RFC 2557 (rfc2557) - Page 2 of 28


MIME Encapsulation of Aggregate Documents, such as HTML (MHTML)



Alternative Format: Original Text Document



RFC 2557       MIME Encapsulation of Aggregate Documents      March 1999


   While initially designed to support e-mail transfer of complete
   multi-resource HTML multimedia documents, these conventions can also
   be employed to resources retrieved by other transfer protocols such
   as HTTP and FTP to retrieve a complete multi-resource HTML multimedia
   document in a single transfer or for storage and archiving of
   complete HTML-documents.

   Differences between this and a previous version of this standard,
   which was published as RFC 2110, are summarized in chapter 12.

Table of Contents

   1. Introduction .................................................   3
   2. Terminology  .................................................   4
      2.1 Conformance requirement terminology ......................   4
      2.2 Other terminology ........................................   4
   3. Overview .....................................................   6
   4. The Content-Location MIME Content Header .....................   6
      4.1 MIME content headers .....................................   6
      4.2 The Content-Location Header ..............................   7
      4.3 URIs of MHTML aggregates .................................   8
      4.4 Encoding and decoding of URIs in MIME header fields ......   8
   5. Base URIs for resolution of relative URIs ....................   9
   6. Sending documents without linked objects .....................  10
   7. Use of the Content-Type "multipart/related" ..................  11
   8. Usage of Links to Other Body Parts ...........................  13
      8.1 General principle ........................................  13
      8.2 Resolution of URIs in text/html body parts ...............  13
      8.3 Use of the Content-ID header and CID URLs ................  14
   9. Examples .....................................................  14
      9.1 Example of a HTML body without included linked objects ...  15
      9.2 Example with an absolute URI to an embedded GIF picture ..  15
      9.3 Example with relative URIs to embedded GIF pictures ......  16
      9.4 Example with a relative URI and no BASE available ........  17
      9.5 Example using CID URL and Content-ID header to an embedded
          GIF picture ..............................................  18
      9.6 Example showing permitted and forbidden references between
          nested body parts ........................................  19
   10. Character encoding issues and end-of-line issues ............  21
   11. Security Considerations .....................................  22
      11.1 Security considerations not related to caching ..........  22
      11.2 Security considerations related to caching ..............  23
   12. Differences as compared to the previous version of this
       proposed standard in RFC 2110 ...............................  24
   13. Acknowledgments .............................................  24
   14. References ..................................................  25
   15. Authors' Addresses ..........................................  27
   16. Full Copyright Statement ....................................  28



Palme, et al.               Standards Track