What is the difference between P3P and OPS?
While P3P and OPS are somewhat similar, the focus and originating requirement of each technology is different. P3P was initially focussed on enabling the expression of privacy practices and preferences. OPS’s focus was on the secure storage, transport, and control of user data. It has been clear to the developers of P3P from the beginning that “data exchange” is relevant to P3P. (If a site asks you for a piece of information, they might as well tell you what their practice is.) When OPS was submitted to P3P, P3P members decided to examine OPS and determine how to integrate P3P with data exchange. To put it simply, P3P originally allowed a service and user to reach an explicit understanding about the site’s data privacy practices. OPS allows users to control the release of their data in a secure manner. Today, all the data-transfer protocol is removed from P3P, see also question I.
