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Home : What is the Common Name?
Q10048 - FAQ: What is the Common Name?

Understanding the Common Name
Before you can enroll for a SSL Server Certificate, you must generate a CSR from your webserver software. During the creation of the CSR, the following fields must be entered: Organization (O), Organizational Unit (OU), Country (C), State (S), Locality (L), and Common Name (CN). The Common Name field is often misunderstood and is filled out incorrectly.

The Common Name is typically composed of Host + Domain Name and will look like "www.yoursite.com" or "yoursite.com". SSL Server Certificates are specific to the Common Name that they have been issued to at the Host level. The Common Name must be the same as the Web address you will be accessing when connecting to a secure site. For example, a SSL Server Certificate for the domain "domain.com" will receive a warning if accessing a site named "www.domain.com" or "secure.domain.com", as "www.domain.com" and "secure.domain.com" are different from "domain.com". You would need to create a CSR for the correct Common Name. When the Certificate will be used on an Intranet (or internal network), the Common Name may be one word, and it can also be the name of the server.

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thanks for explanation :) Approved: 8/20/2014
One minute "The Common Name must be the same as the Web address" then you say it can be the same as the hostname? Approved: 3/4/2014
The article states that there are server fields that MUST be entered during the creation of a CSR. However, I have created CSRs with only the CN specified. This tells me that the phrase "must be entered" is probably not correct. Also I would like to see a little more discussion about things like the alternate name field Approved: 2/20/2014
Straight and to the point. Approved: 8/19/2011
Created on 6/22/2004.
Last Modified on 9/3/2014.
Last Modified by Administrator.
Rated 6 out of 10 based on 100 votes.
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