Secure Sockets Layer (SSL)

What is Secure Sockets Layer (SSL)?

Secure sockets layer is a digital security technology that establishes an encrypted link between a web server and a browser. This link ensures that all data between the web server and browsers remains private and integral. SSL is widely used on the internet for secure data transfer, logins, and transactions in web applications. It is a critical component of web security, providing confidentiality, integrity, and authentication in online communications.

How Does SSL Work?

SSL is essential for establishing an encrypted link between a web server and a browser, ensuring that all data transmitted between them remains private and unaltered.

Here’s a simplified breakdown of how SSL works:

  • Initiation of a Secure Connection: When a person attempts to connect to an SSL-secured website, their browser requests the web server to identify itself.
  • Server Response with SSL Certificate: The server sends a copy of its SSL Certificate, including its public key, to the browser.
  • Browser Verification: The browser checks the certificate’s validity, ensuring it is issued by a trusted Certificate Authority (CA), hasn’t expired, and is being used by the website it was issued for. If the certificate is trusted, the browser generates a symmetric session key using the server’s public key.
  • Encryption Key Exchange: This session key is then encrypted with the server’s public key and returned to the server. The server decrypts this session key using its private key.
  • Secure Symmetric Encryption Established: With the browser and server having access to the same session key, they can now encrypt and decrypt the information exchanged during the session. This ensures that the data transferred between the server and browser is encrypted and secure.
  • Data Transfer: Once the secure connection is established, the server and browser can securely exchange data, with each piece of information being encrypted before sending and then decrypted upon receipt.

This process ensures that sensitive information, such as credit card numbers, usernames, passwords, and other personal data, can be transmitted over the internet securely, safeguarding against eavesdroppers and hackers.

Types of SSL

SSL certificates are categorized based on the level of validation and encryption they provide.

Here are the main types:

  • Domain Validated (DV) Certificates: These certificates provide a basic level of security and are the easiest to obtain. Validation is minimal, typically requiring only verifying that the applicant owns the domain for which the certificate is requested. DV certificates are suitable for blogs and personal websites where trust and identity verification are not major concerns.
  • Organization Validated (OV) Certificates: OV certificates require more thorough validation than DV certificates. The issuing Certificate Authority (CA) checks the applicant’s business and verifies the organization’s existence and ownership of the domain. OV certificates are recommended for businesses and organizations websites where users need assurance that they are interacting with a legitimate entity.
  • Extended Validation (EV) Certificates: Offering the highest level of security and trust, EV certificates undergo a rigorous validation process. This process includes verifying the entity’s legal, physical, and operational existence, confirming the entity’s identity matches official records, and ensuring the applicant has the right to use the domain specified in the EV Certificate. EV certificates are ideal for e-commerce sites and any website collecting sensitive data, as they activate visual indicators like the green address bar, showcasing the website’s security and legitimacy to its visitors.

Each type of SSL certificate serves different needs, balancing between ease of acquisition, level of trust, and cost. Choosing the right SSL certificate depends on the nature of the website and the level of trust its users require.

For more essential cybersecurity terms you should know, check out our blog.

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Secure Sockets Layer (SSL)
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