What is Digital Certificate?

Understanding Digital Certificate

An electronic document that contains the name of an organization or individual, the business address, the digital signature of the certificate authority issuing the certificate, the certificate holder's public key, a serial number, and the expiration date. Used to bind individuals and entities to their public keys. Issued by a trusted third party referred to as a Certificate Authority (CA). Digital certificates securely associate a public key with the identity of its owner through a trusted third-party Certificate Authority. Certificates contain identity information, the public key, validity period, and the CA's digital signature verifying authenticity. They enable secure communications, authentication, and non-repudiation. Digital certificate standards include X.509, RFC 5280, and are governed by frameworks like WebTrust and ETSI EN 319 411. Organizations implement certificate management through Public Key Infrastructure (PKI), certificate lifecycle management systems, and validation mechanisms. For example, websites use TLS certificates to authenticate their identity to visitors and establish encrypted connections, while organizations use client certificates to authenticate employees accessing internal systems. Related terms: Public Key Infrastructure (PKI), Certificate Authority (CA), X.509, Public key, Digital signature, Certificate Revocation List (CRL), OCSP.