CAPTCHA Wide Review Draft Published

Today the Accessible Platform Architectures (APA) Working Group, with the assistance of its Research Questions Task Force (RQTF), has published another draft update to the W3C Note "Inaccessibility of CAPTCHA", first published in 2005:

http://www.w3.org/TR/turingtest

We thank the community for comments provided on earlier drafts of this document. Your comments have helped us improve our analysis of the state of the art in telling human users apart from their robotic impersonators.

While there are editorial revisions in almost every paragraph of this latest draft, some of the highlights include:

• A new section on Proof of Work;
• A significant rewrite of the section on reCAPTCHA;
• Two new sections on Turing Tokens and Federated Turing Tokens to discuss recent non-interactive blinded verification approaches which we've named "Turing Tokens."

To be sure the updated document is as complete as possible, we once again solicit public input on this version. The following questions will help guide your review:

• Does this document fully capture current problems with CAPTCHA and related systems?
• Are there other CAPTCHA approaches that should be added?
• Are there concerns for certain categories of persons with disabilities that remain unaddressed or insufficiently addressed in this document?
• Are you aware of relevant research or technological development in this area we missed?
• Have we sufficiently addressed CAPTCHA's problems with internationalization, privacy, and security?
• Is "Turing Tokens" a reasonable name for the blinded verification tokens described in section 3.4? And, is our new visionary section 3.5 based on Turing Tokens clear? Or, should it be its own, separate document?
• Have we mis-characterized anything we discuss?

Please submit any comments by 26 July 2019. To comment, open a new issue in the W3C APA GitHub repository. If this is not feasible, send email to public-apa@w3.org (comment archive). In-progress updates to the document are publicly visible in the editors' draft.

Janina Sajka, Chair Accessible Platform Architectures (APA) Working Group