Google proposes ‘Privacy Sandbox’ for linking relevant ads and privacy

Under the name Privacy Sandbox, Google proposes a number of open web standards that, according to the company, links personalization of advertisements to privacy for the user. Blocking cookies without an alternative threatens the privacy and future of the web, according to Google.

Google calls the Privacy Sandbox a “secure personalization environment that also protects user privacy.” In fact, it involves a series of proposals as part of the Chromium project, such as APIs to measure adclick conversion, a privacy budget against fingerprinting, and a trust token API.

Google refers, among other things, to its plans with Federated Learning. This enables a browser to display relevant advertisements without revealing data that can be traced back to an individual. The browser does this by making the user part of a large group in terms of data, while anonymity is preserved.

With API calls, websites can get enough information to designate a user as a member of such a group, but the browser then blocks further calls. The company calls this a ‘privacy budget’. Blocking cookies is, according to Google, a deadly way because developers would circumvent this, including fingerprinting, which would be at the expense of privacy. The user would be worse off because they can delete cookies. Google wants to prevent fingerprinting through the privacy budget. According to Google, blocking cookies with no other method for relevant ads will reduce publishers’ revenue, jeopardizing the future of the “lively” web.

Google is also working on techniques that allow advertisers to measure conversion without having to track a user. In addition, the company is testing methods to prevent fraud with ad clicks, in which privacy techniques can also play a role. Google refers to CloudFlares PrivacyPass token, which internet users can use to make their identity anonymous on multiple sites, without tracking.