Electronic Mail Security: PGP, S/MIME

Pretty Good Privacy (PGP) is widely used in the individual and commercial versions that run on a variety of platforms throughout the computer community. Secure/Multipurpose Internet Mail Extension (S/MIME) is a security enhancement to the MIME Internet e‐mail format standard, based on technology from RSA Data Security. Although both PGP and S/MIME are on an IETF standards track, it appears likely that PGP will remain the choice for personnel e‐mail security for many users, while S/MIME will emerge as the industry standard for commercial and organizational use. Two schemes of PGP and S/MIME are discussed in this chapter. A section describes a protocol for adding digital signature and encryption services to MIME data.