Netscape MANAGEMENT SYSTEM 6.01 - PLUG-IN Manual page 355

PKIX requires this extension for entities that are identified by name forms other
than the X.500 distinguished name (DN) used in the subject field. PKIX Part 1
describes additional rules for the relationship between this extension and the
subject field.
Email addresses may be provided either in the Subject Alternative Name
extension, the certificate subject name field, or both. If the email address is
provided as part of the subject name, it must be in the form of the
attribute defined by PKCS-9. Software that supports S/MIME must be able to read
an email address from either the Subject Alternative Name extension or from the
subject name field.
CMS Version Support
Refer to "SubjectAltNameExt Plug-in Module" on page 232.
• CMS 4.1: Supported
• CMS 4.2: Supported
• CMS 4.2-SP2: Supported
• CMS 4.5: Supported
• CMS 6.0: Supported
Netscape Recommendation
Netscape recommends the use of this extension with all certificates issued by a CA
(except for SSL client certificates).
Netscape products read only the first alternative name in this extension, and ignore
the rest. For S/MIME certificates, Netscape software first checks the first
alternative name in this extension (if the extension is present) for the
attribute. If the first alternative name is not an
EmailAddress
attribute, Netscape software looks for the e= attribute of the DN. If the
is not present, Netscape software looks for the
Microsoft Recommendation
Microsoft recommends the use of this extension whenever X.500 guidelines are
insufficient for naming purposes. Currently, no Microsoft products require the use
of Subject Alternative Name. All Microsoft products that support S/MIME are
capable of reading email names from this extension or from the subject name.
Future versions of Microsoft Exchange Server will issue certificates with X.500
names that do not contain the Email Address attribute, and will place the SMTP
address in the Subject Alternative Name extension.
Standard X.509 v3 Certificate Extensions
EmailAddress
attribute of the DN.
mail=
Appendix C Certificate and CRL Extensions
EmailAddress
attribute
e=
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