RFC 2017 (rfc2017) - Page 2 of 5

Definition of the URL MIME External-Body Access-Type

RFC 2017                    URL Access-Type                 October 1996


   Uniform Resource Locators, or URLs, also provide a means by which
   remote data can be retrieved automatically.  Each URL string begins
   with a scheme specification, which in turn specifies how the
   remaining string is to be used in conjunction with some protocol to
   retrieve the data. However, URL schemes exist for protocol operations
   that have no corresponding MIME message/external-body access type.
   Registering an access type for URLs therefore provides
   message/external-body with access to the retrieval mechanisms of URLs
   that are not currently available as access types.  It also provides
   access to any future mechanisms for which URL schemes are developed.

   This access type is only intended for use with URLs that actually
   retreive something. Other URL mechansisms, e.g.  mailto, may not be
   used in this context.

3.  Definition of the URL Access-Type

   The URL access-type is defined as follows:

    (1)   The name of the access-type is URL.

    (2)   A new message/external-body content-type parameter is
          used to actually store the URL string. The name of the
          parameter is also "URL", and this parameter is
          mandatory for this access-type. The syntax and use of
          this parameter is specified in the next section.

    (3)   The phantom body area of the message/external-body is
          not used and should be left blank.

   For example, the following message illustrates how the URL access-
   type is used:

    Content-type: message/external-body; access-type=URL;
                  URL="http://www.foo.com/file"

    Content-type: text/html
    Content-Transfer-Encoding: binary

    THIS IS NOT REALLY THE BODY!











Freed, et. al.              Standards Track