Email Without Port 25

Bill Desjardin (11/17/08 2:00PM)
Bill Desjardin (11/17/08 4:16PM)
Lee Hinde (11/17/08 4:22PM)
4D, Inc. (11/17/08 4:23PM)
Kevin LaTona (11/17/08 4:56PM)
Mehboob Alam (11/17/08 5:30PM)
Mehboob Alam (11/17/08 5:33PM)
Kevin LaTona (11/17/08 6:42PM)
Chip Scheide (11/18/08 10:43AM)


Bill Desjardin (11/17/08 2:00 PM)

Hi all,

I currently have a 4D app running at a large company and it sends  

email using the SMTP capabilities of the Internet Commands plug-in.   

The emails are going to a gateway for ultimate delivery to Lotus  

Notes clients.  Unfortunately, the IT people consider it a security  

issue to have port 25 open.  So, does anybody have any ideas on  

delivering emails to Lotus Notes clients without using port 25?  Is  

there an API to go directly to the Notes server, rather than using  

the SMTP gateway?

Bill Desjardin

Bill Desjardin (11/17/08 4:16 PM)

Josh,

Thanks for the enlightenment.  I will definitely ask the question.  I
 

don't have control over the SMTP gateway, however, and it uses port  

25.  If I can get IT to agree on some other port for my sending of  

SMTP traffic, does that mean a change only on my end, or on the  

gateway end as well?

Bill Desjardin

On Nov 17, 2008, at 3:54 PM, Josh Fletcher (4D, Inc.) wrote:

Hi Bill,

You can use any port you want for any TCP/IP technology but that port

must be open across the entire connection, or redirected.

The assertion that port 25 being open is a security issue is somewhat

fallacious.  A port has to be open, period.  A port scanner can  

identify

open ports.  Ergo  the choice of port is irrelevant in terms of  

someone

hacking the system.

The only assumption that having port 25 open gives the hacker is that

it's being used for SMPT but that does not *have* to be true.

At any rate it really doesn't matter :)  The IT department needs to  

tell

you what port you *can* use if you are not allowed to use 25.

-Josh

Bill Desjardin wrote:

Mehboob,

Do you mean that I can use any port I wish for SMTP, regardless of

the port being used by the gateway?  I was asssuming that both ends

of the SMTP traffic had to use the same port.

Bill Desjardin

--

Josh Fletcher

Technical Services Team Member

4D, Inc.

Lee Hinde (11/17/08 4:22 PM)

<d959f9b30811171622i191eedf8n713eb4c4438e1cf4@...

Bill

There would need to be a change on the gateway side as well. Whatever

port you send out on has to correspond to a receiving port. That

receiving port need not be the final actor, however, so you could

theoretically insert a port forwarder (you send out on port 26, the

message is receive on port 26 and redirected to port X.)

On Mon, Nov 17, 2008 at 4:16 PM, Bill Desjardin <bill@...
wrote:

Josh,

Thanks for the enlightenment.  I will definitely ask the question.  I
don't

have control over the SMTP gateway, however, and it uses port 25.  If
I can

get IT to agree on some other port for my sending of SMTP traffic,
does that

mean a change only on my end, or on the gateway end as well?

Bill Desjardin

On Nov 17, 2008, at 3:54 PM, Josh Fletcher (4D, Inc.) wrote:

Hi Bill,

You can use any port you want for any TCP/IP technology but that port

must be open across the entire connection, or redirected.

The assertion that port 25 being open is a security issue is somewhat

fallacious.  A port has to be open, period.  A port scanner can
identify

open ports.  Ergo  the choice of port is irrelevant in terms of
someone

hacking the system.

The only assumption that having port 25 open gives the hacker is that

it's being used for SMPT but that does not *have* to be true.

At any rate it really doesn't matter :)  The IT department needs to
tell

you what port you *can* use if you are not allowed to use 25.

-Josh

Bill Desjardin wrote:

Mehboob,

Do you mean that I can use any port I wish for SMTP, regardless of

the port being used by the gateway?  I was asssuming that both ends

of the SMTP traffic had to use the same port.

Bill Desjardin

--

Josh Fletcher

Technical Services Team Member

4D, Inc.

4D, Inc. (11/17/08 4:23 PM)

Hi Bill,

Who owns the "gateway" you're referring to?  If it's the complaining
IT

department, they'll have to configure it.

If it's, say, your ISP, you'll have to contact them.

But, in general, there will probably be some extra configuration
besides

your 4D code.

Also note that I'm intentionally not addressing your question about

Lotus because I do not know what solutions might be out there...it's a

good question, is there a "native" API?  Perhaps others will be able
to

help with that.

-Josh

Bill Desjardin wrote:

Josh,

Thanks for the enlightenment.  I will definitely ask the question.  I
 

don't have control over the SMTP gateway, however, and it uses port  

25.  If I can get IT to agree on some other port for my sending of  

SMTP traffic, does that mean a change only on my end, or on the  

gateway end as well?

Bill Desjardin

--

Josh Fletcher

Technical Services Team Member

4D, Inc.

Kevin LaTona (11/17/08 4:56 PM)

Bill,

On Nov 17, 2008, at 3:45 PM, Bill Desjardin wrote:

Are you suggesting that I can send SMTP mail directly to a Notes  

server?

Yes, As long as they stick to rfc standards you will have no problem  

talking to a Notes server.

I'm not an expert on Notes

But it appears to be nothing more than IBM's version of a email  

server, IMC, wiki, etc., etc. all rolled together into a client  

server Document-oriented database.

http://en.wikipedia.org/wiki/IBM_Lotus_Notes

I think you will be fine once you know what port to talk with.

Kevin

Mehboob Alam (11/17/08 5:30 PM)

Bill,

Here's some additional information.. SMPT's default port is 25.. the
implied "security" issue may be that that the port could be used as an
open relay by spammers.. BUT only if it's left configured that way.

Look at the "advanced" section in the AppleMail client, and it
specifies the following as default ports for SMPT: 25, 465 and 587..
OR the option to use a custom port number.

The preferred port now is apparently 587

http://www.pcmag.com/article2/0,2817,1838667,00.asp

So, you can use any number, as long as the SMTP server is configured
to also listen on that number. If the server is currently set to 25,
and the IT department plans to change that, they'll be busy
reconfiguring most of their email clients too.. except for the Lotus
Notes client, which use MAPI to communicate with the email server.

Do not, under any condition allow the IT department to talk you into
using SSL as another security measure, as far as I know, 4DIC
currently does not support sending using SSL.

sincerely,

mehboob alam

To make a bad day worse, spend it wishing for the impossible.

--- On Mon, 11/17/08, Bill Desjardin <bill@... wrote:

From: Bill Desjardin <bill@...

Date: Monday, November 17, 2008, 6:42 PM

Mehboob,

Do you mean that I can use any port I wish for SMTP,

regardless of the port being used by the gateway?  I was

asssuming that both ends of the SMTP traffic had to use the

same port.

Bill Desjardin

Mehboob Alam (11/17/08 5:33 PM)

No, you should not try to send the email directly to Lotus Notes..
unless you know how to implement the MAPI protocol in 4D.. which you
can't really.

Stick to SMTP, agree on what port number you should send to, and
you're done.

Here's more about Notes and MAPI

http://www.slipstick.com/addins/services/lotusnotes.htm

sincerely,

mehboob alam

To make a bad day worse, spend it wishing for the impossible.

--- On Mon, 11/17/08, Bill Desjardin <bill@... wrote:

From: Bill Desjardin <bill@...

Date: Monday, November 17, 2008, 6:45 PM

Kevin,

Are you suggesting that I can send SMTP mail directly to a

Notes server?

Bill Desjardin

Kevin LaTona (11/17/08 6:42 PM)

Bill,

I would have to agree with Mehboob Alam that if you have to use the  

MAPI api this it turning into a huge task for you.

But I always say anything is possible in 4D --> if you have the time  

and money to pull it off.

Getting back to square one you stated they have a SMTP gateway.

My question for them and you would be how does this company expect to  

talk with anyone off their internal Note's network if they don't go  

thru this SMTP gateway?

If they want to change this SMTP port number to whatever other than  

Port 25,

it really doesn't matter to you so long as you know what the New port  

is and adjust for it as we all stated in the first emails.

The company certainly is not suggesting  dumping this SMTP gateway  

are they?

--

Kevin

Chip Scheide (11/18/08 10:43 AM)

NO -

the ISP (or other mail provider) has to tell you what port(s) they

support

On Mon, 17 Nov 2008 15:54:29 -0800, Josh Fletcher (4D, Inc.) wrote:

At any rate it really doesn't matter :)  The IT department needs to
tell

you what port you *can* use if you are not allowed to use 25.

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Summary created 11/18/08 at 10:37AM by Intellex Corporation

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