Urn: The transport layer is the important layer

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. Unlike a URL, a URN doesn't provide any information about locating the resource but simply identifies it, just like a pure URI. In particular, a URN is a URI whose scheme is urn and has the following structure, as described by the RFC 2141: urn :: URN definition: 1. a container, especially a large, round one on a stem, that is used for decorative purposes in a…. Learn more. An Update Request Number or URN is an ID composed of 14 digits that applies uniquely every time a change/update request is made on an Aadhaar card. You can also consider it as a reference ID for your application.