A Web page cache that stores Web pages such that servers will be able to
retrieve valid dynamic pages without going to a dynamic content server or
origin Web server for the page every time a user requests that dynamic
page. The dynamic content cache receives information that defines data
upon which each dynamic page is dependent, such that when the value of
any dependency data item changes, the associated dynamic page is marked
as invalid or deleted. The dynamic page cache stores dependency data,
receives change event information, and indicates when pages in the cache
are invalidated or need to be refreshed.