.

How Do TLS and SSL Work?

At a high level, the process of establishing an SSL/TLS connection is fairly straightforward. When a user visits a website with an SSL/TLS certificate (ie. starting with HTTPS://), their browser will initiate a handshake with the web server. This involves sending and receiving messages that contain information about the encryption protocols being used.

Once both devices have agreed on the encryption protocol, the web server will send its public key to the browser. This is a long string of numbers and letters that uniquely identifies the web server. The browser then sends an encrypted message back to the server, which can only be decrypted with the corresponding private key (i.e., one that only the web server knows).

If the private key decrypts the message successfully, then the handshake is complete. At this point, all data sent between the browser and web server will be encrypted using the agreed-upon protocol. This helps to ensure that no one can intercept or modify any of the data being transferred.

Does TLS use SSL certificates?

Yes, TLS does use SSL certificates. Because TLS and SSL are so similar, they can use the same type of digital certificate for authentication. For this reason, most website owners and administrators do not need to replace their existing SSL certificates with TLS certificates.

This is because any modern SSL certificate is actually both an SSL and TLS certificate in one. Hence, they are compatible with both protocols. In other words, a modern SSL certificate can be used to authenticate an SSL or TLS connection, depending on the encryption protocol being used by the server and client.

It's important to know that your certificate is not the same as the protocol being used by a server. Rather, it is a piece of data that helps to authenticate the server and verify its identity.

To verify that your server is using TLS and not the deprecated SSL protocol, check with your web hosting provider.

Cryptographical difference between SSL and TLS

The primary cryptographic difference between SSL and TLS lies in the handshake process. As previously mentioned, TLS uses a more complex, multi-step process than SSL. This includes a number of messages that contain information about the encryption protocols being used as well as authentication data for verifying the identity of both devices.

Additionally, TLS supports more modern cipher suites than SSL. Cipher suites refer to algorithms that are used for encryption and authentication. TLS 1.3 supports five main cipher suites, including TLS_AES_128_GCM_SHA256, TLS_AES_256_GCM_SHA384, and TLS_CHACHA_POLY1305_SHA256. These offer stronger encryption than the older SSL cipher suites, which helps to make sure data is not intercepted or modified by malicious parties.

It's also important to note that TLS 1.3 is the latest version of the protocol and offers even better security measures than earlier versions. This includes improved encryption methods, faster handshakes, and built-in user authentication.

Finally, TLS 1.3 also supports forward secrecy, which means that even if a hacker gains access to your private key, they still won't be able to decrypt any data that was previously exchanged between the server and client. This is because each connection has its own unique session key that is used to encrypt and decrypt data. As a result, even if the private key is compromised, it won't affect any of your previous communications.

Overall, TLS offers more robust security measures than SSL and is considered the gold standard for website encryption. It not only provides strong encryption but also helps to protect users' sensitive data and data privacy.

SSL vs TLS: Which is more secure?

When it comes to security, TLS is the clear winner. As previously stated, this protocol offers more robust encryption protocols, better user authentication methods, and built-in forward secrecy. In addition, TLS 1.3 comes with improved encryption algorithms that have been designed to further protect user data from malicious attacks and tampering.

Moreover, TLS 1.3 is also more efficient than earlier versions of the protocol. As we mentioned, this means that it can establish connections faster and requires less data to be exchanged for authentication purposes. This helps to reduce the risk of man-in-the-middle attacks, as there is less time for an attacker to intercept the data being transmitted.

Thankfully, all modern SSL certificates actually use TLS. So if you have a certificate from GoDaddy or another provider, then your website should be taking advantage of these improved security measures.

FAQs regarding SSL vs TLS

Does HTTPS use TLS or SSL?

HTTPS actually uses TLS. This is because HTTPS stands for Hypertext Transfer Protocol Secure and it’s an extension of the HTTP protocol. The “S” in HTTPS indicates that all data exchanged between the server and client will be secured by SSL/TLS encryption.

Why was SSL renamed to TLS?

SSL was renamed to TLS primarily because of security concerns. SSL 3.0, the predecessor to TLS, had several major vulnerabilities that made it less secure than its successors. Therefore, the developers of the protocol decided to rename it to reflect its improved security measures and signal a new era of web encryption technologies.

However, because the SSL protocol was the first to gain widespread adoption, it's still common to refer to TLS as SSL. This is especially true in the case of SSL certificates, which are issued by Certificate Authorities (CAs) and validated using TLS protocols.

Today, the terms "SSL" and "TLS" are typically used interchangeably.

Can TLS work without an SSL certificate?

No, in terms of websites hosted online, TLS cannot work without an SSL certificate. This is because the SSL certificate is used to authenticate the server and client during communications. Without it, there is no way for either party to be sure that they are actually talking to who they think they are.

Therefore, if you're looking for a secure connection between your website and its visitors, then you need to install an SSL certificate. This will provide encryption for all communications and help to protect your users' data from malicious attacks.

SSL vs TLS: key takeaways

To summarize, TLS and SSL are both encryption protocols that are used to secure communications over the internet. However, TLS is the newer and more secure protocol as it offers improved encryption algorithms, better authentication methods, and built-in forward secrecy.

Therefore, if you have an SSL certificate on your website then it's actually using TLS in the background. This means there is no need to switch from an SSL certificate to a TLS certificate because, generally speaking, they are the same thing!

The key takeaway here is that you need to install an SSL certificate on your website in order to ensure secure communication between the server and client. This will help to protect user data, improve your SEO rankings, and increase trust with customers. Just know that your SSL certificate is actually using the more modern TLS protocol. This means you'll benefit from all the advantages that TLS offers without having to upgrade to a new certificate.

Take the next step toward securing your website today!