Demo: AuthPaper - protecting paper-based documents/credentials using authenticated 2D barcodes

All printed documents and credentials are potentially subject to counterfeiting and forgery. Conventional counterfeiting solutions such as watermarking or printing with special-quality paper are not cost-effective. Certification via authorized chops/ stamps is low-cost but only provides a false sense of security/ authenticity. While embedding a serial number in the document for online verification is low-cost and secure, it is not applicable without Internet connection. We demonstrate AuthPaper (Authenticated Paper) to solve these problems by: 1) Digitally sign on the document to be protected; 2) Put the original content, digital signature and optionally the signer's certificate in a self-describing encapsulation; 3) Generate a 2D barcode (e.g. QR code) to carry the encapsulation and embed it as an integral part of the paper document. Note that the information carried in Authenticated QR Code is 40 to 50 times more than a typical one (≈50 Bytes). The biggest technical challenge is to scan and decode such densely packed codes in a robust manner. We have developed an Android application to address the challenge. In short, AuthPaper provides a secure, low-cost and offline method for document authentication.