Terry,
Terry Gray wrote:
In contrast, I suspect that most enterprises use either
Exchange/MAPI or an IMAP-based solution (and of course
Exchange also supports IMAP).
This is not the picture that I see. I think that I would have made the
same assumption you did (why bother using POP3 when your server supports
IMAP) but that's not the way it works.
In Enterprise networks using GroupWise or Notes or Exchange, a good 80%
to 100% of the clients are using the client software that pairs with the
server software. So there is a GroupWise client, a Notes client and
there used to be an Exchange client but now everyone uses Outlook. This
is the setup that the helpdesk can support.
Although it might appear surprising, these other 10% or 20% of users
that don't use the native client that came with the server software (for
example, a Unix machine on an Exchange server, a Macintosh on a Notes
server, or a user loosely related to the Enterprise located in the
middle of nowhere) don't use IMAP but do use POP3, and I think it has to
do mostly with IT not wanting to support fancy configurations and yes
MAPI is fancy compared to POP3. The way IT typically sees these machines
is that they are a major support pain.
From a manageability/supportability standpoint, it is not a good idea to
configure an IMAP4 client to access an Exchange server when you can have
Outlook.
There are indeed some enterprises that have a Unix-based mail system
accessed by the crowd of Windows clients; however I think these are
massively over-representated in the IETF compared to the general
population.
Michel.