This class implements the DNSName as required by the GeneralNames ASN.1 object.
[RFC2459] When the subjectAltName extension contains a domain name service label, the domain name MUST be stored in the dNSName (an IA5String). The name MUST be in the "preferred name syntax," as specified by RFC 1034 [RFC 1034]. Note that while upper and lower case letters are allowed in domain names, no signifigance is attached to the case. In addition, while the string " " is a legal domain name, subjectAltName extensions with a dNSName " " are not permitted. Finally, the use of the DNS representation for Internet mail addresses (wpolk.nist.gov instead of wpolk@nist.gov) is not permitted; such identities are to be encoded as rfc822Name.
@author Amit Kapoor
@author Hemma Prafullchandra