Document (#28697)

Author: Goodman, J.
Heckerman, D.
Rounthwaite, R.
Title: Schutzwälle gegen Spam
Source: Spektrum der Wissenschaft. 2005, H.7, S.92-100
Year: 2005
Series: E-Mails
Abstract: Täglich überfluten Milliarden lästiger Werbe-E-Mails - Spam - das Internet. sie belasten die weltweiter Kommunikation. Wie lässt sich dieses Ärgernis eindämmen?
Die erste Spam wurde 1978 an 400 Empfänger im Arpanet geschickt. Absender war ein Mitarbeiter der PR-Abtei lung von Digital Equipment Corporation (Dec), der darin für den damals neuen Decsystem-20-Rechner der Firma warb. Heute macht Spam mehr als zwei Drittel der über das Internet versandten E-Mails aus; täglich werden mehrere Milliarden solcher unverlangten Werbebotschaften versandt. Ein Drittel aller EMail-Nutzer hat mehr als 80 Prozent Spam in der elektronischen Post. Seit einiger Zeit sorgt Spam zudem durch so genannte Phishing-Attacken für Ärger: Dabei werden gefälschte E-Mails, die Fake-E-Mails, verschickt, die scheinbar von Mitarbeitern großer, Vertrauen erweckender Institutionen stammen, tatsächlich aber von Betrügern kommen - um damit Kreditkartennummern oder andere persönliche Informationen auszuspionieren. Nach einer Studie von Gartner Research von 2004 verursachen Phishing-Attacken in den USA Schäden in Höhe von jährlich 1,2 Milliarden Dollar. Spammer nutzen nicht nur E-Mail. In Chatrooms warten »Roboter«, die sich als Menschen ausgeben und Leute zu Klicks auf pornografische Webseiten verleiten sollen. Nutzer von Instant-Messaging-Systemen (IM) bekommen es mit so genannten splMs zu tun, engen »Verwandten« des Spams. In Web-Blogs (Web-Tagebüchern) lauern »Link-Spammer«, welche die Arbeit von Internetsuchmaschinen manipulieren, indem sie unerwünschte Links hinzufügen - was die Nutzung von Webseiten und Links erschwert. Spam steht teilweise in dem Ruf, die Internetkommunikation zu behindern oder gar zum Erliegen zu bringen. Die Wirklichkeit sieht indes nicht ganz so schwarz aus. Softwareentwickler haben verschiedene Techniken ersonnen, Spam auszufiltern und Spammern das Handwerk zu erschweren - weitere werden in Labors erprobt. Die hier vorgestellten Methoden richten sich gegen Junk-EMail, könnten aber auch zur Eindämmung anderer Spamvarianten verwendet werden. Keine dieser Techniken vermag Wunder zu vollbringen, doch ihre Kombination - sofern möglichst viele User sie anwenden - verspricht zumindest deutliche Verbesserungen. Es ist nicht unrealistisch zu hoffen, dass unsere E-MailPostfächer eines Tages wieder nahezu frei von Spam sein werden.
Footnote: Mit einer Grafik zum Prinzip des Spamming und der Spam-Abwehr
Theme: Internet
Object: E-Mail

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