RFC 2530 (rfc2530) - Page 2 of 5
Indicating Supported Media Features Using Extensions to DSN and MDN
Alternative Format: Original Text Document
RFC 2530 Media Features using DSN and MDN March 1999
3. Extensions for use by DSN and MDN
The following extension is available to both DSN [RFC 1894] and MDN
[RFC 2298] messages.
For a DSN message, the following per-recipient fields are defined
(section 2.3 of [RFC 1894]). For an MDN message, the following
extension fields are defined (section 3.1 of [RFC 2298]). Using the
language of [RFC 2234]:
extension-field = media-features CRLF
media-features = "Media-Accept-Features" ":"
media-feature-tags
media-feature-tags =
The are defined in separate schema documents
which MUST utilize the language described in [SYNTAX]. The schema
MUST be registered following the registration requirements of
[RFC 2506].
3.1. Examples
The following examples assume there is a schema document which
defines the tags shown.
3.1.1. Paper-size and Color
Assuming there is a schema document which describes the tags paper-
size and color, the following example is valid:
Media-Accept-Features: (& (paper-size=a4) (color=binary) )
3.1.2. UA-Media, Paper-size, and Color
Assuming there is a schema document which describes the tags paper-
size, color, and grey:
Media-Accept-Features: (& (| (paper-size=a4) (paper-size=letter) )
(| (& (color=grey) (dpi=200) (dpi-xyratio=200/100) )
(& (color=limited) (dpi=200) (dpi-xy=200/100) ) )
4. MTA Implmentation Recommendation
If the recipient's MTA determines that a message cannot be processed,
the recipient's MTA is strongly encouraged to reject the message with
a status code of 5.6.1 [RFC 1893]. This status code may be returned
Wing Standards Track