2024-09.html.j2 (6261B)
1 {% extends "common/news.j2" %} 2 {% block body_content %} 3 <h1>Privacy-preserving Subscriptions, Discounts and Tax Deductable Donations</h1> 4 5 <p> 6 Two independent bachelor theses bring new privacy-focused features to GNU Taler. 7 Christian Blättler designed and implemented token-based subscriptions and discounts in Taler, while Lukas Matyja 8 and Johannes Casaburi's thesis introduces the Donau system, a new type of a donation authority system. 9 </P> 10 11 <h2>Privacy-preserving Subscriptions and Discounts</h2> 12 13 <p> 14 Christian Blättler finished his <a href="/papers/subscription-discounts-thesis.pdf">bachelor thesis</a> about 15 designing and implementing token-based subscriptions and discounts in Taler. 16 </p> 17 18 <h3>Introduction video</h3> 19 <p> 20 <video id="video" poster="/videos/subscription-discounts-movie.jpg" autobuffer="" height="360" width="640" 21 controls="controls"> 22 <source src="/videos/subscription-discounts-movie.mp4" type="video/mp4" \> 23 </video> 24 </p> 25 26 <h3>Abstract</h3> 27 <p> 28 Subscription-based services are more popular than ever, with a significant portion of digital goods, such as newspaper 29 articles, music, movies, and TV shows, sold through this business model. These services are generally tied to a user 30 account. As a result, the use of a subscription leaves a data trail. Service providers can use collected usage data to 31 build a personality profile that can reveal information about political views, sexual orientation, health 32 complications, or other sensitive topics. 33 </p> 34 <p> 35 This information, in the wrong hands, can have critical implications, especially in regions with repressive regimes. 36 Ideally, a solution to this problem also addresses the challenge of subscribers sharing their credentials with groups 37 of people online. 38 </p> 39 <p> 40 This thesis presents a solution for account-less and privacy-preserving subscriptions based on GNU Taler. The solution 41 is convenient for customers, affordable for merchants, and resistant to abusive sharing of subscriptions. 42 Subscriptions are valid during a configured timeframe, while usage during that timeframe is unlimited. The flexible 43 design of the solution allows it to be used for a wide array of use cases beyond subscriptions, such as discounts, 44 loyalty stamps, multi-entry event ticketing, membership programs, deposit systems, and privacy-preserving gifts. In 45 addition, the solution's low operational costs, coupled with its built-in protection against abusive sharing of 46 subscriptions, make it highly attractive to merchants. 47 </p> 48 <p> 49 The solution is implemented in the <a href="https://git-www.taler.net/merchant.git/" target="_blank">GNU Taler merchant 50 component</a> as free and open source software. The integration into the GNU Taler wallets is subject to future 51 work. Furthermore, to inform customers about the degree of anonymity for a given subscription, an additional service 52 for authorizing the anonymity set size of subscriptions is proposed. 53 </p> 54 55 <h3>Supplemental material</h3> 56 <p> 57 <ul> 58 <li><a href="/pdf/subscription-discounts-book-entry.pdf" target="_blank">One pager</a></li> 59 <li><a href="/pdf/subscription-discounts-poster.pdf" target="_blank">Defense poster</a></li> 60 <li><a href="/papers/subscription-discounts-thesis.pdf" target="_blank">Bachelor's thesis</a></li> 61 <li><a href="/pdf/subscription-discounts-slides.pdf" target="_blank">Defense presentation slides</a></li> 62 </ul> 63 </p> 64 65 <hr> 66 67 <h2>Donau - Tax Deductable Donations with Privacy</h2> 68 <p> 69 Johannes Casaburi and Lukas Matyja finished their <a 70 href="/papers/donau-thesis.pdf" target="_blank">Bachelor's thesis</a></li> on 71 the design and implementation of a privacy-preserving donation system with 72 integrated receipts for tax-deduction. 73 </p> 74 <h3>Introduction video</h3> 75 <p> 76 <video id="video" poster="/videos/donau-thumbnail.png" autobuffer="" height="360" width="640" 77 controls="controls"> 78 <source src="/videos/donau-video.mp4" type="video/mp4" \> 79 </video> 80 </p> 81 <h3>Abstract</h3> 82 <p> 83 This project describes the design of a privacy-preserving donation 84 system. The central entity in the design is the donation authority 85 (Donau) which was implemented in free software in the context of the 86 GNU Taler project. While implemented primarily for GNU Taler, the 87 system could in principle work with other payment systems. 88 </p> 89 <p> 90 Providing evidence of charitable donations for tax deductions often requires 91 sensitive personal information, raising privacy concerns. 92 Donors may wish to anonymize receipts while still being able to make 93 legitimate donations to recognized charities. On the other side tax authorities 94 may wish to better prevent donation fraud with verifiable signatures. 95 Deductions for unrecognized charities or failure to deduct valid foreign 96 donations also occur. A system allowing anonymous yet verifiable donation 97 receipts would address these issues. The Donau would be operated by a tax 98 authority. The Donau backend 99 implements a REST API used primarily by charities and donors. It 100 maintains a list of recognized charities, enabling tax authorities to 101 audit the total amount of donation receipts each charity is 102 issuing. Upon making a donation to one of the charities the donor 103 receives a <i>donation receipt</i> which will be stored locally on 104 the donor’s device. Throughout this process neither the charity nor 105 the Donau obtains any identifiable information about the donor, 106 thus enabling anonymous donations. To simplify the verification for 107 the tax authority, the donor needs to submit their donation receipts 108 to the Donau at the end of the year. At that time, the Donau can 109 combine the individual donation receipts in one final annual 110 <i>donation statement</i>. Upon request of the tax authority, the 111 donor can provide this donation statement to the tax authority which 112 can check its validity and can then approve the tax deduction. 113 </p> 114 115 <h3>Supplemental material</h3> 116 <p> 117 <ul> 118 <li><a href="https://docs.taler.net/core/api-donau.html">Donau API</a></li> 119 <li><a href="/pdf/donau-booklet.pdf" target="_blank">One pager</a></li> 120 <li><a href="/pdf/donau-poster.pdf" target="_blank">Donau poster</a></li> 121 <li><a href="/papers/donau-thesis.pdf" target="_blank">Bachelor's thesis</a></li> 122 </ul> 123 </p> 124 {% endblock body_content %}