I don't know much about security, but here's what I think I understand about my question, at a high level:
- DDoS attacks are caused by a LOT of network traffic, which can be hard to mitigate because you can't anticipate where they're coming from.
- One method of two-factor authentication is to set up a trusted connection to a synchronized system that dynamically generates a security token.
- During a recent DDoS attack on my favorite MMO, one of my friends made a comment about "the only thing they can do is change ports and hope the attackers don't pick up the change for a while".
So, one question is: is it an accurate assumption that it would be hard to keep up a DDoS attack if the provider kept changing the ports that it expects data to come into? This seems reasonable to me.
And the second question is: if so, are there any drawbacks to using some kind of synchronized system to change the ports every so often, to make it harder for the DDoS attack to persist? So, if you have a trusted client, you would have "your current port" to talk to, and when it's time to change, your client would know to make the change.
Like I said, I don't know enough to know all the (I'm sure) massive flaws in my question, but this doesn't seem like something that would have a crazy performance hit, and it seems like a good way to keep attackers out of your system.