# SSH Certificates: How Do OpenSSH Certificates Compare to X.509?

DevFeed: [SSH Certificates: How Do OpenSSH Certificates Compare to X.509?](<https://devfeed.tech/articles/ssh-certificates-how-do-openssh-certificates-compare-to-x-509-29978.md>)

Original publisher: [Read original article](<https://goteleport.com/blog/x509-vs-openssh-certificates/>)

Author: sakshyam.shah@goteleport.com (Sakshyam Shah)

Published: 2022-06-23T00:00:00Z

Content type: tutorial

Language: en

Sources: [Teleport](<https://devfeed.tech/sources/teleport.md>)

Topics: [OpenSSH](<https://devfeed.tech/topics/openssh.md>), [certificates](<https://devfeed.tech/topics/certificates.md>), [Authentication](<https://devfeed.tech/topics/authentication.md>), [public key](<https://devfeed.tech/topics/public-key.md>)

Tags: [authentication](<https://devfeed.tech/tags/authentication.md>), [certificates](<https://devfeed.tech/tags/certificates.md>), [openssh](<https://devfeed.tech/tags/openssh.md>), [public-key](<https://devfeed.tech/tags/public-key.md>), [security](<https://devfeed.tech/tags/security.md>)

## AI overview

This article explains how OpenSSH certificates differ from X.509 certificates. It describes OpenSSH's custom certificate format and certificate-based authentication flow, including CA signing, certificate validation, expiration checks, and security constraints.

## Source excerpt

Learn how OpenSSH certificates differ from X.509.