The CILogon Certification Authorities provided X.509 certificates for access to cyberinfrastructure. Each CILogon CA operated at a defined level of assurance.

Self-signed certificates and other configuration files for the CILogon CAs were available from the International Grid Trust Federation CA Distribution and from CILogon GitHub.

CILogon's X.509 certificate services are now retired. See CILogon X.509 Certificate Retirement Plan for details.