ViperDNS closed down (opens in new tab)

Presumably they have to change servers so often because that's how quickly Netflix detects them.

It's extremely unlikely Netflix will publish how they perform the detection, because that would make it easier for people to get around. My guess is that they know where your account should be located based on payment information or previous detection of region-switching services, and they use these flagged accounts to uncover new region switchers.

I would guess they have to get 'clean' IPs too. Simply moving the IP to a different server likely is not sufficient. Netflix also filters the common ASes, so you need to shuffle between exotic/new blocks

Even the TTL on a.dns.whatever is set to 1min, a lot of clients ignore the TTL and use the cached value for minutes to days after TTL expiration.

I agree, DNS as a service is still a relevant business model when targeting other use cases. But I disagree with the use of term 'pirate' here.

It's not even VPN, it's a DNS service that masks your location, similar to unlocator.com