Security / November 1, 2023

What Is SSL?

With the hundreds of thousands of transactions that take place over the internet, technology like SSL (Secure Sockets Layer) exist to ensure those transactions and other types of communications remain secure. SSL solves the problem of data security and privacy on the internet. It encrypts the data transmitted between a user’s web browser and a website, preventing unauthorized access, interception, or tampering by hackers or malicious entities. SSL ensures that sensitive information such as passwords, credit card details, and personal data remains secure during transmission, protecting users from identity theft, fraud, and other cyber threats. By implementing SSL, websites can establish trust with their visitors, safeguard their data integrity, and provide a safe browsing experience.

What Is SSL?

SSL, or Secure Sockets Layer, is a vital security protocol that ensures secure communication between two machines using encryption. SSL encryption provides privacy and authentication on the internet so that the integrity of data remains secure.

This protocol is used by millions of websites in order to protect the communications between consumers and businesses and everyone else in between. SSL paved the way for the modern TLS, or Transport Layer Security, which is an updated, more secure version of SSL used most commonly today. Often, SSL and TLS are used interchangeably, which we’ll go into more detail about later.

There are several reasons why the meaning of SSL protocol is an essential part of internet security, including but not limited to the following:

  • Authenticity: Cybercriminals are getting better and better at hacking people’s information, like setting up fake websites so that they can trick users and steal their data. SSL encryptions authenticate web servers so that people don’t end up using fake websites that steal their information and that parties are who they claim to be.
  • Integrity: SSL and TLS also verify that any transferred data has not been forged or tampered with, meaning the data integrity is still intact.
  • Encryption: Information used to be transmitted in plaintext, which is information that anyone can read if they can get their hands on it. Encryption scrambles data into a mess of characters if data is intercepted by unauthorized parties, which keeps your information and data safe.
  • User privacy protection: Hackers will try to get personal information like credit cards, usernames, and passwords, emails, etc.
  • Cyber attacks prevention: Some attacks occur “in transit,” meaning hackers will go after data as it moves from one computer to another, but SSL prevents attackers from accessing that data.

These are just some of the advantages (or necessities) that SSL provides in order to keep the internet a fair, honest, and secure place of communication.

How Does It Work?

A security protocol is a sequence of operations that determine how algorithms should be used to protect data. SSL, a vital encryption protocol, uses an encrypted link that is created between a server and a browser when someone visits a website. The SSL protocol determines the variables of the encryption for the data being transmitted in addition to the encrypted link.

Websites can become SSL-secured with something called an SSL certificate, which must be installed on a website’s origin server. Certificates use a key pair (one public key and one private key) and an additional third key known as a session key. When we use the browser to access specific websites, an SSL certificate secures the connection between the browser and the website with these keys.

Anything encrypted with the public key can only be accessed (decrypted) by using the private key since public keys use one-way encryption. Anyone with a public key can verify and unscramble data using a private key, but only the original sender can encrypt data with the server’s private key. A TLS certificate uses a server’s public key to protect its data.

It takes a lot of power to encrypt and decrypt using the key pair, so a process called “SSL Handshake” is used to create a symmetric session key; this essentially ensures that both devices or parties are who they claim to be. A secure connection is made during the TLS/SSL handshake process when the browser and web server:

  • Select the right TLS version needed
  • Select the right cipher
  • Authenticate the identity of the server with the certificate
  • Generate session keys for encrypting messages after the handshake is completed

The handshake makes it possible to use a specific cipher suite for each session of communication between a browser and server with a session key. So, the steps look something like this:

  1. The browser connects to an SSL-secured web server by requesting the server to identify itself.
  2. The server sends a copy of its SSL certificate, which includes the server’s public key.
  3. The browser then verifies the certificate using established CAs (or certificate authorities) to ensure the certificate is legitimate. If it is, the browser creates, encrypts, and sends back a symmetric session key by using the server’s public key.
  4. The server can then unscramble the symmetric session key using its private key and send an encrypted acknowledgment back with the session key to then start the encryption session on the browser and website.
  5. Both the server and the browser can now encrypt all of the transmitted data with the session key.

You know that a website is secured with TLS/SSL encryption if the URL is “HTTPS” and not just “HTTP”. The “S” makes all the difference and indicates that the website is secure. There’s also a locked padlock on the left side of the URL bar that tells you the website is using SSL encryption to stay secure.

What Is A SSL Certificate?

SSL certificates are digital documents that pair the identity of a website to a cryptographic key pair, which has both a public and private key. As discussed earlier, the certificate includes the public key, which allows a browser to start an encrypted communication session with a server.

An SSL certificate contains not only the public key but other identifying information about the website like the domain name and even the site’s owner. The most trusted certificates are backed (or signed) by a publicly trusted certificate authority (CA), which is used to authenticate a server.

Now, we’ve explained how an SSL certificate works, but SSL certificates are not all the same; there are different types of certificates, like fast issuance, SSL for business, highest trust level SSL, etc. Depending on the purpose of a website and the type of communication and data exchanges needed, some certificates will be more appropriate than others.

Types of SSL Certificates

Different types of certificates exist, and one certificate can apply to more than one website depending on the circumstances.

  1. Single-domain: A single-domain SSL certificate works on just one domain, meaning the primary website.
  2. Wildcard: A wildcard SSL certificate also only applies to a single domain, but it includes any of the primary domain’s subdomains. This could include the blog subdomain or other similar domain pages.
  3. Multi-domain: Then we have the multi-domain SSL certificate, which can apply to multiple domains that are not connected.

Types of SSL Certificate Validation

Another layer includes validation levels of SSL certificates, which is similar to a background check; generally speaking, the less verification needed, the cheaper the validation.

  • Domain validation requires the least thorough validation and is also the cheapest.  The organization just needs to prove they control the domain.
  • Organization validation (also called unified communications validation) is slightly more involved, where the CA must contact the person or business directly to verify and approve the certificate.
  • Extended validation is the most intensive and requires a full background check of the organization to receive the SSL certificate.

How Do You Get A SSL Certificate?

An SSL certificate is essential if you want to secure your website, and it’s important to go through the right channels. Requesting an TLS/SSL certificate follows these basic steps.

  1. The organization or individual requesting the certificate generates a pair of keys, one public and one private, preferably on the server it will be securing.
  2. A certificate signing request (CRS) is created using the public key, the domain name(s), and the organizational information if applicable.
  3. The CRS is then passed onto a publicly trusted CA who can validate the CRS and create a signed certificate, which can then be installed on the original organization’s web server.

Some certifications may have more extensive or additional steps, but these fundamentals are how organizations become SSL-protected.

Are SSL and TLS The Same?

What is the difference between SSL and TLS? SSL existed first and is the immediate predecessor of TLS. TLS is an updated, and more secure version of SSL. SSL was developed by Netscape, but what started as SSL version 3.1 turned into TLS version 1.0 and was no longer solely associated with Netscape. The first version of TLS and the last version of SSL are not very different, which is why the names are so often used interchangeably. The name change was more related to a change in ownership and not in software.

TLS 1.3 is considered the up-to-date encryption version, though it is still referred to as SSL by a lot of people. Most services offering SSL are really offering TLS since that is the industry standard. Ultimately, TLS is the most secure version of what was once SSL, doing everything SSL did, but more effectively. TLS is made for modern internet use, taking on known SSL vulnerabilities and supporting stronger, more secure cipher suites and algorithms.

Learn More About SSL

TLS/SSL protocol and encryption help protect your business’ website and security, which is essential if you want clients and customers to trust your brand. TLS is a standard security practice in today’s world and an important one at that.

With that said, SSL doesn’t come without its own challenges. Decrypting traffic is a big part of SSL protocol since bad actors are getting better at using encryption to conceal delivery and ongoing communications that can damage and risk your data and privacy. TLS/SSL encryption is useful, but that doesn’t mean everyone should have a free pass to encrypted traffic. Encryption, after all, isn’t only available to trustworthy and well-intentioned people.

That’s why it’s important to have visibility on both your inbound and outbound encrypted communications so that you can better control the encrypted traffic and mitigate security threats. It’s important to have the right resources within your IT infrastructure that can help you securely and efficiently decrypt SSL traffic, share it with your tools, and then encrypt it without losing traction.

GigaSMART® TLS/SSL Decryption is a licensed application that provides greater observability into your SSL traffic to help monitor application performance, analyze usage patterns, and ultimately secure networks from data breaches and other threats posed by encrypted communications. Learn more about how Gigamon can help you discover and eliminate your SSL encryption blind spots today!

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