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Re: Providers removing blocks on port 135?
On Sat, 20 Sep 2003 23:22:34 +0100 "Ray Bellis" <email@example.com> wrote: > What we do have though are (optional) *inbound* filters that make sure > no-one can connect to their privileged ports over TCP/IP, and a mandatory > filter that says only our network can deliver to their SMTP service. > > We don't get problems with open-relays on dialups. We didn't have any > problems with MS-Blaster on dialups either... I would suggest instead that you have mandatory sending via your relays, and allow inbound connections to port 25. Sympatico, last I checked, didn't have any restrictions until you tripped off their alarms, at which point you needed to configure your smtpd to send mail via their relays. If they continued spewing copious amounts of spam, cut them off entirely until they fix their configuration. There are a couple of pluses to this type of setup; people like me who have dozens of (required) email addresses can forward them all to their home machine. Some of my family also much prefer this even though they've only got one or two email addresses. It also ensures that they can't send spam directly no matter what the source; blocking inbound connections will certainly stop open relays, but it won't stop trojans and worms and whatnot that are really just spamware. (Note that I consider spamware included in other applications and hidden from the user "trojans.")