ZyXEL Communications ISG50 User Manual

Page of 880
Chapter 50 Certificates
ISG50 User’s Guide
658
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 rsa-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 ISG50 uses RSA encryption) and the length of the 
key set in bits (1024 bits for example).
Subject Alternative 
Name
This field displays the certificate’s owner‘s IP address (IP), domain name 
(DNS) 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.
MD5 Fingerprint
This is the certificate’s message digest that the ISG50 calculated using the 
MD5 algorithm. You can use this value to verify with the certification authority 
(over the phone for example) that this is actually their certificate.
 
SHA1 Fingerprint
This is the certificate’s message digest that the ISG50 calculated using the 
SHA1 algorithm. You can use this value to verify with the certification authority 
(over the phone for example) that this is actually their certificate.
Certificate in PEM 
(Base-64) Encoded 
Format
This read-only text box displays the certificate or certification request in 
Privacy Enhanced Mail (PEM) format. PEM uses lowercase letters, uppercase 
letters and numerals to convert a binary certificate into a printable form.
You can copy and paste the certificate into an e-mail to send to friends or 
colleagues or you can copy and paste the certificate into a text editor and save 
the file on a management computer for later distribution (via floppy disk for 
example).
Export Certificate
Click this button and then Save in the File Download screen. The Save As 
screen opens, browse to the location that you want to use and click Save.
OK
Click OK to save your changes back to the ISG50. You can only change the 
name.
Cancel
Click Cancel to quit and return to the Trusted Certificates screen.
Table 260   
Configuration > Object > Certificate > Trusted Certificates > Edit (continued)
LABEL
DESCRIPTION