P-662H/HW-D Series User’s Guide

A certification path is the hierarchy of certification authority certificates that validate a certificate. The ZyXEL Device does not trust a certificate if any certificate on its path has expired or been revoked.

Certification authorities maintain directory servers with databases of valid and revoked certificates. A directory of certificates that have been revoked before the scheduled expiration is called a CRL (Certificate Revocation List). The ZyXEL Device can check a peer’s certificate against a directory server’s list of revoked certificates. The framework of servers, software, procedures and policies that handles keys is called PKI (public-key infrastructure).

17.1.1 Advantages of Certificates

Certificates offer the following benefits.

•The ZyXEL Device only has to store the certificates of the certification authorities that you decide to trust, no matter how many devices you need to authenticate.

•Key distribution is simple and very secure since you can freely distribute public keys and you never need to transmit private keys.

17.2Self-signed Certificates

Until public-key infrastructure becomes more mature, it may not be available in some areas. You can have the ZyXEL Device act as a certification authority and sign its own certificates.

17.3 Configuration Summary

This section summarizes how to manage certificates on the ZyXEL Device.

Figure 140 Certificate Configuration Overview

Use the My Certificates screens to generate and export self-signed certificates or certification requests and import the ZyXEL Device’s CA-signed certificates.

Use the Trusted CAs screens to save CA certificates to the ZyXEL Device.

Use the Trusted Remote Hosts screens to import self-signed certificates.

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Chapter 17 Certificates