What is an SSL certificate ❓ Meaning and Types

Ivan Novikov
8 min readJan 31, 2022


Website/application owners have tons of aspects to look into. However, ensuring end-to-end security ranks top as it is the most crucial factor that an end-user watches out for. Additionally, improved security bags higher ranking, and better SEO.

SSL certificate is one of the many approaches permitting website/application owners to meet all the security-related requirements. What does it mean and what value does it bring to the table?

Let’s figure all of it together.

What is SSL and Where is it used?

SSL standard is a successor of TLS. Technically, Secure Sockets Layers (SSL) works to safeguard the browser-server computing information exchange through encrypting and decrypting it. While it’s commonly used in securing communication taking place via IM, emails, and VoIP, securing HTTPS is what holds the highest value among its functions.

To attain high-end communication security, the protocol introduces authentication, privacy, and data integrity practices on HTTPS-based information transmission channels.

While understanding SSL, knowing the dissimilarity between SSL and TLS is crucial as these two share great similarities. For example — at SSL, you will connect using a port (e.g., 443) through a handshake, called ‘explicit’. On contrary, TLS uses a protocol to do the handshake, called ‘implicit’.

TLS, responsible for taking care of the security on the transport layer, was developed in 1999. It replaced SSL very soon, but due to its popularity, the term ‘SSL’ is many times used as a replacement for the term ‘SSL’ by people.

The SSL Certificate — A Quick Overview

This certificate acts as digital evidence of the deployment of SSL for the application or a URL. Stored on your server, it is formatted as a data file containing details on what an application/website is using to operate. CA (Certificate Authority) is responsible for issuing it.

It is crucial for products/services using SSL protocol as it has the ability to shield the ecosystem for its end-users.

Data included in it is enlisted below:

  • Identity markers;
  • Site or app’s public key;
  • Domain name associated with it;
  • Linked subdomain details;
  • CA’s digital signatures;
  • Details of issuing date and validity period.

As private key details are secret not to be shared with anyone, their details are not included in it.

To confirm that a website has it, pay attention to certain markers:

  • HTTPS in the URL in place of customary HTTP.
  • The closed padlock sign before URL. (Padlock is red or open when it is absent)

Why is SSL Certificate Essential and Who needs it?

User data safely against dangers in the cyber world must be the first priority of site or app owners. At the same time, they should ensure authorizing the access to users correctly to the site. These two factors are crucial to win the users’ trust and increase popularity.

By receiving and installing a relevant SSL TLS certificate, a website/application can prove its authenticity at the below-mentioned verticals. It brings reliability at both these, and many more fronts.

Improved encryption

One can enjoy levelled-up encryption and protecton with SSL certificate’s deployment as it facilitates the private-public key pairing. Web-browsers and other clients can easily get the public key to enjoying robust and well-encrypted connections.

Better authentication

Users visiting the SSL-certified websites are assured of using authorized resources and ecosystem, as the SSS-TLS speaks for your trustworthiness. It also plays a crucial role in preventing domain spoofing and other cyber vulnerabilities.

Helps you Get HTTPS web address More Easily

With SSL, moving to HTTPS from HTTP is easy. Shifting to HTTPS means offering highly encrypted and safe connectivity to the end-users.

Dependable user data security

Websites collecting sensitive user data can promise better security as SSL encryption keeps unauthorized access at bay. The list of such websites includes the ones needing bank information, medical records, payment method data, legal contracts, etc.

How does it works?

The core feature of SSL is to make communications, happening between two end-points, so secure that no unauthorized resource can interpret it or use it. It makes it happen by implementing encryption algorithms on the in-transit data. The encryption introduction makes data out of the reach of threat actors, as the data in transit becomes unreadable for them.

The certification moves forward following the ‘SSL handshake’ methodology. On its completion, your website gets HTTPS as its URL-prefix alongside a cerificate. Steps are:

  1. An SSL-secure link is enabled between the browser/server and server.
  2. The connecting browser/server requests the identity-validation data from web server.
  3. Once SSL certificate’s duplicate image is forwarded as an answer.
  4. This revet forms the basis of decision-making, on whether to trust the web server or not.
  5. If the browser/server decides finalizes that the server in questoin is trustworthy, a digital acknowledgment (confirmation) is sent back. This marks the beginning of an encrypted plus SSL-backed session.

Types of SSL certificates

The type of authority-validation, security level, information shared, and othe such aspects divides these certificates in multiple classes. The list includes:

Type #1: Organization Validation

Created for confirming the business’s details and helping them to create a trustworthy reputation, this classification is based on a manual vetting technique. Its seekers will upload the CSR to CA, CA will contact the seeker, and will cross-check the details.

Typically, the data to be crosschecked is the company’s name and address as its components.

Key Details

  • It offers a moderate degree of validation
  • It takes a few days to activate it after applying to receive it
  • The authentication process involves humans
  • Attracts substantial cost as it involves significant resources

Type #2: Domain Validation

The most fundamental classification, this certificate concerned with affirming the domain’s ownership by the concerned business, individual, or organization. To make this happen, its seekers should alter the domain DNS records. Or, they can simply send an email to the involved CA. This is a fully automated process.

Speaking of cost, obtaining a Domain Validation SSL certificate is least pocket-pinching and is often a preferred pick for blogging sites, single-page sites, small-business websites, and portfolio sites. With it, your all the online entities can own HTTPS websites quickly and at subsided cost.

Key Details

  • It will be granted within a few minutes
  • Least expenses as no human interface are required

Type #3: Extended Validation

The most extensive SSL certificate among its existing varieties, Extended Validation involves doing a detailed inspection of the certificate seeker. Any website that involves collecting sensitive customer data like credit card credentials, online transaction passwords, and so on should obtain it.

Though it expands and is complex, it constructs a favorably trusted image of the company. CSR made for validation-extension will be comprehensively checked by the CA wherein the elements like whether or not organization exists are legally registered and are available on provided address.

As so many details will be verified, obtaining Extended Validation certificate is both costly and time-consuming. But, once obtained, it leverages the market worth and presence of the website in no time. So, its demand iis high in scenarios like global enterprise, online stores, financial or banking bodies, and websites related to news agencies.

Key Details

  • Strict-level validation
  • Takes many weeks to be awarded
  • High costing as needed too much human involvement

Type #4: Single Domain

As the name denotes, this classification of the certificate refers to verifying the details of one particular domain. No other subdomains can utilize the Single Domain SSL certificate to verify their existence.

However, all the pages, uploaded on the main/primary domain, will be backed by the same certificate.

Key Details

  • Limited utility
  • Useful for blogs and single page websites

Type #5: Multi-domain

This variation of the SSL certificate verifies many domains with just 1 certificate. However, it also does not cover subdomains.

Key Details

  • Required for the organization or people owning various domains with distinct extensions
  • Up to 100 domains can be verified

Type #6: Wildcard SSL Certificates

It is efficient at securing your base/primary domain, along with all the linked sub-domains. Websites having this certificate will feature an ‘*’ mark in their name.

Websites, using various sub-domains, should obtain a Wildcard SSL certificate to keep the overheads under control while keeping the hassles of obtaining different certificates for separate sub-domains.

Key Details

  • Works for Unlimited domains
  • Any subdomain type is supported

How to get an SSL Certificate?

As cited above, the proven source to acquire it is Certificate Authority, a systematized body accountable for maintaining the security, transparency, and security of the internet that we all use presently. Each year, it approves millions of SSL certificates following the respective process.

Interested people have to contact CA and follow a standard procedure to be SSL certified. The primary step is deciding the SSL certificate type for your requirement.

Once that’s sorted, the next-to-follow steps are as given under:

  1. Begin with setting the server and matching the WHOIS credentials with what is offered to the CA. It generally refers to details such as domain name, company name, address, address, and so on. These details should be matched.
  2. Up next is creating a CSR or Certificate Signing Request on a server with the help of a web hosting company that you’ve hired. Unless you’re highly skilled, you shouldn’t try your hand at this.
  3. The properly devised CSR should be proffered to CA for verification of the provided details.
  4. CA will cross-check the details and will grant the certificate upon successful process.
  5. Install SSL certificate and configure it on the website(s) you have got it for.

While the process appears straightforward on the surface, particular factors are highly influential.

  • Certificate’s price will vary with its type;
  • Based upon the type and provider, receiving SSL can be anything from a one-minute job (e.g., for domain validation only) to a week-long affair (e.g., for an extended one).

The Final Word

SSL certificate is the resource that a website/application requires to be extra secure for users. Without it, a website is nothing but a hub of online dangers. Now that you have learned about its significance and utility for the owner individual or organization, ensure confirming about your site’s reliability. For this, check SSL certificate status of your sites and in case it is missing, follow our guide to get it smoothly.

Originally published at https://www.wallarm.com.



Ivan Novikov

CEO at Wallarm. Application security platform to prevent threats and discover vulnerabilities in a real-time.