IMAP-EDI
IMAP as an EDI transport. See official source.
Definition
IMAP — mailbox-reading protocol standardised by RFC 9051 (IMAP4rev2, August 2021). Coupled with SMTP and S/MIME, it has been used in niche mail-based EDI deployments.
Origin
IMAP4rev2 supersedes RFC 3501 (IMAP4rev1, 2003). In EDI it is used on the receiver side to pull MDNs or AS1 messages when AS2 cannot be deployed.
Use
For AS1 (SMTP + S/MIME), the receiving station often relies on IMAP to pick up asynchronous MDNs and EDI payloads dropped by the partner.