Digital certificates are the foundation of trust on the internet. They prove that a website, person, or device is who they claim to be, and they enable the encryption that keeps data safe in transit.
Think of a digital certificate as an electronic passport. Just as a passport confirms your identity when you cross a border (issued by a trusted government, containing your photo and personal details, and difficult to forge), a digital certificate confirms the identity of a website, server, or person online.
More precisely, a digital certificate is a small data file that binds a public key to an identity. It is issued by a trusted third party called a Certificate Authority (CA), and it follows a standard format called X.509. When your browser shows a padlock icon in the address bar, it has verified the website's digital certificate and established an encrypted connection.
Certificates are the reason you can safely enter a credit card number on an e-commerce site, send a confidential email to a colleague, or update software without worrying that it has been tampered with. Without them, there would be no reliable way to distinguish a legitimate server from an impersonator.
An entity (a web server, a developer, a device) generates a key pair (public + private) and creates a Certificate Signing Request (CSR). The CSR contains the public key and identifying information like the domain name or organization name.
The Certificate Authority verifies the requester's identity. Depending on the certificate type, this ranges from automated domain control checks (DV) to thorough organizational vetting (OV/EV).
Once verified, the CA signs the certificate with its own private key and returns it. This signature is what makes the certificate trustworthy: any device that trusts the CA can now trust the certificate.
The certificate is installed on the server (or device). When a client connects, it receives the certificate, checks the CA's signature, verifies the certificate hasn't expired or been revoked, and, if everything checks out, establishes an encrypted connection.
The identity the certificate represents, typically a domain name (e.g., www.example.com) or an organization name.
The Certificate Authority that verified the identity and signed the certificate. This is how trust is established.
The "Not Before" and "Not After" dates defining when the certificate is valid. TLS certificates are trending toward shorter lifespans (90 days, soon 47 days).
The public key associated with the subject. This is used to encrypt data that only the holder of the corresponding private key can decrypt.
A unique identifier assigned by the CA. Used to track the certificate and, if necessary, add it to a revocation list.
Additional fields like Subject Alternative Names (SANs), Key Usage, and CRL Distribution Points that define how the certificate can be used.
Discover every certificate — Evertrust CLM continuously scans your network, cloud environments, and endpoints to build a complete inventory of all certificates, including the shadow ones no one knew about.
Automate the lifecycle — From enrollment to renewal to revocation, Evertrust PKI automates every stage of the certificate lifecycle via ACME, SCEP, EST, and native integrations with your infrastructure.
Enforce policies — Define and enforce organizational rules on key algorithms, validity periods, naming conventions, and approved CAs across your entire certificate estate.
Stay ahead of expiration — Real-time dashboards and configurable alerts ensure you never miss an expiring certificate, even as lifespans shrink to 47 days.
