The name server checks its database and cache, doesn't find anything, and sends an iterative request to a root server for the .com top-level domain.

该名称服务器检查其数据库和缓存，没有找到任何结果，于是向 .com 顶级域的根服务器发送一个迭代请求。

youdao

Domain name root server refers to the server that bear the function of root nodes in the domain name system.

域名根服务器：是指承担域名体系中根节点功能的服务器。

youdao

Specifically, ICANN is responsible for coordinating the assignment of protocol parameters, overseeing the domain name system, allocating IP-address space and managing the root-server system.

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