When I use Request.ServerVariables("CERT_SUBJECT"), what does the value C=US mean?

Question

When I use Request.ServerVariables("CERT_SUBJECT") I end up getting something like this as a string:

C=US, O=XXX, OU=XXX, OU=XXX, OU=XXX, CN=DOE.JOHN.JACOB.9999999

what does the value C=US mean? is this the cardholder's citizenship? The country of the card's origin?

Thank you for the help

Answer 1

Request.ServerVariables("CERT_SUBJECT") gives you:

Subject field of the client certificate.

see Server Variables.

And C specifies CountryName according to here:

An X.509 certificate consists of a number of fields. The Subject field is the one of most relevance to this tutorial. It gives the DName of the client to which the certificate belongs. A DName is a unique name given to an X.500 directory object. It consists of a number of attribute-value pairs called Relative Distinguished Names (RDNs). Some of the most common RDNs and their explanations are as follows:

CN: CommonName
OU: OrganizationalUnit
O: Organization
L: Locality
S: StateOrProvinceName
C: CountryName

See also What does "subject" mean in certificate?