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DDoS and Open Resolvers: The Swiss view

About a month ago the openresolver project  published the results of a global scan enumerating open recursive DNS Servers. A daunting 27.200.613 systems where found.

In the past we’ve reported on large scale DDoS attacks in this blog. The attacks are real, and they are not just some rare random occurrences on the net. The recent attack on Spamhaus illustrates this quite clearly. People have different views on Spamhaus’ activities, but that’s not the point. The point is that there are people out there that can launch massive attacks that even Tier 1 carriers will feel. And it’s not only “Spammers against Spamhouse” that do this. A recent attack we analysed, weighting “only a few dozens MBits/s” was launched by a literal looser, someone who did not get what he wanted in an MMOG, against a game server. We also see attacks against competitors, to black mail people and, quite ironically in the name of “internet freedom of speech”, against disagreeable sites.

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