A Survey and Analysis of the P3P Protocol's Agents, Adoption, Maintenance, and Future

In this paper, we survey the adoption of the platform for privacy preferences protocol (P3P) on Internet Web sites to determine if P3P is a growing or stagnant technology. We conducted a pilot survey in February 2005 and our full survey in November 2005. We compare the results from these two surveys and the previous (July 2003) survey of P3P adoption. In general, we find that P3P adoption is stagnant, and errors in P3P documents are a regular occurrence. In addition, very little maintenance of P3P policies is apparent. These observations call into question P3P's viability as an online privacy-enhancing technology. Our survey exceeds other previous surveys in our use of both detailed statistical analysis and scope; our February pilot survey analyzed more than 23,000 unique Web sites, and our full survey in November 2005 analyzed more than 100,000 unique Web sites.