SMTP l basics

[rvj]

1. Can anyone suggest some "light" reading why we use SMTP to point to a
relay server that then redirects your email to the intended mail exchange

RATHER THAN

send the message DIRECTLY from the client email package to the intended
mail exchange?


It cant be client side performance overload since the email is only
outgoing !


2. I presume the same host can be used for POP3 and SMTP - but is it
advisable - any guidelines?

 

[Charlie Tame]

1. Can anyone suggest some "light" reading why we use SMTP to point to a
relay server that then redirects your email to the intended mail exchange

RATHER THAN

send the message DIRECTLY from the client email package to the intended
mail exchange?


It cant be client side performance overload since the email is only
outgoing !


2. I presume the same host can be used for POP3 and SMTP - but is it
advisable - any guidelines?

1, does this help?

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

I guess the convention is quite old and it was probably deemed more
reliable to have messages pushed to a known "Always on" machine which
could perform retries etc if for some reason the eventual destination
server was having a bad day? In any case this was more than likely a
dedicated machine on the local network within the business, and probably
quicker in the early days.

2. seems to work fine for me, I guess volume might be a factor but with
modern machines as fast as they are you probably won't have to worry
about that.

I have not done anything like this with MS software, I have used Debian
Linux and webmin to administer things, so can;t help with specifics.

 

[Earle Horton]

It's the same reason you use the postman to deliver your mail to the post
office or distribution center, who then sends it via truck or airplane to
another distribution center, who then sends it via a third courier to the
intended recipient. This is better for volume, and takes care of the
eventuality that the recipient is not home when you call. You could of
course hire a courier service to carry your letter directly across town or
across the country, but it would cost more. And eventually the courier
services wind up using relays too to save themselves money. This is also
the same reason that many of us use voice mail. It is so much more
convenient than trying to play telephone tag.

If you don't think it is efficient, then try this experiment. Try to
contact a co-worker using an instant messenger or chat program on her day
off.

Earle

 

[Gary VanderMolen]

What you suggest (direct to MX) sending was initially allowed,
but due to the ever increasing spam problem, it was outlawed.
Destination mail servers no longer accept mail directly from
individual senders, it must be sent through a recognized and
legitimate mail server.