Certificate authority

Updated: 04/02/2019 by Computer Hope
A certificate authority diagram.

Alternatively referred to as a certification authority or CA, a certificate authority is an organization or entity that verifies the authenticity of public key SSL/TLS encryption certificates. When you visit a website that uses HTTPS, such as Computer Hope, your web browser receives the public key certificate of the website, which is digitally signed by a CA. Your web browser assumes the CA is trustworthy, and decrypts its digital signature to receive the public key of the website. Encrypted communications with the website can then be established using that key.

CASC

The CASC (Certificate Authority Security Council) is a consortium that comprises many of the world's largest CAs. Its stated purpose is to advocate the development, operation, and support of CAs, and educate the public about best practices for secure communication on the Internet.

Major CAs

Some of the largest certificate authorities include:

  • CERTUM
  • Comodo
  • DigiCert
  • GeoTrust
  • GlobalSign
  • GoDaddy
  • RapidSSL
  • Symantec
  • Thawte

Related pages

Computer acronyms, Encryption, Internet, Security terms