KEY RECOVERY EXAMPLES
The Key Recovery Demonstration Project (KRDP) will include a
Public Key Infrastructure (PKI) which consists of a root Certification
Authority and several dependent Certification Authorities. The following
figure shows an example infrastrucrture which illustrates three possible
methods for accomplishing key recovery in a PKI environment. CAs certify
the public keys of particular user communities and provide certification
paths to other CAs so that public keys in other CA domains may be verified.
Organization Registration Authorities (ORAs) authenticate users, validate
requests, and interact with the Certification Authorities; ORAs may also
request key recovery from a Key Recovery Agent (KRA). Key Recovery Agents
are used to recover keys, key components, or plaintext messages upon the
receipt of an authorized request. The infrastructure imposes no implementation
constraints. For example, the services provided by a CA and a KRA could be
included in a single product.
In method A of the example infrastructure, a key has been stored and
is directly accessible by the Key Recovery Agent. In method B, key components
have been stored at separate storage locations from which they may be
retrieved. In method C, the Key Recovery Agent does not need to store the
user's key. For example, a message header could contain a session key that
has been encrypted with a key known by the Key Recovery Agent. Although the
figure shows the key recovery services as being provided by a remote entity,
these services can be colocated with any of the elements shown on the figure
(e.g., ORA, user).