agsteele Posted January 31, 2006 Share Posted January 31, 2006 Please don't do that. Those messages don't cause misdirected bounces, most of them probably ARE bounces. Domains whose mailservers refuse those messages in violation of RFCs 821, 2821, 2505, and 1123 are subject to listing by dsn.rfc-ignorant.org - see Listing policy for dsn.rfc-ignorant.org zone for details.39853[/snapback] Hi Jeff! You are, of course, correct about the RFC - although I think when were dumping messages from null senders we were probably ignorant of the RFC concerned. But being slightly provocative, I wonder what the difference is between me deciding to reject all Email from a particular IP address and deciding not to accept Emails because they do not declare a sender address. If we argue that it is the right of the recipient to reject anything they prefer not to have passing through their server then do we not have a right to reject messages from null senders? I'm not looking for an argument - just posing the question... Andrew Link to comment Share on other sites More sharing options...
Jeff G. Posted January 31, 2006 Share Posted January 31, 2006 being slightly provocative, I wonder what the difference is between me deciding to reject all Email from a particular IP address and deciding not to accept Emails because they do not declare a sender address. If we argue that it is the right of the recipient to reject anything they prefer not to have passing through their server then do we not have a right to reject messages from null senders?39872[/snapback] According to the third-to-last paragraph of Listing policy for dsn.rfc-ignorant.org zone:If the rejection message clearly indicates the reason for denial as not being something related to the null-envelope (or above-mentioned timeout) ("{ip} rejected as listed on the MAPS RBL", etc.), then that spam-blocking shall not be considered grounds to list a domain.What you do with the message within your systems after you accept it is between you and your user population, but keep in mind the following quote of RFC2505 Anti-spam Recommendations for SMTP MTAs Section 2.6.1. (emphasis added): The MTA MUST NOT refuse to receive "MAIL From: <>". The "MAIL From: <>" address is used in error messages from the mail system itself, e.g. when a legitimate mail relay is used and forwards an error message back to the user. Refusing to receive [or dropping] such mail means that users may not be notified of errors in their outgong mail, e.g. "User unknown", which will no doubt wreak more havoc to the mail community than spam does. The most common case of such legitimate "MAIL From: <>" is to one recipient, i.e. an error message returned to one single individual. Since spammers have used "MAIL From: <>" to send to many recipients, it is tempting to either reject such mail completely or to reject all but the first recipient. However, there are legitimate causes for an error mail to go to multiple recipients, e.g. a list with several list owners, all located at the same remote site, and thus the MTA MUST NOT refuse "MAIL From: <>" even in this case. However, the MTA MAY throttle down the TCP connection ("read()" frequency) if there are more than one "RCPT To:" and that way slow down spammers using "MAIL From: <>". Link to comment Share on other sites More sharing options...
bradeck Posted February 1, 2006 Share Posted February 1, 2006 Hey y'all. I appreciate the information provided in this thread. From a business perspective, it makes complete sense to not let any potential customer slip through the cracks. That's why our autresponders were set up. I can understand how, though From address aliasing, my autoresponder could be considered spam. WOW. Nothing like inhibiting business. Anyway, I have gotten rid of them all now. I do have a request for the moderator. It was my autoresponse that was flagged as an example - anyway we can remove the company name so as not to drag it through the mud per se? Appreciate it. BTW - there are those whose sole business is software that blocks spam by predicating itself on the response of a valid user. Given your suggestions, these business would be completely illigit and rendered functionless. Am I wrong in that assessment? Link to comment Share on other sites More sharing options...
StevenUnderwood Posted February 1, 2006 Share Posted February 1, 2006 BTW - there are those whose sole business is software that blocks spam by predicating itself on the response of a valid user. Given your suggestions, these business would be completely illigit and rendered functionless. Am I wrong in that assessment? 39930[/snapback] Those are called Challenge/Response systems (C/R in many messages here) and they are considered abusive by many people. SpamCop used to employ this type of system until forged senders became such a problem. They are now reportable in spamcop as long as they were not generated due to a valid message (same as bounces are). Link to comment Share on other sites More sharing options...
agsteele Posted February 2, 2006 Share Posted February 2, 2006 BTW - there are those whose sole business is software that blocks spam by predicating itself on the response of a valid user. Given your suggestions, these business would be completely illigit and rendered functionless. Am I wrong in that assessment?39930[/snapback] You might like to see the FAQ item: Say NO to the Challenge/Response Lunacy Andrew Link to comment Share on other sites More sharing options...
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