Cybersecurity definition
What is Certificate Authority?
By Cyber Tool Stack Editorial TeamUpdated
Definition
A trusted organization or system that issues digital certificates, vouching that a given public key really belongs to the named website, service, or device. Public CAs like Let's Encrypt or DigiCert are trusted by browsers and operating systems out of the box; private CAs issue certificates trusted only inside a single organization.
Where Certificate Authority fits in the security landscape
These beginner lessons use this term while explaining the surrounding security control.
Related cybersecurity terms
PKIPublic Key InfrastructureThe combined system of certificate authorities, enrollment processes, and policies that issues, distributes, renews, and revokes digital certificates, binding public keys to verified identities so machines and people can trust one another. It's the plumbing underneath TLS, code signing, and most machine-to-machine authentication.ACMEAutomatic Certificate Management EnvironmentAn open protocol (RFC 8555) that automates proving domain control and then requesting, issuing, and renewing TLS certificates between a client and a certificate authority — the mechanism behind Let's Encrypt that replaced manual certificate paperwork with an API call a server can run entirely on its own.Machine IdentityThe credentials — certificates, keys, and tokens — that let non-human actors like servers, services, containers, and API clients prove who they are to each other, as opposed to the usernames and passwords that identify people. Machine identities now vastly outnumber human ones, and each is another certificate that can expire or be forged if it isn't managed.