DNS zone walking - Amazon Route 53
Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China (PDF).

DNS zone walking

A DNS zone walking attack attempts to get all content from DNSSEC-signed DNS zones. If Route 53 Resolver team detects a traffic pattern that matches the ones generated when DNS zones are walked on your endpoint, the service team will throttle the traffic on your endpoint. As a consequence you might observe a high percentage of your DNS queries timing out.

If you observe reduced capacity on your endpoints and believe that the endpoint have been throttled erroneously, go to https://console.amazonaws.cn/support/home#/ to create a support case.