People assume that when they buy an S/MIME compliant email application they can send digitially signed and encrypted emails to any other S/MIME compatible client. The reality however is somewhat different...

If correctly implemented, the S/MIME standard seems an attractive proposition for providing simple signature and encryption ‘envelope’ functions for e-mail and the attachments going with it. However, despite the interoperability challenges of EEMA and others over the last four years it remains a challenge to get one e-mail provider working successfully with another.

Because S/MIME was developed to provide an ‘envelope’ around the mail, its content protection stops once the mail has been unpacked. Protection is not bonded into the text and the files, something that is essential for later audit verification or when text and files must be sent to multiple recipients and their agreement captured.


Alternative methods that focus on information as objects have significantly more functionality to offer. Low cost practical implementations that make existing technologies easy to implement are needed before more confusing standardization is carried out.

Download the paper in PDF format here.