From owner-freebsd-chat Fri Sep 24 19: 8:30 1999 Delivered-To: freebsd-chat@freebsd.org Received: from lariat.lariat.org (lariat.lariat.org [206.100.185.2]) by hub.freebsd.org (Postfix) with ESMTP id 8F74715211 for ; Fri, 24 Sep 1999 19:08:28 -0700 (PDT) (envelope-from brett@lariat.org) Received: from mustang (IDENT:ppp0.lariat.org@lariat.lariat.org [206.100.185.2]) by lariat.lariat.org (8.9.3/8.9.3) with ESMTP id UAA06215; Fri, 24 Sep 1999 20:08:13 -0600 (MDT) Message-Id: <4.2.0.58.19990924200154.047b51a0@localhost> X-Sender: brett@localhost X-Mailer: QUALCOMM Windows Eudora Pro Version 4.2.0.58 Date: Fri, 24 Sep 1999 20:08:11 -0600 To: Jacques Vidrine , "Rodney W. Grimes" From: Brett Glass Subject: Re: Filtering port 25 (was Re: On hub.freebsd.org refusing to talk to dialups) Cc: chat@FreeBSD.ORG In-Reply-To: <19990925003530.6331CBE08@gw.nectar.com> References: <199909241637.JAA02838@gndrsh.dnsmgr.net> <199909241637.JAA02838@gndrsh.dnsmgr.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-freebsd-chat@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org At 07:35 PM 9/24/99 -0500, Jacques Vidrine wrote: >I am not advocating making it easy for spammers. The RBL has been a >huge help, and the DUL looks potentially even more helpful. I just >object to blocking legitimate traffic. The problem is, how can you tell what is legitimate? There's no good way, a priori, to distinguish spam from legitimate e-mail. It's only the pattern of mailing and/or the content that gives it away. Moreover, in order to detect an abusive pattern of mailing, you need to have logging -- which you get when you channel users' mail through your server. By doing so, you are not "blocking" mail. In fact, you're providing an additional service by queueing it for delivery -- possibly after the user has logged off. This is handy if the recipient's DNS or mail server is offline when the mail is first sent. See http://www.mercurycenter.com/svtech/news/indepth/docs/mc092399.htm for a good story about a small ISP and a spammer. --Brett To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-chat" in the body of the message