On Saturday, April 29, 2006 @ 6:20 AM, Hylton Conacher wrote:
Greg Wallace wrote:
On Thursday, April 27, 2006 @ 9:33 AM, Hylton Conacher wrote:
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OK, so , assuming a mail has to take the long path to get to the email destination and therefore goes from local SMTP to ISP SMTP to intermediary SMTP to destination SMTP and that the intermediary SMTP needs authentication. However because it cannot see my local server, due to it having dropped its dialup connection or whatever, it does other tests to obtain authentication.
If you send mail to a 3rd party SMTP while logged into your local ISP, your local ISP SMTP server doesn't even get involved. Maybe I'm misreading your above paragraph, but it sounds like you might be thinking it does get involved. Sorry Greg, a slight mis-read/misunderstanding on your/my side. As I understand an SMTP server must send its load to another SMTP server. To clarify let us assume there are only 3 SMTP servers in the world ie my local one, my ISP's one, the destination one.
Me-- |A|----------Broken link--------------|B| \ / \---------Link OK-------|C|--------/
Me=My Mozilla-mail on my local machine A= My local SMTP server B= Destination SMTP server C=My ISP SMTP server acting as relay between A and B
Let us assume that A cannot see the destination B. It determines that the alternate path to B is via C.
The destination (B) does not need to authenticate the messages it receives however C does. So while my local SMTP server is connected and sending mail to C, C does authentication and sees that the FROM header in some of the emails is not the same as the email address as the person logged onto the ISP. C therefore drops those messages into the forever ether. The messages whose FROM header is the same as the person dialed in are relayed to the destination server (B).
Can the above happen to a local SMTP server (A) as it has been happening to Me when I sent email directly from my Mozilla Mail to C. If the FROM header in some of the emails is not the same as the email address as the person logged onto the ISP. C therefore drops those messages into the forever ether. The messages whose FROM header is the same as the person dialed in are relayed to the destination server (B).
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I hope the above better explains my concerns.
Hylton: In my case, I use a 3rd party SMTP server, not my ISP's. That being the case, the fist SMTP server to get involved with my email is this 3rd party SMTP. There is no SMTP server before that. From your description, it sounds like you have an SMTP server on your machine as well. If I use my ISP SMTP server, that would be the first SMTP server that I hit. So, I either use the 3rd party SMTP server or my ISP's SMTP server. There is no SMTP server involved in the transmission to that point. Now after it leaves that SMTP server and heads to the destination server, I take it that there can be relays in between involving additional SMTP servers, at least that's how I understand it. Greg Wallace