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Re: NDNs considered harmful

2010-08-12 13:54:16

Paul Smith wrote:

Well, if we were the ISP we could - but we're not... The ISP could be anyone - we do the end-user mail server software.

(I'm not asking for a solution really - just saying that the 'NDN' issue isn't that easy - if an upstream ISP blocks outgoing port 25 (blocking sending using MX routing), and then blocks all outgoing mail because of 'spam' (NDNs) then you have no choice but to not send NDNs).

I'm not sure I follow. ISP have more "power" when it comes to "Users", and if is blocking port 25, then this generally implies a home, non-business tier account. If its was a business tier, an ISP blocking your mail service is open to Tortious Interference (business interruption) claims.

(NB - We try to encourage users to switch to incoming SMTP if possible because then an SMTP reject happens, but if they have dynamic IP addresses it won't work, or if they are are technically incompetent (many are) then even just opening up a port in a firewall to allow SMTP in is not possible.)

We still have many of the low-end, ex-BBSers sysops who have home setups or home business setups with home ISP accounts.

Many use the DynaDNS or whatever you call it stuff and I generally try today to avoid their support issues because its nothing but headaches trying to get them to be satisfied with trying to setup a real mail server operation. Delays, throttling, tarpitting, proxies, etc, is always an issue with them. Seems to work fine one moment and puff, its back to problems. Not very reliable.

What we are doing now is basically giving them PORT 587 and ESMTP AUTH outbound MTA sender features and I am doing so reluctantly. Before we relied on prearranged allow IP relay, smart hosting PORT 25 outbound only. The growth of these SOHO is high though. Many are moving/starting businesses are home and ISP business fees are higher.

I suspect this is going to help this smaller market, but highly loyal customer base, however, its going to be interesting to see how the their ISPs are going to react to this or if its going to improve the networking. I suspect it will - probably as a short term.

--
Sincerely

Hector Santos
http://www.santronics.com