Generating Temporary Download URLs
Sometimes you need to generate temporary links - URLs that expire after a certain timespan - so that a resource indicated by the link can be accessed only for a specific period. The URL if accessed after the stipulated time window refuses to serve the intended resource. Although there can be various approaches to generate such temporary URLs, this article demonstrates a flexible and easy way to do so using ASP.NET routing coupled with download token generation logic.
http://www.binaryintellect.net/articles/a22aaa2f-1c0a-41ba-98bf-faf3351e2f91.aspx