Some basic IMAP questions
Matt
My ISP only uses POP for mails and I have been doing it this way for
several years. I'm looking into getting an account from another provider,
possibly one using IMAP. I've read about the many advantages of IMAP so
don't need a primer. However I did have several questions for IMAP users:
Security: you are comfortable leaving your mails in plaintext,
indefinitely, on a server that you don't control? Sensitive documents
from financial institutions, credit card companies, etc.? Risque mails
to your girlfriend?
POP has the same issue, but to a lesser degree if you regularly download
and delete your mail from the server. Yes, it's true your computer can
still be stolen or accessed without your consent, but you have a greater
degree of control over those risks.
Quotas: Size seems a bigger factor with IMAP, since most providers don't
give you unlimited storage. With POP you are limited by your available
hard drive space, which is virtually no limit at all (though you have
to be careful about getting some very large attachments in a short time
before you can download them). With IMAP it seems like only a matter
of time before you will run out of space. Is the idea that you will
manually save important email and attachments while occasionally pruning
your mailbox to an acceptable size? I tend to save everything so that's
something I would have to adjust to. (I know Gmail gives you a
lot of space; I'm not considering Gmail right now).
"End of Life" - After some point you may decide you no longer wish to
use that IMAP provider. Then what do you do with your mail?
Thanks, I appreciate your comments.
{follow-ups to c.m.imap}
--
Matt
Grant Taylor
> Security: you are comfortable leaving your mails in plaintext,
> indefinitely, on a server that you don't control? Sensitive
> documents from financial institutions, credit card companies, etc.?
> Risque mails to your girlfriend?
I can see how that is a concern. However I can't comment on it as I run
multiple different IMAP servers (both personally and professionally) and
as such I have complete control.
> POP has the same issue, but to a lesser degree if you regularly
> download and delete your mail from the server. Yes, it's true your
> computer can still be stolen or accessed without your consent, but
> you have a greater degree of control over those risks.
*nod*
I think the main difference between IMAP and POP is that mail is stored
long term on the server where as it would other wise not be. So this
long term storage exposes much more of your email to a would be breach.
Typical S/MIME / PGP encryption techniques come to mind, but they
require support on the remote end, thus limiting their viability.
Ultimately you have to weight the features verses the risk.
> Quotas: Size seems a bigger factor with IMAP, since most providers
> don't give you unlimited storage. With POP you are limited by your
> available hard drive space, which is virtually no limit at all
> (though you have to be careful about getting some very large
> attachments in a short time before you can download them). With IMAP
> it seems like only a matter of time before you will run out of space.
> Is the idea that you will manually save important email and
> attachments while occasionally pruning your mailbox to an acceptable
> size? I tend to save everything so that's something I would have to
> adjust to. (I know Gmail gives you a lot of space; I'm not
> considering Gmail right now).
Disk usage is probably the *biggest* problem you will have. I do
primarily text (ASCII, not HTML) email with a few moderate attachments.
Over the better part of a decade I have crossed the 2 GB mark on my
email. Though, again when I run the servers this is not a problem. If
it was I probably would not maintain as much old (archive type) email,
i.e. copies of messages to / from public mailing lists and / or newsgroups.
> "End of Life" - After some point you may decide you no longer wish to
> use that IMAP provider. Then what do you do with your mail?
There is absolutely no reason that you can't download the contents of
your IMAP mail store to a similar folder structure on a local computer,
be it Thunderbird / Outlook / etc. Similarly, there is no reason why
you can't upload existing email to the server you are looking at. ;)
This upload / download ability of IMAP is probably one of the nicest
things that makes it possible to move email in between email clients
that would other wise not talk to each other. The only limiting factor
is 1) the speed of your connection to the IMAP server and 2) the quality
of the IMAP implementation and how quickly it can run.
> Thanks, I appreciate your comments.
*nod*
Grant. . . .
David F. Skoll
> Security: you are comfortable leaving your mails in plaintext,
> indefinitely, on a server that you don't control? Sensitive documents
> from financial institutions, credit card companies, etc.? Risque mails
> to your girlfriend?
So what? If your ISP wanted to, it could archive all your mail
without your knowledge, even if you use POP. If you are actually
worried about that, get people sending you sensitive mail to encrypt
them with PGP or GnuPG.
> Quotas: Size seems a bigger factor with IMAP, since most providers don't
> give you unlimited storage.
Yes. IMAP providers are going to be much stricter about enforcing
quotas. Unless you control the IMAP server, you're going to have to
clean your mailboxes regularly.
> "End of Life" - After some point you may decide you no longer wish to
> use that IMAP provider. Then what do you do with your mail?
There are tools to suck mail from one IMAP server and push them onto another
IMAP server. If you're UNIX-clueful, you can run your *own* IMAP server
and not be dependent on your ISP. Then you get the best of all worlds.
-- David.
Mark Hobley
> I think the main difference between IMAP and POP is that mail is stored
> long term on the server where as it would other wise not be. So this
> long term storage exposes much more of your email to a would be breach.
One approach is to have mail delivered to mailboxes hosted by the ISP. This is
then collected via POP3 and delivered to a local IMAP server. The clients then
connect to the local IMAP server to view the mail messages.
POP3 from the ISP
IMAP on the LAN
Mark.
--
Mark Hobley
Linux User: #370818 http://markhobley.yi.org/
Grant Taylor
> One approach is to have mail delivered to mailboxes hosted by the
> ISP. This is then collected via POP3 and delivered to a local IMAP
> server. The clients then connect to the local IMAP server to view the
> mail messages.
*nod*
This is how fetchmail and Exchange POP3 connectors work. They pull
email from one (or more) mail box(es) and deliver them to the local server.
This does work, but is not as nice as an end to end SMTP delivery path.
Further, this requires one (or more) account(s) on the ISPs server.
There are also some other options off the beaten path. Ask if you are
interested in hearing about them.
Grant. . . .
Andrzej Adam Filip
> Grant Taylor <gta...@riverviewtech.net> wrote:
>> I think the main difference between IMAP and POP is that mail is stored
>> long term on the server where as it would other wise not be. So this
>> long term storage exposes much more of your email to a would be breach.
>
> One approach is to have mail delivered to mailboxes hosted by the ISP. This is
> then collected via POP3 and delivered to a local IMAP server. The clients then
> connect to the local IMAP server to view the mail messages.
>
> POP3 from the ISP
> IMAP on the LAN
or "IMAP with IDLE" from the ISP (or e.g. gmail)
to get "no delays deliveries" without delays created by polling period
in case of POP3.
--
[pl>en Andrew] Andrzej Adam Filip : an...@onet.eu : Andrze...@gmail.com
"Tell the truth and run."
-- Yugoslav proverb
Grant Taylor
> or "IMAP with IDLE" from the ISP (or e.g. gmail) to get "no delays
> deliveries" without delays created by polling period in case of POP3.
Though a technically valid point, I think more than a few people would
get annoyed to mad at you doing that. If you are wanting that level of
""instant service, I'd strongly suggest you look at simply having SMTP
delivery directly in to your internal mail server.
Don't forget that your clients will have to similarly use IMAP IDLE to
see that their local server has email too. (Though I guess you could
have something use IMAP IDLE and push the messages to a group ware
server that supports notifications to clients.
Grant. . . .
Andrzej Adam Filip
> On 8/4/2009 3:49 PM, Andrzej Adam Filip wrote:
>> or "IMAP with IDLE" from the ISP (or e.g. gmail) to get "no delays
>> deliveries" without delays created by polling period in case of
>> POP3.
>
> Though a technically valid point, I think more than a few people would
> get annoyed to mad at you doing that. If you are wanting that level
> of ""instant service, I'd strongly suggest you look at simply having
> SMTP delivery directly in to your internal mail server.
IMHO: IMAP+IDLE is a better option for "one traveller", especially for
people using "gmail" anyway. I do not dare to suggest it is the best
solution in every case, I suggest it is an option worth to consider.
I have seen far too many people using POP3 with polling period short
enough to make postmaster unhappy/angry.
> Don't forget that your clients will have to similarly use IMAP IDLE to
> see that their local server has email too. (Though I guess you could
> have something use IMAP IDLE and push the messages to a group ware
> server that supports notifications to clients.
--
[pl>en Andrew] Andrzej Adam Filip : an...@onet.eu : Andrze...@gmail.com
The covers of this book are too far apart.
-- Book review by Ambrose Bierce.
Grant Taylor
> IMHO: IMAP+IDLE is a better option for "one traveller", especially
> for people using "gmail" anyway. I do not dare to suggest it is the
> best solution in every case, I suggest it is an option worth to
> consider.
If we are talking a single user, I agree that IMAP+IDLE would be a
decent way to get notified about new messages.
Though, I would question why a single user would even have a local IMAP
server rather than just using the remote IMAP server. (I guess there
are reasons though.)
Rather than doing things this way, I'd be tempted to look at an IMAP
sync program and seeing if it would be possible to extend it as a daemon
such that it would use IMAP+IDLE on both connections and then simply
replicate changes between IMAP servers.
> I have seen far too many people using POP3 with polling period short
> enough to make postmaster unhappy/angry.
As have I.
I've been known to threaten users if they check more than once every 5
minutes. Especially the ones that leave messages on the server, thus
causing more load for poor server implementations (that want to copy the
mail box and then lock one of them).
Grant. . . .
Andrzej Adam Filip
> On 08/05/09 02:16, Andrzej Adam Filip wrote:
>> IMHO: IMAP+IDLE is a better option for "one traveller", especially
>> for people using "gmail" anyway. I do not dare to suggest it is the
>> best solution in every case, I suggest it is an option worth to
>> consider.
>
> If we are talking a single user, I agree that IMAP+IDLE would be a
> decent way to get notified about new messages.
>
> Though, I would question why a single user would even have a local
> IMAP server rather than just using the remote IMAP server. (I guess
> there are reasons though.)
>
> Rather than doing things this way, I'd be tempted to look at an IMAP
> sync program and seeing if it would be possible to extend it as a
> daemon such that it would use IMAP+IDLE on both connections and then
> simply replicate changes between IMAP servers.
Some users may treat remote IMAP server (with slower access) as "the
permanent archive" and local IMAP server (with FAST access) as "the
working copy".
Such approach makes perfect sense with gmail storage size and search
capabilities [privacy protection levels granted by gmail (or other US
located services for non US citizens) are another story - I would not
myself trust it for anything sensivitive].
>> I have seen far too many people using POP3 with polling period short
>> enough to make postmaster unhappy/angry.
>
> As have I.
>
> I've been known to threaten users if they check more than once every 5
> minutes. Especially the ones that leave messages on the server, thus
> causing more load for poor server implementations (that want to copy
> the mail box and then lock one of them).
--
[pl>en Andrew] Andrzej Adam Filip : an...@onet.eu : Andrze...@gmail.com
Authors (and perhaps columnists) eventually rise to the top of whatever
depths they were once able to plumb.
-- Stanley Kaufman
Matt
> Matt wrote:
>
>> Security: you are comfortable leaving your mails in plaintext,
>> indefinitely, on a server that you don't control? Sensitive documents
>> from financial institutions, credit card companies, etc.? Risque mails
>> to your girlfriend?
>
> So what? If your ISP wanted to, it could archive all your mail
> without your knowledge, even if you use POP. If you are actually
> worried about that, get people sending you sensitive mail to encrypt
> them with PGP or GnuPG.
Unfortunately, I know too many people who are not concerned about
security or not technically inclined to be able to handle
something "new". And it's not so much that I think my ISP is
spying on me, but that in the event of a data breach there is
likely less volume of email exposed if I'm using POP than IMAP.
Appreciate your comments.
Matt
> On 08/03/09 15:16, Matt wrote:
>> Security: you are comfortable leaving your mails in plaintext,
>> indefinitely, on a server that you don't control? Sensitive
>> documents from financial institutions, credit card companies, etc.?
>> Risque mails to your girlfriend?
>
> I can see how that is a concern. However I can't comment on it as I run
> multiple different IMAP servers (both personally and professionally) and
> as such I have complete control.
I should have clarified at the outset that I'm writing from a
"laptop home user" perspective and that running my own server isn't
really in the cards.
> I think the main difference between IMAP and POP is that mail is stored
> long term on the server where as it would other wise not be. So this
> long term storage exposes much more of your email to a would be breach.
>
> Typical S/MIME / PGP encryption techniques come to mind, but they
> require support on the remote end, thus limiting their viability.
>
> Ultimately you have to weight the features verses the risk.
Ok, that's what I thought. I think I will have to just get a free account
somewhere to test it out and see how I like it. What would be nice is if
the IMAP provider could encrypt mails using your public key so that only
you could read them... even though they were transmitted in cleartext,
they would be archived securely. Although I can see why they wouldn't do
this, as it could seem to be a tacit admission that they can't be trusted.
> Disk usage is probably the *biggest* problem you will have. I do
> primarily text (ASCII, not HTML) email with a few moderate attachments.
> Over the better part of a decade I have crossed the 2 GB mark on my
> email. Though, again when I run the servers this is not a problem. If
> it was I probably would not maintain as much old (archive type) email,
> i.e. copies of messages to / from public mailing lists and / or newsgroups.
I think it's the big attachments that get you. I know some mail clients
will let you strip attachments from messages, since you might just want
an archive of the message and have saved or don't need the attachment. Do
you know if this would work with IMAP as well? Can't see why it wouldn't.
>> "End of Life" - After some point you may decide you no longer wish to
>> use that IMAP provider. Then what do you do with your mail?
>
> There is absolutely no reason that you can't download the contents of
> your IMAP mail store to a similar folder structure on a local computer,
> be it Thunderbird / Outlook / etc. Similarly, there is no reason why
> you can't upload existing email to the server you are looking at. ;)
Ah, good news. I've used IMAP but am not that familiar with its
functionality. Thanks again for the comments.
--
Matt
Matt
> On 08/03/09 18:08, Mark Hobley wrote:
>> One approach is to have mail delivered to mailboxes hosted by the
>> ISP. This is then collected via POP3 and delivered to a local IMAP
>> server. The clients then connect to the local IMAP server to view the
>> mail messages.
>
> This is how fetchmail and Exchange POP3 connectors work. They pull
> email from one (or more) mail box(es) and deliver them to the local server.
Straying a bit from my original topic, why does fetchmail have
IMAP support? Is it related to what you say above, to download
mail for use on a local server? Because it always seemed
redundant to use fetchmail when the mail client could just
directly interact with the IMAP server.
--
Matt
Grant Taylor
> Straying a bit from my original topic, why does fetchmail have IMAP
> support? Is it related to what you say above, to download mail for
> use on a local server? Because it always seemed redundant to use
> fetchmail when the mail client could just directly interact with the
> IMAP server.
It may be redundant to fetch from one IMAP server and post them to
another, but it is not redundant to fetch mail from an IMAP server and
then inject it in to another non-IMAP server, say via SMTP. I.e. to
pull mail from an ISP and send it in to a local Exchange (like) server.
Remember that fetchmail is an ever growing utility that aims to have as
much utility as possible, even if some of it's modes of operation may
seem silly when used with each other.
There is also the fact that you could use fetchmail to copy messages in
mass from one account to another, even on th same server.
Grant. . . .
Matt
> There is also the fact that you could use fetchmail to copy messages in
> mass from one account to another, even on th same server.
I think earlier you had mentioned IMAP makes it easy to download
a mailbox and upload it to another; is this something that
fetchmail would be really good for here? Or is it just as easy
with a typical mail client (e.g., mutt, what I'm using)?
--
Matt
Grant Taylor
> I think earlier you had mentioned IMAP makes it easy to download a
> mailbox and upload it to another; is this something that fetchmail
> would be really good for here? Or is it just as easy with a typical
> mail client (e.g., mutt, what I'm using)?
I think the "good for" is up to each individual's discretion. If you
routinely use fetchmail as a Swiss Army Knife then having that feature
is a good thing for the odd chance that you need it. If you want to
routinely sync a pair of IMAP mail boxen, other tools may be better.
Your mileage may vary.
Yes I have used a typical IMAP client (Outlook Express) to migrate
contents from an old IMAP server to a new IMAP server and it did work.
However taking the time to re-configure each (new and old) account for
each client was annoying. If I had needed to do more accounts than I
did I certainly would have looked for a tool that would have been more
scripted and did not require manual interaction.
I guess it really does vary on what your needs are.
Grant. . . .
Matt
> I guess it really does vary on what your needs are.
Ok, thanks again for all your comments. :)
--
Matt
Thor Kottelin
news:OAHdm.401$nh2...@nwrddc02.gnilink.net...
> I did have several questions for IMAP users:
>
> Security: you are comfortable leaving your mails in plaintext,
> indefinitely, on a server that you don't control?
If it is sensitive, it should be encrypted in the first place. If the
message can be sent all over the place using SMTP, storing it on the
server of a provider you have chosen is probably not much of an issue.
> Quotas: Size seems a bigger factor with IMAP, since most providers don't
> give you unlimited storage. With POP you are limited by your available
> hard drive space, which is virtually no limit at all (though you have
> to be careful about getting some very large attachments in a short time
> before you can download them). With IMAP it seems like only a matter
> of time before you will run out of space. Is the idea that you will
> manually save important email and attachments while occasionally pruning
> your mailbox to an acceptable size?
Good email client software makes it easy to automatically archive mail on
a local disk, a network disk, or the null device, as appropriate.
> I tend to save everything
This is often a good idea.
> "End of Life" - After some point you may decide you no longer wish to
> use that IMAP provider. Then what do you do with your mail?
Download it, or move it to another server.
--
Thor Kottelin
http://www.anta.net/
Grant Taylor
> Ok, thanks again for all your comments. :)
*nod*
Grant. . . .