On Fri, 2 Sep 2005, Adam Funk wrote: > Since many of you believe that residential customers should be > forced to route all their mail through their ISPs' smarthosts,
There's something in what you say, but there are a couple of detailed points that I would take issue with in that paragraph. The reality of the current situation is that we simply cannot *afford* to accept mail directly from random IPs, such as those provided by domestic ISPs, that have not been set up as properly supported mail systems. It isn't that we think they "should be forced", but that there's a great quagmire of compromised domestic IPs out there, which make our decision, frankly, inevitable. And it isn't that they should necessarily have to use *their ISP's* mail relay. Just that they need to submit their mail via /some/ managed and generally trustworthy mail relay. Some domestic ISPs are maybe best treated as IP-only providers, whose users would be advised to submit their mail via some *mail service provider* with which they hold a mail account. One big ISP in the UK, in fact, operates mail smarthosts which are a long-standing festering source of Nigerian 419-style scams - to the extent that quite a few of us apply RBL rules under which that particular ISP's smarthosts are blocked for spamming. So if *they* are your ISP, then using their mail relays is going to cause you nothing but trouble, I'd say: you'd best look for some other mail service provider. > I think it follows that ISPs have a duty to provide reliable > outgoing SMTP to their customers. I don't think it does. I'd say, however, that ISPs generally *do* have a duty not to block or capture the mail submission protocols - leaving the customer an open choice of mail service provider. Not to be confused with SMTP on port 25, which they might care to block or capture to offer some protection from the risks of direct-to-MX abuse lest the customer gets infested by some virus/trojan.[1] > My ISP however claims that "The e-mail is a free service provided by > us and therefore no compensation can be offered for downtime of this > service." IANAL, but if the service is bundled with the rest of their account offering then it is not "free", but you'd have to check their T&Cs. Nevertheless, it does help to explain why I'm recommending mail submission via some well-supported mail system, which might be with an unrelated provider; as an example, we recommend *our* users to submit their mail from home via their University mail server account, using the authenticated mail submission arrangements which we support. Looking at this from the other side, we've had several complaints recently from the USA where senders were presenting their own .gov envelope sender addresses (relating to research institutions in the USA), but the offering IP, as seen by us, was their home IP address at some spam-ridden residential ISP, and we were rejecting the mail out of hand for that reason -- after all, any spammer can fake a .gov address as envelope sender - and lots of them do so - but relatively few can submit their mail so that it's offered to us from an IP which resolves to a .gov address! As a second best, we would still accept their mail from a reliable mail service provider (i.e not too heavily blacklisted at the usual dnsRBLs) - which might or might not be the same company as provides their broadband IP service or whatever. best regards [1] I do worry, however, about the possibilities of viruses/trojans which have worked out how to drive the user's authenticated mail submission protocols, instead of the dumb SMTP engines that most of them used till now. -- ## List details at http://www.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://www.exim.org/eximwiki/
