333 lines
4.6 KiB
HTML
333 lines
4.6 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
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<HTML
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><HEAD
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><TITLE
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>Techniques</TITLE
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><META
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NAME="GENERATOR"
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CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK
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REL="HOME"
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TITLE="Spam Filtering for Mail Exchangers"
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HREF="index.html"><LINK
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REL="PREVIOUS"
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TITLE="The SMTP Transaction"
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HREF="smtpintro.html"><LINK
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REL="NEXT"
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TITLE="SMTP Transaction Delays"
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HREF="smtpdelays.html"></HEAD
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><BODY
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CLASS="chapter"
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BGCOLOR="#FFFFFF"
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TEXT="#000000"
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LINK="#0000FF"
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VLINK="#840084"
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ALINK="#0000FF"
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><DIV
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CLASS="NAVHEADER"
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><TABLE
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SUMMARY="Header navigation table"
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WIDTH="100%"
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BORDER="0"
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CELLPADDING="0"
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CELLSPACING="0"
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><TR
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><TH
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COLSPAN="3"
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ALIGN="center"
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>Spam Filtering for Mail Exchangers: </TH
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></TR
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><TR
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><TD
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WIDTH="10%"
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ALIGN="left"
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VALIGN="bottom"
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><A
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HREF="smtpintro.html"
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ACCESSKEY="P"
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>Prev</A
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></TD
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><TD
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WIDTH="80%"
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ALIGN="center"
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VALIGN="bottom"
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></TD
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><TD
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WIDTH="10%"
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ALIGN="right"
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VALIGN="bottom"
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><A
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HREF="smtpdelays.html"
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ACCESSKEY="N"
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>Next</A
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></TD
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></TR
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></TABLE
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><HR
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ALIGN="LEFT"
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WIDTH="100%"></DIV
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><DIV
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CLASS="chapter"
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><H1
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><A
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NAME="techniques"
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></A
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>Chapter 2. Techniques</H1
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><DIV
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CLASS="TOC"
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><DL
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><DT
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><B
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>Table of Contents</B
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></DT
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><DT
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>2.1. <A
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HREF="smtpdelays.html"
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>SMTP Transaction Delays</A
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></DT
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><DT
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>2.2. <A
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HREF="dnschecks.html"
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>DNS Checks</A
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></DT
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><DD
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><DL
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><DT
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>2.2.1. <A
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HREF="dnschecks.html#dnsbl"
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>DNS Blacklists</A
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></DT
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><DT
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>2.2.2. <A
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HREF="dnschecks.html#rdns"
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>DNS Integrity Check</A
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></DT
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></DL
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></DD
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><DT
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>2.3. <A
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HREF="smtpchecks.html"
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>SMTP checks</A
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></DT
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><DD
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><DL
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><DT
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>2.3.1. <A
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HREF="smtpchecks.html#helocheck"
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>Hello (HELO/EHLO) checks</A
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></DT
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><DT
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>2.3.2. <A
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HREF="smtpchecks.html#senderchecks"
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>Sender Address Checks</A
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></DT
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><DT
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>2.3.3. <A
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HREF="smtpchecks.html#rcptchecks"
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>Recipient Address Checks</A
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></DT
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></DL
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></DD
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><DT
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>2.4. <A
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HREF="greylisting.html"
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>Greylisting</A
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></DT
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><DD
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><DL
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><DT
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>2.4.1. <A
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HREF="greylisting.html#greylisting-theory"
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>How it works</A
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></DT
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><DT
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>2.4.2. <A
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HREF="greylisting.html#greylisting-multimx"
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>Greylisting in Multiple Mail Exchangers</A
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></DT
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><DT
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>2.4.3. <A
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HREF="greylisting.html#greylisting-results"
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>Results</A
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></DT
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></DL
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></DD
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><DT
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>2.5. <A
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HREF="senderauth.html"
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>Sender Authorization Schemes</A
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></DT
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><DD
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><DL
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><DT
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>2.5.1. <A
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HREF="senderauth.html#spf"
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>Sender Policy Framework (SPF)</A
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></DT
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><DT
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>2.5.2. <A
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HREF="senderauth.html#ms-cide"
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>Microsoft Caller-ID for E-Mail</A
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></DT
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><DT
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>2.5.3. <A
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HREF="senderauth.html#rmxplus"
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>RMX++</A
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></DT
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></DL
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></DD
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><DT
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>2.6. <A
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HREF="datachecks.html"
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>Message data checks</A
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></DT
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><DD
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><DL
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><DT
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>2.6.1. <A
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HREF="datachecks.html#headerchecks"
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>Header checks</A
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></DT
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><DT
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>2.6.2. <A
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HREF="datachecks.html#jmsr"
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>Junk Mail Signature Repositories</A
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></DT
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><DT
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>2.6.3. <A
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HREF="datachecks.html#garbagechars"
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>Binary garbage checks</A
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></DT
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><DT
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>2.6.4. <A
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HREF="datachecks.html#mimeerrors"
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>MIME checks</A
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></DT
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><DT
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>2.6.5. <A
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HREF="datachecks.html#fileext"
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>File Attachment Check</A
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></DT
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><DT
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>2.6.6. <A
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HREF="datachecks.html#virusscanners"
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>Virus Scanners</A
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></DT
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><DT
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>2.6.7. <A
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HREF="datachecks.html#spamscanners"
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>Spam Scanners</A
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></DT
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></DL
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></DD
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><DT
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>2.7. <A
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HREF="collateral.html"
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>Blocking Collateral Spam</A
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></DT
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><DD
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><DL
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><DT
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>2.7.1. <A
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HREF="collateral.html#bogusviruswarning"
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>Bogus Virus Warning Filter</A
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></DT
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><DT
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>2.7.2. <A
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HREF="collateral.html#addspf"
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>Publish SPF info for your domain</A
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></DT
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><DT
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>2.7.3. <A
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HREF="collateral.html#signedsender"
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>Enveloper Sender Signature</A
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></DT
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><DT
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>2.7.4. <A
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HREF="collateral.html#dsnrealuser"
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>Accept Bounces Only for Real Users</A
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></DT
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></DL
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></DD
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></DL
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></DIV
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><BLOCKQUOTE
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CLASS="ABSTRACT"
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><DIV
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CLASS="abstract"
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><A
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NAME="AEN579"
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></A
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><P
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></P
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><P
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> In this chapter, we look at various ways to weed out junk mail
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during the SMTP transaction from remote hosts. We will also try
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to anticipate some of the side effects from deploying these
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techniques.
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</P
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><P
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></P
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></DIV
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></BLOCKQUOTE
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></DIV
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><DIV
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CLASS="NAVFOOTER"
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><HR
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ALIGN="LEFT"
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WIDTH="100%"><TABLE
|
|
SUMMARY="Footer navigation table"
|
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WIDTH="100%"
|
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BORDER="0"
|
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CELLPADDING="0"
|
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CELLSPACING="0"
|
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><TR
|
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><TD
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WIDTH="33%"
|
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ALIGN="left"
|
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VALIGN="top"
|
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><A
|
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HREF="smtpintro.html"
|
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ACCESSKEY="P"
|
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>Prev</A
|
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></TD
|
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><TD
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WIDTH="34%"
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ALIGN="center"
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VALIGN="top"
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><A
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HREF="index.html"
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ACCESSKEY="H"
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>Home</A
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></TD
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><TD
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WIDTH="33%"
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ALIGN="right"
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VALIGN="top"
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><A
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HREF="smtpdelays.html"
|
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ACCESSKEY="N"
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>Next</A
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></TD
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></TR
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><TR
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><TD
|
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WIDTH="33%"
|
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ALIGN="left"
|
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VALIGN="top"
|
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>The SMTP Transaction</TD
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><TD
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WIDTH="34%"
|
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ALIGN="center"
|
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VALIGN="top"
|
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> </TD
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><TD
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WIDTH="33%"
|
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ALIGN="right"
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VALIGN="top"
|
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>SMTP Transaction Delays</TD
|
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></TR
|
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></TABLE
|
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></DIV
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></BODY
|
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></HTML
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> |