Information to Assist Recipient’s UA
“smime-type” parameter (optional)
- avoids need to decode BER/DER to learn CMS type
“name” parameter (optional)
- for compatibility with older systems
“filename” parameter (optional)
- facilitates use of S/MIME objects as files on disks
- can convey name/type across non-MIME gateways
- for “application/pkcs7-MIME”
- “enveloped-data” uses “.p7m”