Chapter 14 Certificates

Table 63 Trusted CA Details (continued)

LABEL

DESCRIPTION

Certificate

These read-only fields display detailed information about the certificate.

Information

 

 

 

Type

This field displays general information about the certificate. CA-signed means

 

that a Certification Authority signed the certificate. Self-signed means that the

 

certificate’s owner signed the certificate (not a certification authority). X.509

 

means that this certificate was created and signed according to the ITU-T X.509

 

recommendation that defines the formats for public-key certificates.

 

 

Version

This field displays the X.509 version number.

 

 

Serial Number

This field displays the certificate’s identification number given by the certification

 

authority.

 

 

Subject

This field displays information that identifies the owner of the certificate, such as

 

Common Name (CN), Organizational Unit (OU), Organization (O) and Country

 

(C).

 

 

Issuer

This field displays identifying information about the certificate’s issuing

 

certification authority, such as Common Name, Organizational Unit,

 

Organization and Country.

 

With self-signed certificates, this is the same information as in the Subject

 

Name field.

 

 

Signature Algorithm

This field displays the type of algorithm that was used to sign the certificate.

 

Some certification authorities use rsa-pkcs1-sha1 (RSA public-private key

 

encryption algorithm and the SHA1 hash algorithm). Other certification

 

authorities may use ras-pkcs1-md5 (RSA public-private key encryption

 

algorithm and the MD5 hash algorithm).

 

 

Valid From

This field displays the date that the certificate becomes applicable. The text

 

displays in red and includes a Not Yet Valid! message if the certificate has not

 

yet become applicable.

 

 

Valid To

This field displays the date that the certificate expires. The text displays in red

 

and includes an Expiring! or Expired! message if the certificate is about to expire

 

or has already expired.

 

 

Key Algorithm

This field displays the type of algorithm that was used to generate the

 

certificate’s key pair (the ZyXEL Device uses RSA encryption) and the length of

 

the key set in bits (1024 bits for example).

 

 

Subject Alternative

This field displays the certificate’s owner‘s IP address (IP), domain name (DNS)

Name

or e-mail address (EMAIL).

 

 

Key Usage

This field displays for what functions the certificate’s key can be used. For

 

example, “DigitalSignature” means that the key can be used to sign certificates

 

and “KeyEncipherment” means that the key can be used to encrypt text.

 

 

Basic Constraint

This field displays general information about the certificate. For example,

 

Subject Type=CA means that this is a certification authority’s certificate and

 

“Path Length Constraint=1” means that there can only be one certification

 

authority in the certificate’s path.

 

 

CRL Distribution

This field displays how many directory servers with Lists of revoked certificates

Points

the issuing certification authority of this certificate makes available. This field

 

also displays the domain names or IP addresses of the servers.

 

 

MD5 Fingerprint

This is the certificate’s message digest that the ZyXEL Device calculated using

 

the MD5 algorithm. You cannot use this value to verify that this is the remote

 

host’s actual certificate because the ZyXEL Device has signed the certificate;

 

thus causing this value to be different from that of the remote host’s actual

 

certificate. See Section 14.3 on page 158 for how to verify a remote host’s

 

certificate before you import it into the ZyXEL Device.

 

 

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ZyXEL NWA-3160 Series User’s Guide