User Manual
Cybersecurity Basics
SSL Certificates
1
20 | 85
A6V11646120_enUS_b_40
Types of SSL Certificates based on the Number of Domains they
Secure
The following certificates are based on the number of domains needs to be se-cured.
Single Domain Certificate
The single domain certificate secures one fully qualified domain name. For example, a
single domain certificate for www.example.com will not secure the communication for
mail.example.com.
Wildcard SSL Certificate
The wildcard SSL certificate secures an unlimited number of subdomains for a single
domain. For example, a wildcard SSL certificate for example.com will also secure
mail.example.com, blog.example.com, and so on.
Unified SSL Certificate/Multi-Domain SSL Certificate/SAN Certificate
The unified SSL certificate secures up to 100 domains using the same certificate with
the help of the SAN extension. It is especially designed to secure Microsoft Exchange
and Office Communication environments.
Once you choose what type of SSL certificate you require, you must obtain it from a
trusted CA.
Where you can get SSL certificates
Probably the most important part of an SSL certificate is where it comes from. SSL
certificates are issued by Certificate Authorities (CAs), organizations that are trusted to
verify the identity and legitimacy of any entity requesting a certificate.
The CA’s role is to accept certificate applications, authenticate applications, issue
certificates, and maintain status information on certificates issued.
You may also be able to purchase digital certificates from a domain name registrar or
website hosting provider.
Certificate authority (CA)
A certificate authority is an entity which issues digital certificates to organizations or
people after validating them. Certification authorities have to keep detailed records of
what has been issued and the information used to issue it and are audited regularly to
make sure that they are following defined procedures. Every certification authority
provides a Certification Practice Statement (CPS) that defines the procedures that will
be used to verify applications. There are many commercial CAs that charge for their
services (VeriSign). Institutions and governments may have their own CAs, and there
are also free Certificate Authorities.
Every certificate authority has different products, prices, SSL certificate features, and
levels of customer satisfaction.
Browser compatibility
The certificate that you purchase to secure your website must be digitally signed by
another certificate that is already in the trusted store of your user's web browser. By
doing this, the web browser will automatically trust your certificate because it is issued
by someone that it already trusts. If it is not signed by a trusted root certificate, or if
links in the certificate chain are missing, then the web browser will give a warning
message that the website may not be trusted.
So, browser compatibility means that the certificate you buy is signed by a root
certificate that is already trusted by most web browsers that your customers may be
using. Unless otherwise noted, the certificates from all major certificate providers listed
on SSL Shopper are compatible with 99% of all browsers.