German tech publication Heise.de has been targeted by a persistent and determined denial of service attack, it says. The origin of the attack is unknown so far, and Heise's publishing house is offering a €10,000 reward for information leading to the arrest of the attacker.

The assault began on Monday this week, and Heise reports that it has come in four waves. At its worst, it disabled the site for five hours. The first attack swamped the load-balancer, which manages the flow of traffic across the site's web servers. Heise's publishing house runs 25 web servers and one solaris machine, more than enough to handle an unexpected influx of visitors to the site.

As Heise's technical staff worked to deal with the influx of rubbish, the attacker changed his approach, probably by bringing more machines from different locations to bear. This would make it harder for Heise to filter out the noise, and put the site under renewed pressure. So far, the techies have ruled out an attack via HTTP requests, and say there is no truth in rumours that the Sober.K worm is responsible for its troubles.

The attacks have dropped off for the time being, and Heise is taking steps to protect itself against any new DDoS attempts, it says. ®

Heise's own story is here

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