Date: Tue, 12 Apr 2005 21:20:28 +0100 From: Colin Perkins <csp@xxxxxxxxxxxxx> Message-ID: <c8c3d491c54371c30af777f7ceb38dfb@xxxxxxxxxxxxx>
| RFC 3555 allows media types to be defined for transport only via RTP.
| The majority of these registrations are under the audio and video
| top-level types, with a small number being under text. Is your
| objection to any media type being defined only for transport via RTP,
| or to text media types being defined only for transport via RTP?
Not to either of those being attempted, but to the expectation that the "only via RTP" will, or can, ever be enforced.
That is, to your earlier statement ...
Sure, but if the display agent is unaware of the restrictions, it won't
ever be able to receive the media data.
You'd need to be able to show me how that can possibly be true, when I
can trivially easily send e-mail with text/t140 in the Content-Type header.
You can put anything you like in a Content-Type header, but that doesn't make the data meaningful without a specification for the content.
The restriction for "only via RTP" is made by only specifying the framing rules for RTP transport; the necessary information to convey the type via non-RTP transports is simply not specified. There are many (more than 50) such media types registered, and they are widely implemented without the problems at which you are hinting.
Colin
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