For a long time now it's been a tough slog for anti-spam software companies, whose offerings never seem to have the impact they should.
Some low-technology workaround is developed that soon enough licks whatever protective shield vendors try to put in place – and spam continues unimpeded until the next "dream" product is announced and the cycle starts all over again.
The struggle between various species of spamsters and those who would seek to contain them continues full throttle. But indications are the crooks seem to be winning hands down.
They've developed counter-maneuvers for every major spam-blocking strategy, even those that for a while appeared to be containing the menace.
For instance, one stratagy that appeared to be getting good results - for a while at least - involved three levels of filtering.
Let's call it the "triple filter" approach.
Triple filter anti-spam tools work by "asking" three questions (who, what and which) of every e-mail coming in. Who is the sender? What are the contents? Which sites does the message link to?
That worked for a while, until the "bad guys" developed a three-pronged response.
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“道高一尺 魔高一丈” 能让垃圾邮件继续猖狂吗
有人说，垃圾邮件就是瘟疫，确实如此。近年来，随着垃圾邮件泛滥问题的日趋严重,许多反垃圾邮件的软件开发商也争先恐后陆陆续续地推出了一系列的打击垃圾邮件的软件。但「道高一尺，魔高一丈」，垃圾邮件的形式也更加变换多样，以避开那些反垃圾邮件软件的检测，从而继续逍遥于互联网上。
软件开发商每推出一项功能强大的反垃圾邮件的软件，那些潜伏着的垃圾邮件的制造者已经加紧脚步开始“推陈出新”以应对那些他们所谓的对手。
可以说，早在上个世纪第一封垃圾邮件被公布于世到现在，垃圾邮件和发垃圾邮件的这场这场战争就一直没有停息，相反却愈演愈烈。
怎样中止这场没有硝烟的战争，从根源上解决这一问题，还互联网一个清洁的环境，成了许多国家亟待解决的问题，同时这也是许多反垃圾邮件的开发商目前正在商讨的问题。
令人欣喜的是，一些开发商正在逐步推出一款款功能更加强大的软件。比如，目前他们推出了一项“三重过滤”系统，能够很好的反击垃圾邮件。可是好景不长，垃圾邮件又以另一种新形的形式在网上“畅游”，而这一形式恰恰是来应对“三重过滤”的。
这场战争到什么时候才能停息，让我们拭目以待。同时也希望这些垃圾邮件发送者能够在这场战争中自言残败。