2. For archived-at to be useful by email clients generally requires
one or two of the following, in addition to the obvious client
support for the protocol and server support for the message format:
- mail archives that support IMAP access (or possibly NNTP)
- a specification for making collections of mail messages available
via HTTP (maybe WebDav) and/or FTP
- mail archives that follow the aforementioned specification
I don't think that the second item (http/ftp) is going to be
generally useful for email clients. Perhaps for combined
MUA/browsers, but at most there seems to be only a loose
connection between the browsers and MUA portions of those
(see below re. Mozilla).
having implemented HTTP and FTP client libs from scratch in a few
hundred lines of code each, I don't see either of these as onerous.
and there's an advantage in that for HTTP and FTP, "anonymous" access
is widely supported by servers.
I believe a great deal more is needed. I've mentioned lack of
URI support in MUAs and limited support of the most useful
URIs (imap) in browsers. Some details:
thanks for looking into this. none of what you found surprises me. I
didn't expect that many existing MUAs would be able to take advantage
of URIs pointing to archives without some upgrade. I do, however,
suspect that it's feasable to upgrade an MUA that already supports IMAP
to point to an IMAP archive of rfc822 messages, or even to upgrade an
MUA to be able to read an archive of 822 messages using FTP or
HTTP+WebDav.
right now I'm thinking in terms of writing an Informational or
Experimental RFC called "Recommendations for Net-Accessible Mail
Archives". It would describe how to set up archives, and also describe
how to use Archived-At to point to those archives. I'm thinking that
archives should be based on maildir at the server end, though for the
sake of efficiency I'm wondering about options to use mbox format
(yeech) and compression, and also how to avoid having several years'
worth of archives in a single directory or file while still making the
whole archive appear seamless to the client. Offhand it looks like FTP
is probably the most straightforward access method to implement, but
that it should be possible to define reasonable access via other
protocols also.
Keith