I know that this question may sound like an invalid serverfault question, but I believe that it's quite valid: the amount of time and effort that a sysadmin should spend on DDoS protection is a direct function of typical DDoS prices. Let me rephrase this: protecting a web site against small attacks is one thing, but resisting 50 Gbps of UDP flood is another and requires time & money. Deciding whether or not to spend that time & money depends on whether such an attack is likely or not, and this in turn depends on how cheap and simple such an attack is for the attacker.
So here's the full story: our company has been victim to a massive DDoS attack (over 50 Gbps of UDP traffic, full-time during 2 weeks). We are pretty sure that it's one of our competitors, and we actually know which one, because we were the only two remaining competitors on a very big request for proposal, and the DDoS attack magically stopped the day we won (double hurray, by the way)!
These people have proved in the past that they are very dishonest, but we know that they are not technical at all, so we believe that they simply paid for some botnet DDoS service. I would like to know how much these services typically cost, for such a large scale attack. Please do not give any link to such services, I would really hate to give these people any publicity.
I understand that a hacker could very well do this for free, but what's a typical price for such an attack if our competitors paid for it through some kind of botnet service? It is really starting to scare me (if we're talking thousands of dollars here, then I am really going to freak off: who knows, they might just hire a hit-man one day?).
Of course we filed a complaint, but the police says that they cannot do much about it (DDoS attacks are virtually untraceable, so they say), and our suspicions are not enough to justify them raiding our competitor's offices to search for proofs.
For your information, we now changed our infrastructure to be able to sustain such attacks: we now use a major CDN service so that our servers are not directly affected by DDoS attacks. Requests for dynamic pages do get proxied to our servers, but for low level attacks (UDP flood, or Syn floods, for example) we only receive legitimate trafic, so we're fine. If they decide to launch higher level attacks (HTTP flood or slowloris attacks for example), most of the load should be handled by the CDN... at least I hope so!
Thank you very much for your help.