DOI System Overview > Benefits of the DOI System > Solution to the Broken Link (Persistence)

The DOI System provides the means for a solution to the famous web issue of “http 404 not found” (broken link).

The problem is that a URL (Unified Resource Locator) is both an identifier and a locator for a resource on the Internet. The specific content of the URL that is its identifier is also the string that can be resolved into a location. This has the consequence that when a resource is moved from one service to another, from a server to another, or from a company to another, it will get a new URL that identifies the service, the server or the company that hosts it. Its old URL will most likely stop working and any previously made references to that resource using the old URL will no longer work.

With the DOI System, the identifier is persistent, whereas the metadata to which it resolves can change over time, in particular, the URL can be updated. For more information, see DOI Namespace.