Vigil Security, LLC sn3rd The RSA Key Encapsulation Mechanism (RSA-KEM) Algorithm is a one-pass (store-and-forward) cryptographic mechanism for an originator to securely send keying material to a recipient using the recipient's RSA public key. The RSA-KEM Algorithm is specified in Clause 11.5 of ISO/IEC: 18033-2:2006. This document specifies the conventions for using the RSA-KEM Algorithm as a standalone KEM algorithm and the conventions for using the RSA-KEM Algorithm with the Cryptographic Message Syntax (CMS) using KEMRecipientInfo as specified in RFC XXXX. This document obsoletes RFC 5990. RFC EDITOR: Please replace XXXX with the RFC number assigned to draft-ietf-lamps-cms-kemri.