Dilwyn Jones wrote: ... > There is an issue in particular with NTL which is causing havoc. > The root cause is spam, and many ISPs inept efforts at pre-filtering. > > I remember chaos at Demon a few years ago, when someone decided to put > them on a blacklist because one of their customers had an open relay. > > My ISP does absolutely nothing other than spend £100,00 plus to cope > with the spam traffic. That is fine by me - I would rather be in > control of my own filters.
Consider that the £100,00[0]+ has to come from somewhere: it'll end up coming from you in terms of costing you more to access their system - spam defence must form part of the cost you have to pay your ISP for using their systems and their providing you with email facilities. > One of my contacts using freeserve,co,uk is having terrible trouble. > Approximately 50% of her emails get filtered out somewhere in transit. That is curious. My old email address[1] was with freeserve (.fsnet.co.uk) and all the spam arrived having been through their filters, usually marked as "***SPAM***" in the subject field plus a couple of extra X- header fields. I believe there was/is a facility for the user to allow them to delete the spam at the ISP end (before even being seen); also I believe you could train their filters so that false positives, and negatives, could be corrected. [1] I stopped checking that old eaddr at the beginning of the year. When I last checked it a couple of days ago (telnet'ed in) it held 1001 messages (7,650,581 bytes) with the last message dated Tue 17 around 9:15am which leads me to suspect that it's now full (and probably bouncing all mail sent to it). > How do these ISP spam filterings work? > > Do they pattern match emails (i.e. look at it, that's spam, add it to > the list and stop every copy of that email) or simply decide that a > particular isp seems to carry a lot of c*** and focus on those alone? The freeserve/wanadoo mailings (I receive) include a score which must be based on content - I've had messages from the same (expected, non-spam) source some marked as spam, others not. For example, the header of the parent of this reply contains: ... X-DH-Virus-Scanned: by amavisd-new-20030616-p10 (Debian) at deathwish X-Spam-Status: No, hits=0.0 tagged_above=-999.0 required=999.0 tests= X-Spam-Level: ... X-me-spamlevel: not-spam X-me-spamrating: 0.398634 > I really do seem to get a lot less spam on tesco.net now, but what I > don't know of course is how many inncoent emails are being blocked. > Plus, as I'm on dial up, I tend to put a specific size "do not > download" on if I'm receiving emails at peak (costly) time. You could always download the headers of all messages without downloading the bodies. (The pop3 TOP command sends the message header along with the first n (specified) lines of the message - if specified as 0, only the header is sent.) _______________________________________________ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
