I've seen some AWS documentation about how to mitigate DDoS attacks but this question is exclusively DoS. From the point of view of my EC2 instances, that are behind the ELB, the HTTP(S) requests are all being originated from the ELB, therefore the standard rules for firewall won't work to prevent multiple accesses from the same IP.
Considering DoS only, does AWS ELB already prevent/mitigate DoS attacks? If not, how are DoS attacks suppose to be handled when using AWS ELB?