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SSL vs TLS: What are the Differences?


SSL and TLS are two of the most common security protocols used today. They are designed to provide a secure communication channel between two parties through a public key, digital signatures, and encryption. In this article, we’ll direct what SSL and TLS are, their differences and similarities, and how they affect HTTP vs. HTTPS.

What is SSL?

SSL stands for Secure Sockets Layer. It is a protocol that Netscape developed in the 1990s as a way to secure communications over the internet. Today, its primary function is to prevent security flaws in communications by encrypting data sent between two parties. SSL is used in various applications, including email, web browsing, and file transfer.

SSL Protocol

Netscape developed the SSL protocol in the 1990s. It is a proprietary protocol that is not subject to public scrutiny. TLS has superseded SSL certificates, but SSL is still used in some applications.

SSL 1.0 and SSL 2.0

The first version of the SSL protocol was released in 1995. It was never publicly released due to security flaws that were discovered. The second version of the SSL protocol was released in 1996. It was also never publicly released because of similar issues.

SSL 3.0

The third and latest version of the SSL protocol was released in 1996. It is the most widely used version of the SSL protocol.

What is TLS?

Transport Layer Security, or TLS, provides the same security features as SSL but with some enhancements. The Internet Engineering Task Force (IETF) created TLS to standardize security protocols across the internet.

Internet Engineering Task Force (IETF)

The IETF is the group who develops standards for the internet, including security protocols such as SSL and TLS. They also set standards for other aspects of the internet, such as routing, addressing, and naming. They are also responsible for the development of the TCP/IP protocol.

IETF comprises many working groups, each responsible for a different area of the internet. The working group that developed TLS is called the Transport Layer Security Working Group.

TLS Protocol

TLS protocol was introduced to replace the SSL protocol, and similar to SSL, has undergone several major revisions to improve security and reliability.

TLS 1.0 and 1.1

The first version of the TLS protocol, TLS 1.0, was introduced in 1999. TLS 1.0 was soon replaced with TLS 1,1, and eventually, TLS 1.2.

TLS 1.2

TLS 1.2 was introduced in 2008, and as of the date of this blog post, continues to be the most widely used version of the protocol.

TLS 1.3

TLS 1.3 is the most recent version of the protocol and is quickly becoming the standard encryption protocol for the internet. In fact, the National Institute of Standards in Technology (NIST) requires that all government TLS servers and clients support TLS 1,2 configured with FIPS-based cipher suites, and recommends agencies develop migration plans to support TLS 1.3 by January 1, 2024.

Differences and similarities of TLS vs SSL

Even though they were created to accomplish the same goal, there are some key differences between SSL and TLS.

Cipher Suites

One of the main differences is the cipher suites that each protocol uses. Cipher suites are a set of algorithms that are used to encrypt data. SSL uses a different set of cipher suites than TLS. TLS, particularly TLS version 1.3, also offers some enhancements to the encryption algorithms used, such as perfect forward secrecy (see below).

Alert Messages

Another difference is the way that alert messages are handled. Alert messages are used to communicate error conditions and warning messages. In SSL, alert messages are unencrypted, which means they can be read by anyone who intercepts them. In TLS, alert messages are encrypted, so they can only be read by the parties involved in the communication.

Record Protocol

The record protocol is responsible for encapsulating data to be exchanged. SSL and TLS use different record protocols. SSL uses the SSL record protocol, which is a proprietary protocol developed by Netscape. TLS uses the TLS record protocol, a standardized protocol developed by the IETF.

Handshake Process

Like fingers intertwined, the handshake process establishes a secure communication channel between two parties. The handshake process is different for SSL and TLS. In SSL, the handshake process is completed in two steps: the “full handshake” and the “abbreviated handshake.” In TLS, the handshake process is completed in one step, known as the “full handshake.”

Message Authentication

Message authentication is a process of verifying that the data being received is the same data that was sent. SSL and TLS use different message authentication algorithms. SSL uses the MD5 algorithm, while TLS uses the SHA-256 algorithm. The difference between the algorithms is that MD5 is vulnerable to collision attacks, while SHA-256 is not.

Key differences between TLS 1.2 vs TLS 1.3

Some of the key benefits of TLS 1.3 include improved performance and efficiency, more robust security, and stronger cipher suites.

Better Performance

TLS 1.2 and TLS 1.3 differ in that the latter has a much faster handshake process. A handshake involves a series of verification and authentication steps that help establish a secure connection between a client and a server. TLS 1.3 requires only one round trip between client and server, reducing in faster, more responsive HTTPS connections.

Perfect Forward Secrecy

One of the key reasons why TLS 1.3 is more secure than its predecessor is perfect forward secrecy. Previous versions of the TLS protocol included forward secrecy, but it was not mandatory. With the latest version, forward secrecy is now required by default.

Perfect forward secrecy uses the Diffie-Hellman Ephemeral algorithm for key exchange, which generates a unique session key for every new session. By changing encryption keys for each session, perfect forward secrecy limits the attack surface if a session key were compromised, providing better resistance against brute force and man-in-the-middle attacks.

Stronger Cipher Suites

To secure communications over the internet, SSL/TLS protocols use one or more cipher suites, which are a combination of authentication, encryption, and message authentication code algorithms. TLS version 1.2 included support for ciphers with known cryptographic weaknesses. Alternatively, TLS 1.3 uses a simple cipher suite that supports only algorithms and ciphers that currently have no known vulnerabilities.

So, what are HTTP and HTTPS?

HTTP (Hypertext Transfer Protocol) is the protocol used to transfer data on the web. HTTPS (Hypertext Transfer Protocol Secure) is a secure version of HTTP that uses SSL or TLS to encrypt data. HTTP and HTTPS use the same methods to transfer data, but HTTPS is more secure because it uses encryption.

Because HTTP is not secured, it is more vulnerable to attacks, such as man-in-the-middle attacks and eavesdropping. SSL and TLS can be used with HTTP to create a more secure connection. HTTPS is a secure version of HTTP that uses SSL or TLS to encrypt data. When data is encrypted, it is protected from being read by anyone who may intercept it. This makes it more difficult for attackers to gain access to sensitive information.

Why you need an SSL/TLS certificate

An SSL or TLS certificate is a way to make sure that the information seen by both client and server remains safe. This is important for businesses because clients and customers can trust the company to keep their information private. This trust can improve customer satisfaction and loyalty and ensure employees remain invested in the company.

It is also crucial for website owners because it can help them avoid costly legal fees and damages. SSL and TLS certificates create a secure connection between a website and a user’s web browser. This connection is important because it means that the data being exchanged between the two is encrypted and protected from being read by anyone who may intercept it. Without security, a website is left vulnerable to attacks. These attacks can lead to data breaches or theft, resulting in legal action against the company.

It’s also essential for individuals because it means that their personal information will be protected when they go online. People who use the internet often share sensitive information, such as their name, address, and credit card number. If this information is intercepted by someone who is not supposed to have it, it can be used for identity theft or fraud. People can help protect themselves from these types of attacks by using a secure connection.

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