How do I detect a DoS/DDoS attack directed at me?
An unusually large amount of traffic, servers suddenly experiencing above average loads, all these can be signs of a DoS/DDoS attack, on the other hand it might represent a high usage peak. In any event you should examine the traffic and usage patterns, if the traffic is legitimate then you will probably want to tune your network and servers, or add additional equipment, if the traffic is an attack then you will need to deal with it accordingly. There are a number of Network Intrusion Detection Systems (NIDS) which can detect hostile attacks with a pretty good degree of accuracy, they may are a good investment if installed and maintained properly.
