Wondering about how PDF’s phone home

Submitted by Danny Weitzner on Thu, 2006-07-13 21:40. ::
Wondering about how PDF’s phone home

The original appearance of this entry was in Danny Weitzner - Open Internet Policy

Recently noticed this description of the Adobe Policy Server:

About Adobe LiveCycle Policy Server. Authors who protect their documents with Adobe LiveCycle Policy Server can audit what is done with each copy of the document (such as opening, printing, and editing). They can also change or revoke access rights at any time. If an author has revoked access to a document that is protected by Adobe LiveCycle Policy Server, Adobe Reader or Acrobat informs you that your access rights have been removed the next time you try to open the document.

I wonder how this works.