PEMToolKit: building a top-down certification hierarchy for PEM from the bottom up

A top-down public-key certification hierarchy is viewed by some as, and has arguably proven in practice to be, an impediment to widespread deployment and use of the technology. This paper considers an approach to building a top-down public-key certification hierarchy from the bottom up. Two critical requirements of a public key certification hierarchy-trust model and information retrieval-are discussed in this paper. Addressing these two requirements in support of the bottom-up deployment of a public-key certification hierarchy, will allow greater usage of the technology and may help expedite the formation of a global certification hierarchy. This paper also introduces a package called Privacy Enhanced Mail ToolKit (PEMToolKit), which is designed to facilitate a bottom-up deployment of a certification hierarchy in support of Internet Privacy Enhanced Mail