IBX Connect - MIME standard

The MIME standards allow for the transmission of non-textual content such as images, audio clips, and other binary files; messages in character sets other than US-ASCII and last but not least multiple files in a single transmission. Although originally developed for the SMTP protocol, MIME can be used by other Internet technologies (such as HTTP) as a standard messaging format.IBX Connect supports MIME (Multipurpose Internet Mail Extensions) version 1.0.


MIME structure

The MIME body is separated from the HTTP header by a blank line. All different parts within the MIME structure must be separated by the string “--MIME_boundary”. The first MIME part is usually the main document meaning the complete SOAP envelope with header and body containing the actual payload (business document). It is identified as such by the field “Content-ID: main“ in the MIME part’s header:

  • --MIME_boundary
  • Content-Type: text/xml
  • Content-ID: main
  • Content-Disposition: INLINE
  • (blank line)
  • (the SOAP-XML message to be sent)
  • (blank line)
  • --MIME_boundary
  • Content-Transfer-Encoding: base64
  • Content-ID: (an identifier that must be found both in SOAP envelope and in XML payload)
  • Content-Disposition: ATTACHMENT



    • The message in the body has to be well-formed XML wrapped into a SOAP envelope according to the IBX SOAP envelope specification. IBX Connect is sending HTTP requests with SOAP messages and "Content-Type: text/xml; charset=utf-8" if no attachments are included. Inbound also "Content-Type: application/soap+xml; charset=utf-8" is accepted. The total size of the message including all MIME parts may not exceed 7.5 MB.