DNS简单说是域名翻译系统。它本身也是一个网络。DNS缺省,和网络速度没有关系。网络速度和你的ISP(网络服务提供商),本地网络和传输是否处于繁忙时间段等因素有关系。关于DNS的解释,请看下面的英文说明:
Short for Domain Name System (or Service or Server), an Internet service that translates domain names into IP addresses. Because domain names are alphabetic, they're easier to remember. The Internet however, is really based on IP addresses. Every time you use a domain name, therefore, a DNS service must translate the name into the corresponding IP address. For example, the domain name
www.example.com might translate to 198.105.232.4.
The DNS system is, in fact, its own network. If one DNS server doesn't know how to translate a particular domain name, it asks another one, and so on, until the correct IP address is returned.
参考资料:http://www.webopedia.com/TERM/D/DNS.html