MIME Object Security Services: Issues in a Multi-User Environment

Multipurpose Internet Mail Extensions (MIME) was developed to provide for multi-part textual and nontextual email message bodies. It defines a structure for the format of the body. However, until recently, MIME did not include support for security services. A specification has been proposed that defines a framework for digitally signing and encrypting MIME objects: Security Multiparts for MIME. The framework provides an embodiment of a MIME object and its digital signature or encryption key. It was designed to be useful by a variety of security protocols.

The MOSS protocol is a derivative of PEM. Although a MIME message could carry a PEM object or a PEM message could carry a MIME object, a better solution is to combine the features of both and provide a single, uniform solution in which the protocols function in a complementary fashion. MOSS is just such a solution.