SMTP Server

[Jesper Nielsen]

Hi all!

I am currently planning an e-mail service. The base core of the service will
simply be a MDaemon mail server with a modified WorldClient as the frontend.

Unfortuneately, MDaemon cannot add a footer to all outgoing mails (like "Get
a FREE 10GB mail account at..."), so I've thought of this:

MDaemon can be setup to use a so-called smarthost. If setup, MDaemon will
forward all outgoing mail to another SMTP server, which will then handle the
actual delivery to the intended recipient(s). This SMTP server, which will
be adding the footer and an extra Received: header, I want to write myself
in VB.Net.

But... I've never worked with such server solutions. Could anybody please
give me some hints and tips about this? And perhaps give me some links to
sites where I can read more about writing my own server applikation?

The application will probably be handling several ingoing and outgoing
connections at the same time, so this is also a "problem" that should be
accounted for.

I'd appreciate any help i can get.

 

[Cor]

Hi Jesper,

I would first take a look at BizTalk Server

Cor

 

[Jesper Nielsen]

I would first take a look at BizTalk Server

Not an option - far too expensive for this project.
Also, MDaemon Pro has already been purchased in an unlimited edition.

 

[CJ Taylor]

And open a new line of credit if your going with BizTalk.

 

[CJ Taylor]

Wait... waht the hell does biztalk have to do with Email?

 

[Jesper Nielsen]

Wait... waht the hell does biztalk have to do with Email?

Yeah - I was asking myself that exact same question...

 

[Cor]

Hi CJ,

Wait... waht the hell does biztalk have to do with Email?

Quiet easy, as far as I know .Net only supports only sending from SMTP
messages not a complete Email message system which Jesper ask for.

So the first thing what I would do when I had that problem was looking how
it was implemented in BizTalk

This is a little piece of the documentation.
BizTalk Server 2000 supports the following transport services:
HTTP
HTTPS
SMTP
File
Message Queuing
Application integration components (AICs)
Loopback

 

[CJ Taylor]

Yeah... but thats not what BizTalk is for...

May support it, but thats not the reasoning for using BizTalk.

 

[Cor]

???

Yeah... but thats not what BizTalk is for...

 

[CJ Taylor]

I'm saying, I would spend 25-50k to implement a BizTalk server to do email
routing...

 

[Cor]

I did not say that, when I look to something I seldom buy, did you not know
I am Dutch?

I'm saying, I would spend 25-50k to implement a BizTalk server to do email

routing...

 

[CJ Taylor]

No... that I didn't know. =) But after seeing your beer comment, I now
understand.

 

[Jesper Nielsen]

Quiet easy, as far as I know .Net only supports only sending from SMTP

messages not a complete Email message system which Jesper ask for.

What I want to do is to create an application (Windows Forms) that accepts
connections from my MDaemon server, reads the commands and message bodies,
parses these, adds a Received: header and the extra line to the message
body, and forwards the e-mail to the recipient's mail server.

I still cannot see, how BizTalk would help me with this forwarding, and how
I could possibly justify the purchase of a BizTalk license...

 

[Brian Henry]

you would have to built a SMTP service that recieves email and attaches that
line to it... its usaully a SMTP plug in for something like exchange server
or something else... im not sure how to do it in .net but we just
implemented one in REBOL

 

[Jesper Nielsen]

you would have to built a SMTP service that recieves email and attaches
that

line to it... its usaully a SMTP plug in for something like exchange server
or something else... im not sure how to do it in .net but we just
implemented one in REBOL

Well, all i need to do is write a server service that listens for new
connections on some port, receives the data from MDaemon, parses and
midifies the e-mails and, finally, forwards the e-mails to the intended
recipients.

What I need help with is how to write a server application that can handle
multiple connections at the same time... Which controls will I need to use,
etc..

 

[CJ Taylor]

Ah

I did the same thing to do a logistics test in college... Alright, I'm kinda
winging it right here because I did this a couple years ago and it was in VB
6. So .NET (even though I haven't played with this side at all yet) may be
inheritantly multi-threaded, multi-socketed...

Now to explain that.

Alright I had a server application that LISTENED for incoming connections on
a designated port number, (lets use 8000) for right now.

Now, there was no communication other than that, a connection would come in
on Port 8000 and instantly redirect it to another winsock connection on
another port that would then contact the client calling machine on a
specified port (I made that part of the packet that was sent on inital.)
The new winsock connection would then run the communication between the
client and the server. The only thing is assigning the ranges you want to
connect back and forth to.

So you may want to keep a pool of which sockets are taken and which ones
aren't. And limit based on that (I beleive FTP works this way).

Then, the server can keep listening for connections and spin off other
threads to handle the actual data transfer between the client and server.

Hope that helps,

-CJ

 

[Cor]

Hi CJ,

You wont believe it, but that sounds to a lot of code Crirus supplied in
this newsgroup a couple of weeks ago. Should be somewhere by searching it
was something as TCP.

Cor

 

[Arvel Hathcock]

Unfortuneately, MDaemon cannot add a footer to all outgoing mails (like "Get

a FREE 10GB mail account at..."), so I've thought of this:

Sorry for getting into this discussion so late. MDaemon *can* add
footers to all outgoing email. Check out the Content Filter. One of
the actions is "add footer to outgoing messages" or some such wording.

Arvel Hathcock
Alt-N Technologies