ONVIF学习理解(3)

URI

1）          关于URI的一个误解。

A common misunderstanding of URIs is that they are only used to referto accessible resources.  The URI itself only provides identification; access to the resource is neither guaranteed nor implied by the presence of a URI.  Instead, any operation associated with a URI reference is defined by the protocol element, data format attribute, or natural language text in which it appears.

2）          格式

Percent-encoding. 使用%来转义（converse parsing）保留字段。

URI分为URL和URN。一个典型的URN的例子（ISBN 0-486-27557-4，urn:isbn:0-486-27557-4）。

A URL is a URI that, in addition to identifying aweb resource, specifies the means of acting upon or obtaining the representation。

A uniform resource name (URN) is a URI that identifies a resource by name, in a particular namespace。URI does not suggest where or how to obtain an actual copy of it。

3）      Syntax

The URI syntax consists of aURI scheme name (such as "http", "ftp", "mailto", "crid" or "file") followed by a colon character, and then by a scheme-specific part.

Example: <scheme name> : <hierarchical part> [ ? <query> ] [ # <fragment> ]