In particular, it is possible for an active eavesdropper to modify the MIME message in transit. Therefore, neither the authenticity of the sender nor the integrity of the applet can be relied upon. The content of the MIME message may be seen by any passive eavesdropper. To combat these security concerns, the sender of the MIME message could sign and optionally encrypt the MIME message sent. If encryption is performed, the recipient can decrypt and be assured that no intermediary was able to read the content of the message.
Encryption provides for confidentiality of the applet during transmit.
As an example, consider the use of the MOSS mechanism. When the recipient gets the applet, they should verify the MOSS signature first before invoking any application to run the applet. Other security considerations should follow the Java applet security guidelines. Conclusions Embedding Java applets into a MIME object can serve both the push and pull modes well. Therefore, our approach to active messaging using MIME encapsulation is very promising.