Route53 also:
A) Serves DNS from multiple domain names. A number of variants in .com .org and others etc
B) Serves DNS from multiple internet networks / sources. Queries from an end user don't all hit the same Anycast subnet.
A) Serves DNS from multiple domain names. A number of variants in .com .org and others etc
B) Serves DNS from multiple internet networks / sources. Queries from an end user don't all hit the same Anycast subnet.
For DDoS attacks, I'm not sure what you mean by a "stated policy." They do a lot of countermeasures, some of which can be found via linked PDFs at https://aws.amazon.com/security/ Various R53 items are included in their DDoS document there. Officially you get charged. Unofficially, it depends on the circumstances. There's also a world of difference between a DDoS attack against a fully managed offering (like R53) versus, say, an EC2 instance.
Have you seen a better approach taken by other providers? I don't mean technical approach (which is near impossible to compare other than by track record), but from a policy perspective?