Outgoing SMTP Servers

Bjørn Mork bjorn at mork.no
Thu Oct 27 07:10:43 UTC 2011

Mark Andrews <marka at isc.org> writes:
> In message <4EA8A021.9000805 at blakjak.net>, Mark Foster writes:
>> Why? It's a reasonable position; end users in the generic sense are
>> sending to whatever their client has set up for SMTP, fire-and-forget.  
>> Again, I feel like folks are taking their relatively complicated
>> use-cases and treating them as the norm.
> It's ths whole attitude that end users are incapable on doing thing
> correctly.   Most user are prefectly fine with having their mail
> go through a ISP's servers but there are exceptions and when people
> start say "only a ISP can do this" or "only business need this" by
> BS detector goes off because individuals do need to do the same
> sorts of things.

Yes.  Moving behind the BS, it's most likely a well calculated
difference between designing a product for 99% of the users or going for
the full 100%.  The problem is that some of the less technical ISP staff,
who often are involved in product definitons or financial and marketing
decisions, will think that 99% is "everyone" :-)

FWIW, we've been running a 25/tcp filter by default for a few years now,
offering a knob to turn it off from the start.  The knob is one of very
few settings the users are offered in their self-service web UI, along
with "change my password", "upgrade my account" and similar.  Disabling
the filter is of course free of charge. And when initially enabling the
filter, all users were informed about the possibility to turn it off.

Current status is that approx 1% of our users have disabled the filter
so far.  I assume most of them did so because they actually need access
to port 25/tcp, but some may have just turned it off to see what
happened and forgot about it. Filters will rarely be enabled again when
first disabled, as disabled filters naturally are unnoticable. This
makes the number of users disabling any given filter service aggregate
over time.

Anyway, that's the number we see. YMMV

Whether that 1% of users are important to you or not will probably
depend on a lot of factors.  But I believe it's safe to say that those
users can be classified as "power users", who will have a much higher
tendency to buy more expensive products and to discuss their their ISP
experiences with other power users.  This makes them a lot more valuable
than the number itself would indicate.


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