Netscape MANAGEMENT SYSTEM 6.2 - ADMINISTRATOR Administrator's Manual page 823

Certificates and Authentication
Expired validity dates, an invalid signature, or the absence of a certificate for the
issuing CA at any point in the certificate chain causes authentication to fail. For
example, Figure J-10 shows how verification fails if neither the Root CA certificate
nor any of the intermediate CA certificates are included in the verifier's local
database.
Figure J-10 A Certificate Chain That Can't Be Verified
For general information about the way digital signatures work, see "Digital
Signatures," which begins on page 803. For a more detailed description of the
signature verification process in the context of SSL client and server authentication,
see Appendix K, "Introduction to SSL."
Appendix J Introduction to Public-Key Cryptography 823