Re: Current status?

In article <g9r0lf$g15$1@xxxxxxxxxxxxxxxxx>,
david20@xxxxxxxxxxxxxxxx writes:
In article <7h%vk.609$393.335@trnddc05>, John Santos <john@xxxxxxx> writes:
Bill Gunshannon wrote:
In article <g9pl82$lh7$4@xxxxxxxxx>,
helbig@xxxxxxxxxxxxxxxxxxxxxxxx (Phillip Helbig---remove CLOTHES to reply) writes:

In article <t_Wvk.2076$U5.1028@xxxxxxxxxxxxxxx>,
=?ISO-8859-1?Q?Jan-Erik_S=F6derholm?= <jan-erik.soderholm@xxxxxxxxx>
writes:



Yup. I think that many of the problems arise because MUAs use the same
protocol (SMTP) and port (25) to send mail to MTAs as MTAs use to relay
mail to each other.

Modern MTAs can be configured to allow mail clients to submit mail to them on
the mail submission port (port 587) rather than port 25. See RFC 2476
http://www.faqs.org/rfcs/rfc2476.html

What does this buy you? You would still need to know who your MTA is
andc it would still need to be willing to accept email from you. It is
all the silly little notification apps that wree brought up here as
justification for allowing anybody to use port 25. They have no builtin
method of authenticating so the port number used changes nothing. I
certainly would not accept email on my MTA from someone on port 587 that
I would not also accept on port 25. The purpose of port 587 sand RFC
2476 is noto to control SPAM it is to make sure outgoing email meets
the proper formating requoirements of the other RFC's.



On the other hand MTAs talk to MUAs (when delivering
mail) using either of 2 different protocols (that I know of), POP3 on
port 110 and IMAP on port 143. (I don't think anything does POP2 on
port 109 any more.)

Logically there are three parties involved not two.
MTA, MUA and Message store.

Not sure what you make as differnt with "Message store". Unless you
are separating the guy MTA from the machine that runs POP or IMAP.
I don't see that as necessarily being a separate Email function although
it is possible and may even have some utility on a big enough system.


The MTA delivers mail to another MTA or to a message store.
The MUA originates mail and sends it to a MTA.
Mail clients generally incorporate the above MUA functionality together with
the ability to display and manipulate mail in the message store.

POP and IMAP are protocols used to access and manipulate the message store.
They are NOT used to deliver mail to the message store.

Agreed, but the "Message Store" is not necessarily even a part of the
Email system and I don't believe it has ever been considered by IETF.
I have users who use NFS to read their email. Does that make NFS an
Email Protocol, too? And, of course, Wessage Store is also irrelevant
to the problem of how to get the email system to be more immune to SPAM.


Note.

The SMTP servers which come with the TCPIP stacks (TCPWARE, MULTINET or TCPIP
SERVICES/UCX) are NOT fully fledged modern MTAs. For that you would need either
PMDF or MX.
(
PMDF is a commercial product but is available free for hobbyist use.
MX is now an open-source free product see
http://www.madgoat.com/
However I'm not aware of anyone currently continuing development of MX.
)


Maybe so, but if people played by the rules, basic SMTP is more than adequate
to the task. If ISP's blocked port 25 for all machines in their domain other
than their MTA I would need to filter incoming ports on my end. And RBL's
would rapidly become redundant.

Sadly, we are forced to spend a lot of time effort and technology trying
to, once again, solve a social problem. A social solution would work a
lot better.


bill

--
Bill Gunshannon | de-moc-ra-cy (di mok' ra see) n. Three wolves
billg999@xxxxxxxxxxxxxxx | and a sheep voting on what's for dinner.
University of Scranton |
Scranton, Pennsylvania | #include <std.disclaimer.h>
.

Relevant Pages

  • Re: Current status?
    ... You would still need to know who your MTA is ... justification for allowing anybody to use port 25. ... Not sure what you make as differnt with "Message store". ... Email Protocol, too? ...
    (comp.os.vms)
  • Re: Current status?
    ... justification for allowing anybody to use port 25. ... MTA, MUA and Message store. ... the ability to display and manipulate mail in the message store. ... Email Protocol, too? ...
    (comp.os.vms)
  • Re: Current status?
    ... You would still need to know who your MTA is ... justification for allowing anybody to use port 25. ... the ability to display and manipulate mail in the message store. ... Email Protocol, too? ...
    (comp.os.vms)
  • Re: Current status?
    ... You would still need to know who your MTA is ... justification for allowing anybody to use port 25. ... In order for SMTP mail to function your MTA has to accept connections on port ... Not sure what you make as differnt with "Message store". ...
    (comp.os.vms)
  • Re: Current status?
    ... You would still need to know who your MTA is ... justification for allowing anybody to use port 25. ... In order for SMTP mail to function your MTA has to accept connections on port ... Not sure what you make as differnt with "Message store". ...
    (comp.os.vms)