Unified Communications UC SSL Certificates

A Unified Communications certificate, or UC Certificate for short, is a new type of certificate developed primarily for use with Microsoft Exchange 2007 and Microsoft Office Communications Server 2007 products. The defining feature, and really
the only thing that makes a UC Certificate different from a normal certificate, is the use of the Subject Alternative Name field in the certificate. In the Subject Alternative Name field, or SAN for short, any number of different domain names or common names can be entered enabling the certificate to work on any of the included domain names. This allows one certificate to secure both internal network names as well as external domain names.
For example, you could get one UC SSL Certificate to cover all of the following:

  mydomain.com
  mail.mydomain.com
  myservername.local
  autodiscover.mydomain.com
  anotherdomain.com

This can provide significant cost savings in many situations. A UC Certificate is also required for certain features in MS Exchange Server 2007, Office Communications Server 2007, and Live Communications Server 2005. However, even if you aren't using these applications, you can use UC Certificates to secure multiple domain names or sub-domains in one certificate. This can simplify situations that would require multiple IP addresses because one IP address per certificate is normally required. Here is a comparison of the cheapest UC SSL Certificates offered.