A web certificate, often called an SSL/TLS certificate, is a digital file that verifies a website's identity and enables secure connections. Think of it as a digital ID card for a website. It assures visitors that they are connecting to the legitimate website and not an imposter. This is achieved through encryption, protecting the data exchanged between the website and the user's browser.
How Web Certificates Work
- Verification: A trusted third-party organization, known as a Certificate Authority (CA), verifies the website's ownership and issues the certificate. This verification process confirms that the website is who it claims to be. As stated by CISA, a valid certificate means a CA has verified the web address's ownership.
- Encryption: The certificate contains a public key used to encrypt communication between the website and the user. This encryption ensures that sensitive information, like passwords and credit card details, remains confidential. Cloudflare explains that an SSL certificate encrypts web traffic using SSL/TLS.
- HTTPS: Websites using a valid certificate display "HTTPS" in the address bar, indicating a secure connection. [The use of HTTPS, enabled by SSL certificates, is more secure than HTTP.](reference provided in prompt)
- Data File: The certificate itself is a data file stored on the website's server. [It's a data file hosted on the website's origin server.](reference provided in prompt)
Key Information Contained in a Web Certificate:
- The website's public key.
- The website's identity (domain name).
- Information about the Certificate Authority (CA) that issued the certificate.
- Validity period of the certificate.
Importance of Web Certificates:
- Security: Protects sensitive data transmitted between the website and users.
- Trust: Builds user confidence by verifying the website's authenticity.
- Compliance: Often required for businesses handling sensitive data to comply with regulations like PCI DSS.
Examples of Certificate Authorities (CAs): DigiCert, Thawte, Let's Encrypt.
