Systematization of Knowledge: The Design Space of Digital Payment Systems with Potential for CBDC

Computer Science > Cryptography and Security [Submitted on 17 Mar 2026] Systematization of Knowledge: The Design Space of Digital Payment Systems with Potential for CBDC Judith Senn, Aljosha Judmayer, Nicholas Stifter, Rainer Böhme Central Bank Digital Currencies (CBDCs) are proposed as a public response to the uptake of privately run digital payments, with the digital euro, under development by the European Central Bank (ECB), serving as a prominent example. This momentum provides a unique opportunity to fundamentally rethink the future of money, and, assuming wide adoption, to establish payment systems that offer strong cryptographic security and privacy guarantees from the start. While the central banks in charge are investigating privacy-enhancing technologies (PETs), they often conclude that PETs are immature or insufficiently scalable. Moreover, these efforts tend to examine primitives in isolation, offering little insight into how a system using these PETs would scale. This systematisation of knowledge, therefore, provides a structured, top-down technical analysis of 36 payment system designs of complete system proposals that can inform CBDC designs or were explicitly proposed for this application. We identify recurring design patterns, technical trade-offs, and implementation challenges. Concluding, we highlight research gaps, including offline payments and post-quantum security. Comments: 38 pages, 3 figures, Subjects: Cryptography and Security (cs.CR) Cite as: arXiv:2603.16320 [cs.CR]   (or arXiv:2603.16320v1 [cs.CR] for this version)   https://doi.org/10.48550/arXiv.2603.16320 Focus to learn more Submission history From: Judith Senn [view email] [v1] Tue, 17 Mar 2026 09:53:22 UTC (92 KB) Access Paper: view license Current browse context: cs.CR < prev   |   next > new | recent | 2026-03 Change to browse by: cs References & Citations NASA ADS Google Scholar Semantic Scholar Export BibTeX Citation Bookmark Bibliographic Tools Bibliographic and Citation Tools Bibliographic Explorer Toggle Bibliographic Explorer (What is the Explorer?) Connected Papers Toggle Connected Papers (What is Connected Papers?) Litmaps Toggle Litmaps (What is Litmaps?) scite.ai Toggle scite Smart Citations (What are Smart Citations?) Code, Data, Media Demos Related Papers About arXivLabs Which authors of this paper are endorsers? | Disable MathJax (What is MathJax?)