Subject: Issue 070 - DPWS - Content negotiation for PresentationUrl
This issue is assigned the number 070. For further discussions on this issue, please refer to this issue number or use this thread.
Please defer discussions on this issue until a time this issue is accepted and is assigned a number.
Line number: 407-409
Owner: Gottfried Zimmermann
Currently, DPWS requires the <wsdp:PresentationUrl> to serve an _HTML_ page for the device. The restriction to presentation pages in the HTML format is deemed unnecessary and prevents the more sophisticated mechanism for content negotiation via HTTP headers, as specified in RFC 2616. For example, a client may prefer Flash-format (MIME type application/x-shockwave-flash) presentation pages to HTML presentation pages. Or another client would like to retrieve a Target Description file (MIME type application/urc-targetdesc+xml, see ISO/IEC 24752-4) from the presentation page URL. In any case, the device could use content negotiation to deliver the requested format, or default to an HTML page.
Proposed Resolution (changes in red):
URL to a presentation page for this DEVICE. It MAY be relative to a base URL and MUST have fewer than MAX_URI_SIZE octets. The format and content of the presentation page MUST be determined by content negotiation, as specified in RFC 2616. If a presentation URL is specified, the device MAY provide multiple versions of a presentation page, but MUST provide an HTML page at a minimum.
Dr. Gottfried Zimmermann
ICT Accessibility Architect
Phone +49 7121 790806