On 2008-04-12 10:46:06 +0100, said:

Hi All,

Sorry i've been a bit quiet, I have been listening.

My wife is being driven round the bend by BT Broadband toyal yahoos or
whatever they are called this month who every so often change someting
(like the name of their outgoing mail server! Without giving any
warning to their customers, or even to their outsourced Indian sub-
continent support droids.

The cynic in me would say that this policy will make them millions
from calls to their support lines!

Anyways, I have managed to get outgoing mail going a couple of weeks
ago by making sure Eudora was using the BT Internet account to login
to the smtp server, and i've fixed it again today by spending half an
hour in a maze of twisty little passages all different which is bt
yahoo's website and "verifying" my wifes connectfree account. I did
ring Connectfree's support at one point, but was very disappointed to
find that instead of the very knowledgeable northern lad i'd gotten
last time, I got someone in the punjab who answered the phone as
Tiscali tech support :+((

Anyways, the question!

At one point the BT support droid said "well in that case, Connectfree
will have to provide you with your own smtp server" Which got me to
thinging (OK, three questions)

1. Would running our own smtp server on one of our XP workstations
protect us from any further stupidity on the part of BT.

2. Would it just work with BT's network without any configuration on
their part, or would it open up another can of worms WRT getting it
verified or whatever.

3. Would I have to get Connectfree or any other organisation to
reconfigure anything?

4. How difficult is it to set up an SMTP server?

5. If it's worth going ahead does anyone here have any recommendations
for a particular product (pref free, definately to run on XP (yes, I
know i'd be better off building a lunix box, but the management won't
allow any more boxes in the house (no, not even in the loft or the
shed))).

OK, 5 questions :+))

Setting up your own SMTP server is ultimately the way of having
complete control of your mail services, but goes hand in hand with
having your own domain name as well.

However, there are some caveats.

- The ISP must allow incoming connections on TCP port 25 from any
address on the internet. They may block all incoming port 25
connections to prevent you from running your own server because they
want to control traffic or to lock you into the use of their service.

- They should allow outgoing TCP port 25 connections to any internet
address as well. That way, your SMTP server can delivr mail directly
to the SMTP servers of your addressees without going through the ISP's
server and potentially introducing unnecessary delays. It is possible
to set up your SMTP server to use theirs as an outgoing relay.

- If you are running some kind of router with NAT, you would need to
arrange either a DMZ address or a port mapping on the router such that
an incoming TCP/25 connection gets mapped to the machine running your
server. The implication of that, if you are going to run the SMTP
server on your workstation is that you are opening it up to DOS and
other attacks on port 25. If the server software that you choose has
some vulnerabilities, it may be possible for an attacker to screw up
your mail or launch an attack in some othe way compromising your
machine. Windows is not a particularly secure platform for running
network service applications, which is why many companies running
Exchange do so behind a front end Unix SMTP server rather than exposing
Exchange to the internet. XP workstation has the potential to allow
more vulnerabilities because as a nominal client side platform it is
not really intended to run services in any substantial way. In
effect you are trusting Microsoft (bad idea with anyhting involving
networking) and the quality of any SMTP server software.

- Your ISP may well be doing dynamic IP addressing. This is fairly
typical for budget connections. SMTP mail services require that if
you are running your own mail domain and server that you advertise the
address of your SMTP server in a DNS server for your domain. (search
for MX record). The original intent in the designs was that the
address should remain static for a long time. An ISP using dynamic
addressing may change it at any time although the better ones don't
unless you drop your connection. To get around this, there are
services such as DynDNS which will allow your computer or router to
update a DNS server if your IP address changes. This works reasonably
well except that it may take time for the changes to propagate to SMTP
servers wishing to send you mail. That can result in delays after
addresses change.

Provided that this connectivity is permitted by the ISP, you can run
your own server together with your own domain name. In effect, that
makes you independent of the ISP or mail and givs you easy portability
to other ISPs. A change of ISP wold only require address changes on
your side.

There certainly are SMTP servers around for XP workstation, which for
small use would probably be OK. I would select by reading reviews.
Linux is better as you say.

An alternative hosting approach would be to run virtual machines. If
you have a substantial enough machine, you could run VMware and put a
Linux virtual machine on Windows, or much better, host Windows as a VM
on Linux. This has a side advantage that you can recover your Wndows
environment very quickly when it inevitably breaks.


Having said all of this, a simpler solution to the whole issue may be
to find a mail and DNS hosting service separate from your ISP, register
a domain with it and use that for incoming and outgoing mail. Use of
this would depend on whether your ISP allows outgoing port 25
connections to servers outside their world and POP or IMAP connections
similarly. If they don't, then it's time to find another ISP.