i-number
i-numbers are a type of Internet identifier designed to solve the problem of how any web resource can have a persistent identity that never changes even when the web resource moves or changes its human-friendly name. For example, if a web page has an i-number, and links to that page use the i-number, then those links will not break even if the page is renamed, the website containing the page is complete reorganized, or the page is moved to another website.