urn : URLs A Uniform Resource Name ( URN ) is a URI that identifies a resource by name in a particular namespace. URNs provide globally-unique names for resources as opposed to providing information about their location (URL). The transport layer is the important layer in the OSI reference model. A URN is a uniform resource identifier that provides a way of uniquely naming a resource without specifying an access protocol or mechanism, and without specifying a particular location. The URN number in Aadhaar, or Update Request Number, is a 14-digit code generated when an individual applies to update their Aadhaar card details. If you’re wondering what is URN , it serves as a tracking ID to monitor the Aadhaar update status online or offline. URN stands for Uniform Resource Name. It is a URI that uses a URN scheme. " urn " scheme: It is followed by a namespace identifier, followed by a colon, followed by namespace specific string. URN does not imply the availability of the identified resource.