换言之，当你产生一个新标识符时，你就产生了一个全新的东西，不论它是一个HTTP头、媒体类型标识还是一个URI。

In other words, every time you mint a new identifier, you're minting a fundamentally new thing, whether it be a HTTP header, a format identified by a media type, or a URI.

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URN的替代方法是仅将DNS系统作为多媒体类型标识符的一部分。

An alternative to going all the way to URNs might be to make use of the DNS system alone as part of a media type identifier.

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统一资源标识符(Uniform Resource Identifiers, URI)为标识Web中的资源定义了一种标准系统，这些资源包括html页面、XML文档、图像、多媒体文件等等。

Uniform resource Identifiers (URIs) define a standard system for identifying resources on the Web, including HTML pages, XML documents, images, multimedia files, and more.

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