Jonas, thanks for the reply. Some queries below, if you have the time.
Mike On 6/14/07, Jonas Eckerman <[EMAIL PROTECTED]> wrote:
Blocking because a system/netblock has made many attempts to send to non-existant users makes sense. Any single address from wich a certain number of such attempts is done during a the last n minutes are blocked with a tenporary failure here. Netzero might well be doing something similar.
Granted, but it seems to me that it is very much easier to detect these violations at the destination that at the source. The implication is that we must keep count of every failed recipient for every sender on our domain and maintain a rolling average. Unless there is some tool or some feature of my current tools that I am unaware, I am not sure that this is feasible. Perhaps there is some industry accepted means of doing this offline? Whatever the technology, if these ISPs are genuinely interested in blocking spam, wouldn't it make sense for them to provide some more detailed information on who the offender was (email address) so that we would have a starting point. Many other sites provide us with this evidence and we quickly investigate and either block the sender or correct their behavior. Of course it is also possible that they block in a way that
doesn't make sense. Without knowing what your system(s)/netblock did to their system(s), what made them block you, and how long the temporary period is, it's impossible to judge wether it makes any sense or not. Regards /Jonas -- Jonas Eckerman, FSDB & Fruktträdet http://whatever.frukt.org/ http://www.fsdb.org/ http://www.frukt.org/
