Abstract: Content items are distributed to a content delivery network using identifiers that expresses relationships between the content items and at least one associated content element. When making requests to content delivery network, a requesting Web browser may thus specify the content items according to uniform resource locators that include credentials that allow the content delivery network to verify that the browser is authorized to receive the content items. These uniform resource locators may uniquely associate the content items with the associated content element and the requesting browser in a cryptographically secure manner.

Abstract: Methods and systems for facilitating limited access to paid-access or registration-required content items. In one example, a server responds to a request for access to a restricted access content item (e.g., from a Web browser) by first determining whether a user associated with the request is already authorized to access the content item. If the user is so authorized, the user is allowed access to the content item. If the user is not already authorized, the server provides the user a limited preview of the content item. The limited preview is subject to preview rules associated with one or more of: a referral path by which the user (i.e., the browser) was directed to the content item, the content item itself, and previous accesses or access attempts by the user to the content item and other content items, access to which other content items is controlled by the server.