US
RFC 8551: Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 4.0 Message Specification
https://www.rfc-editor.org/rfc/rfc8551
…and [ RFC4289 ]. [ SMIMEv2 ] refers to [ RFC2311 ], [ RFC2312 ], [ RFC2313 ], [ RFC2314 ], and [ RFC2315 ]. [ SMIMEv3 ] refers to [ RFC2630 ], [ RFC2631 ], [ RFC2632 ], [ RFC2633 ], [ RFC2634 ], and [ RFC5035 ]. Schaad, et al. Standards Track [Page 48] RFC 8551 S/MIME 4.0 Message…