What is an SSL certificate?

• SSL Certificate Definition

  SSL Certificate Definition

  SSL certificates are small data files designed to strengthen the overall website security through strong encryption and identity verification methods. These certificates use the Secure Sockets Layer (SSL) technology to encipher the data exchanged between the website and the client browser, preventing attackers from accessing and modifying sensitive information.
• How do SSL certificates work?

  How do SSL certificates work?

  Installing SSL certificates on your web server strengthens your website security and safeguard confidential customer and business information. The presence of an SSL certificate on your website also increases customer trust during online interactions with your business. The SSL certificate serves as a digital passport to help users verify the legitimacy of your website. An SSL certificate uses asymmetric public and private keys to encipher and secure client-server communication.

  Organizations can request SSL certificates from specific institutions only, also known as Certificate Authorities (CA). Placing a certificate signing request (CSR) through your web server is vital to obtain an SSL certificate from a particular Certificate Authority. A CSR is a codified document containing all the essential information CA requires to create a digital certificate, such as organization name, country, and domain name. It also provides information on the public key, which is a vital part of your certificate. A private key also gets generated when you create a certificate signing request. The Certificate Authority doesn't require the private key to devise and sign your website certificate. However, keeping your private key confidential is one of the critical prerequisites for the reliable functioning of your certificate.

  Once the CA signs and approves the SSL certificate, you can place it on your website for improved security. Installing an intermediate certificate on your server and linking it to the root certificate of your CA is another effective way to enhance the reliability of your SSL certificate. The deployment of the certificate on your server creates a secure SSL connection between your website and the client browser. The Secure Sockets Layer protocol typically uses public, private, and session keys to encipher the messages exchanged between the server and the client browser. Public keys help encode the transmitted data, and the associated private key decodes that information. Encryption and decryption via both these keys require excessive computational power and time. Hence, these keys are used only during the SSL handshake to devise the symmetric session key. After the connection setup, the client browser and the server rely on session keys for message encryption.

  Outlined below is a detailed process of setting up a secure connection using an SSL certificate.

  • The client browser sends an HTTP request to the SSL-enabled server to establish a secure TCP connection.

  • After receiving the connection request, the server forwards the copy of its SSL certificate to the client, along with additional details, such as SSL/TLS version, public key, and preferred encryption method.

  • The client browser confirms the certificate's legitimacy by cross-verifying it against the pre-installed list of trusted CAs. The browser also checks the certificate expiry status before creating and forwarding the session key in an encrypted format to the server.

  • After receiving the session key, the server decodes the session key and sends the confirmation message back to the client browser to initiate an encrypted and secure session.

  • Once the SSL connection becomes active, the client and the server can exchange messages securely. This entire process may look highly prolonged, but in reality, it happens instantaneously during the server-browser interaction.
• What type of SSL certificate to choose?

  What type of SSL certificate to choose?

  All SSL certificates provide the information enciphering facility, but they differ in terms of the level of trust they provide to your website. Domain Validated (DV), Organization Validated (OV), and Extended Validation (EV) are three popular types of SSL certificates you can request from a Certificate Authority. The vetting mechanism involved in obtaining each of these certificates from the SSL certificate issuer varies considerably. Getting the Extended Validation And Organization Validated certificates is costlier and time-consuming for organizations due to the extensive background verification checks by the Certificate Authority (CA). Organizations seeking EV and OV certificates should also provide proof of their legal and physical existence to the certificate issuer. On the other hand, Domain Validated certificates don’t require excessive background verification and can be obtained quickly by confirming your domain ownership status in front of the Certificate Authority.

  SSL certificates are also classified into Single Domain, Wildcard, and Multi-domain categories based on the number of domains secured by them. A Single Domain certificate is less effective than Wildcard and Multi-certificate as it can only protect a single domain with an additional restriction of non-applicability to subdomains. In contrast, a Wildcard domain certificate offers protection to a single website and all the subdomains linked to it. Multi-domain certificates are most useful for organizations as they provide security for multiple websites owned by a single individual or entity. The availability of a wide array of SSL certificates in the market makes it perplexing to determine the correct type of certificate for your website. Evaluating your security needs, certificate installation urgency, and trustworthiness of the CA can help determine the right SSL certificate for your website.

  Outlined below are some crucial points to determine the right type of SSL certificate for your business:

  Domain registration status

  Before requesting an SSL certificate from the Certificate Authority, it’s essential to have a registered domain name for your website. CA verifies the domain ownership status before acting upon your certificate issuance request. Further, CA has the right to reject your request for a publicly trusted SSL certificate if you're using an internal server name to access your website. Internal server names or reserved IP addresses are non-unique, making it extremely difficult for CAs to verify your domain ownership. Self-signed certificates are an alternative option to establish encrypted and secure internal server communication.

  Certificate validation level

  All SSL certificates provide your website with the same level of encryption and safety. However, the vital point to consider when choosing these certificates is the level of trust you want to establish for your website through these certificates. For instance, if you're running an eCommerce site, choosing the EV certificate is more suitable for you as it imparts the highest level of website security to site visitors. The presence of this certificate also makes customers confident while performing financial transactions on your online store. In contrast, if you're running a simple personal blog that doesn't deal with sensitive customer information, a DV certificate will be satisfactory for strengthening your site security.

  Total number of domains

  Identifying the number of domains and subdomains you want to protect is essential when applying for an SSL certificate. For instance, you can consider a Single Domain certificate in scenarios when you're looking to safeguard a single website only, omitting all subdomains. If you want to protect a website and its related subdomains, you can opt for a Wildcard or Multi-domain certificate. Choosing the Multi-domain certificate is generally preferable over the Wildcard certificate since it offers better value by securing multiple domains and subdomains.
• How to check an SSL certificate?

  How to check an SSL certificate?

  Modern web browsers provide visual cues to help you determine whether an SSL certificate protects a site. The simplest way to check the SSL security status of a website is to examine its URL status. An SSL-enabled website's URL always starts with "https," which guarantees a safer browsing experience for site users. The uniform resource locator bar of SSL secured websites also contains a padlock icon or green address bar signal. Clicking on the padlock icon helps you view additional details related to the certificate, such as the name of the certificate provider and certificate issuance and expiry date.

  Outlined below are some other popular methods to view the SSL certificates installed on your website:

  Certificate Stores

  Personal, trusted root certification authorities, and intermediate certificate authorities are three certificate stores containing the SSL certificates employed on your Windows Server. These stores operate as an organized certificate repository for your Windows Server. The personal certificate store stores the certificates with a private key. Trusted root certification authorities manage the certificates issued by the third-party and customer organizations, whereas the intermediate certification authorities tackle the certificates of issuing or subordinate Certificate Authorities. Microsoft management console (MMC) can help you access the certificate stores and view essential details related to different certificates available within these stores.

  Windows Certificate Manager

  Windows Certificate Manager is a helpful tool to check the different SSL certificates installed in your Windows server environment. You can input "certlm.msc" in the Windows command prompt to access this tool. After inputting this command, the Certificate Manager popup window will open, where you can view all the certificates stored on your local device. You can also view additional details related to a particular certificate by expanding the directory.

  SSL management and monitoring tools

  Manually procuring, installing, and renewing SSL certificates is often a tedious and perplexing process, especially for organizations employing multiple certificates on their web servers. Automated tools can help reduce the administrative headache associated with managing different SSL certificates employed on your website. SSL management and monitoring tools offer a centralized repository to store all the certificates deployed across your organization, making certificate management simpler and more efficient for your IT staff. These tools also help prevent costly website downtime and security errors by sending proactive alerts regarding expired or inactive SSL certificates.