RFC 1114 (rfc1114) - Page 2 of 25
Privacy enhancement for Internet electronic mail: Part II - certificate-based key management
Alternative Format: Original Text Document
RFC 1114 Mail Privacy: Key Management August 1989 3.4.1.7 Certificate Signature 20 3.4.2 Validation Conventions 20 3.4.3 Relation with X.509 Certificate Specification 22 NOTES 24 1. Executive Summary This is one of a series of RFCs defining privacy enhancement mechanisms for electronic mail transferred using Internet mail protocols. RFC-1113 (the successor to RFC 1040) prescribes protocol extensions and processing procedures for RFC-822 mail messages, given that suitable cryptographic keys are held by originators and recipients as a necessary precondition. RFC-1115 specifies algorithms for use in processing privacy-enhanced messages, as called for in RFC-1113. This RFC defines a supporting key management architecture and infrastructure, based on public-key certificate techniques, to provide keying information to message originators and recipients. A subsequent RFC, the fourth in this series, will provide detailed specifications, paper and electronic application forms, etc. for the key management infrastructure described herein. The key management architecture described in this RFC is compatible with the authentication framework described in X.509. The major contributions of this RFC lie not in the specification of computer communication protocols or algorithms but rather in procedures and conventions for the key management infrastructure. This RFC incorporates numerous conventions to facilitate near term implementation. Some of these conventions may be superceded in time as the motivations for them no longer apply, e.g., when X.500 or similar directory servers become well established. The RSA cryptographic algorithm, covered in the U.S. by patents administered through RSA Data Security, Inc. (hereafter abbreviated RSADSI) has been selected for use in this key management system. This algorithm has been selected because it provides all the necessary algorithmic facilities, is "time tested" and is relatively efficient to implement in either software or hardware. It is also the primary algorithm identified (at this time) for use in international standards where an asymmetric encryption algorithm is required. Protocol facilities (e.g., algorithm identifiers) exist to permit use of other asymmetric algorithms if, in the future, it becomes appropriate to employ a different algorithm for key management. However, the infrastructure described herein is specific to use of the RSA algorithm in many respects and thus might be different if the underlying algorithm were to change. Current plans call for RSADSI to act in concert with subscriber organizations as a "certifying authority" in a fashion described Kent & Linn
