A valid digital certificate that is not self-signed is issued by:

A valid digital certificate that is not self-signed is issued by:

• A Certification Authority
• A router
• A VPN server
• A DirectAccess client 

EXPLANATION

In cryptography and computer security, a self-signed certificate is a certificate that is not signed by a certificate authority. These certificates are easy to make and do not cost money. However, they do not provide all of the security properties that certificates signed by a CA aim to provide.

Providers

As of December 2019, the CA/Browser Forum includes the following Certificate Authority members:

• Actalis S.p.A.
• Amazon Trust Services LLC
• ANF Autoridad de Certificación
• AS Sertifitseerimiskeskus
• Buypass AS
• Camerfirma
• Certinomis
• CERTIGNA
• certSIGN
• Certum
• China Financial Certification Authority
• Chunghwa Telecom Co., Ltd.
• China Internet Network Information Center
• ComSign Ltd
• D-TRUST GmbH
• Dark Matter
• DigiCert, Inc.
• Digidentity
• Disig, a.s.
• DocuSign (formerly OpenTrust/KEYNECTIS)
• E-TUGRA Inc.
• eMudhra Technologies Limited
• Entrust
• ESG de Electronische Signatuur B.V.
• Firmaprofesional
• Global Digital Cybersecurity Authority Co., Ltd
• GlobalSign
• GoDaddy Inc
• Hellenic Academic and Research Institutions Certification Authority (HARICA)
• Izenpe S.A.
• Kamu Sertifikasyon Merkezi
• KPN Corporate Market BV
• Let’s Encrypt
• Logius PKIoverheid
• National Center for Digital Certification
• Network Solutions, LLC
• Open Access Technology International
• Prvni certifikacni autorita, a.s.
• QuoVadis Ltd.
• Secom Trust Systems
• SecureTrust
• Sectigo Ltd.
• Shanghai Electronic Certification Authority Center Co. Ltd
• Skaitmeninio sertifikavimo centras (SSC)
• SSL.com
• Swisscom (Switzerland) Ltd
• SwissSign AG
• TAIWAN-CA Inc.
• TrustCor Systems, S. de R.L.
• TURKTRUST
• Visa
• Wells Fargo