Re: XML and Objects

John Cowan (cowan@locke.ccil.org)
Mon, 28 Sep 1998 10:57:54 -0400


David Megginson scripsit:

> I don't think that you need a CDATA section with Base64 (can someone
> confirm that Base64 excludes '<' and '&'?).

I confirm it. Base64 has 65 characters: A-Z, a-z, 0-9, +, -, and =,
the last of which is used for padding purposes when the binary
is not a multiple of 3 bytes (Base64 is basically a 3-byte binary
to/from 4-byte ASCII conversion).

Authoritative information is available in RFC 2045, clause 6.8.

> > * Wrap the document in a multipart/related MIME message
> > and include the content as attachments
>
> This sounds like a wise choice. XML packaging is a problem that the
> W3C XML Activity has not yet addressed -- experimentation and
> implementation experience will be very helpful to them when the time
> comes (after all, that's one of XML-DEV's greatest strengths).

One advantage of multipart/related is that there is a standard
URL format for referring from one part of a multipart message to
another. Each part can have a Content-ID: header, analogous to
the overall Message-ID: header, and then an URL of the form
"cid:xx7f9weURV@whoever.com" can refer to the part with that
header. See RFC 2111.

-- 
John Cowan	http://www.ccil.org/~cowan		cowan@ccil.org
	You tollerday donsk?  N.  You tolkatiff scowegian?  Nn.
	You spigotty anglease?  Nnn.  You phonio saxo?  Nnnn.
		Clear all so!  'Tis a Jute.... (Finnegans Wake 16.5)