How to block DDoS?

[ultan]

If one day some one attacked your network with a DDoS how would you block it or would the way to do this is wait out and hope he gives up?

[cornelis]

Maybe you can try limiting the amount of request per IP.
But well... if some professional hitman attacks I think it will be from numerous different IPs and hitting on you all at one time.

Never knew what could be done, because some big coporations have been taken down before and what could small ones do?

[augustine]

I read that what most smaller companies do it to wait for the fire to burn out by itself.
But that will cause some amounts of downtime, unless your online operation is not important then its not advisable.

[ultan]

Wait out and hope for the best? Yeeks... that does not seem like a good suggestion.
Anyone know what the big companies do?