My best guess from a receivers perspective is: If >99.9% of the traffic from a netblock were spam (let’s say from half of the IPs in that block), I don’t want to accept any more messages from the other IPs from the same netblock (and risk unhappy recipients and - even worse - financial impact because they contact support) because statistically they are most likely spam too.
Even though some of the other IPs might be clean.. the positive impact of rejecting the whole netblock is most likely no more spam, even from IPs I never received a single mail from before (meaning happier users, no support costs,…) vs. the negative impact of very few false positives which cost almost nothing. I don’t say that this is necessarily good the way it is, but I can totally understand the idea behind that. > Am 14.10.2019 um 15:58 schrieb Nick via mailop <[email protected]>: > > On 2019-10-14 14:41 BST, Graeme Fowler via mailop wrote: >> On 14 Oct 2019, at 14:30, Nick via mailop <[email protected]> wrote: >>> If an ip address in the range is held by a legitimate mailer, you're >>> saying the legitimate mailer will be evicted to make way for the >>> spammer? Does that really happen? >> >> No; but if you don't get any email from the 'legitimate' sender then >> your only signal is that from the neighbours. > > Sure, and blocking the neighbours who are deemed spammers is not what > I'm questioning. > >> If a large percentage of them have a signal which is 'poor' (FSVO >> 'poor') then the inference is that the whole block is poisonous, and >> you bin it (or put mail from it in the junk folder). > > It is not an inference. You agreed ("Does that really happen?" "No") > that legitimate senders remain in the block. The whole block is not > poisonous. > > My question remains unanswered. Why not treat each ip address on its > own merits? Is it technically infeasible, too expensive, less > convenient, or what? > -- > Nick > > _______________________________________________ > mailop mailing list > [email protected] > https://chilli.nosignal.org/cgi-bin/mailman/listinfo/mailop _______________________________________________ mailop mailing list [email protected] https://chilli.nosignal.org/cgi-bin/mailman/listinfo/mailop
