2025-schweinfurt.tex (21012B)
1 \documentclass[aspectratio=169,t]{beamer} 2 \input taler-macros 3 4 \newcommand{\TITLE}{NEXT \\ GENERATION \\ INTERNET} 5 \newcommand{\SUB}{The GNU Taler Payment System} 6 \newcommand{\AUTHOR}{Christian Grothoff} 7 \newcommand{\SPEAKER}{Christian Grothoff} 8 \newcommand{\INST}{The GNU Project} 9 \newcommand{\DATE}{December 2025} 10 11 % Do not edit this part 12 \title{\TITLE} 13 \subtitle{\SUB} 14 \date{\DATE} 15 \author[\SPEAKER]{\AUTHOR} 16 \institute{\INST} 17 18 19 \usepackage{amsmath} 20 \usepackage{multimedia} 21 \usepackage[utf8]{inputenc} 22 \usepackage{framed,color,ragged2e} 23 \usepackage[absolute,overlay]{textpos} 24 \definecolor{shadecolor}{rgb}{0.8,0.8,0.8} 25 \usetheme{boxes} 26 \setbeamertemplate{navigation symbols}{} 27 \usepackage{xcolor} 28 \usepackage[normalem]{ulem} 29 \usepackage{listings} 30 \usepackage{adjustbox} 31 \usepackage{array} 32 \usepackage{bbding} 33 \usepackage{relsize} 34 \usepackage{graphicx} 35 \usepackage{tikz,eurosym,calc} 36 \usetikzlibrary{tikzmark} 37 \usetikzlibrary{shapes,arrows,arrows.meta} 38 \usetikzlibrary{positioning,fit,patterns} 39 \usetikzlibrary{calc} 40 \usepackage{multicol} 41 \usepackage{pgf-umlsd} 42 \usepackage{relsize} 43 44 \usepackage{booktabs} 45 \usepackage{makecell} 46 \usepackage{arydshln} 47 48 49 50 % "The GNU Taler Payment System", including 51 % an introduction to our objectives, 52 % background on the technology, 53 % demonstration of the system, 54 % social implications and open issues. 55 56 % CSS 57 \lstdefinelanguage{CSS}{ 58 basicstyle=\ttfamily\scriptsize, 59 keywords={color,background-image:,margin,padding,font,weight,display,position,top,left,right,bottom,list,style,border,size,white,space,min,width, transition:, transform:, transition-property, transition-duration, transition-timing-function}, 60 sensitive=true, 61 morecomment=[l]{//}, 62 morecomment=[s]{/*}{*/}, 63 morestring=[b]', 64 morestring=[b]", 65 alsoletter={:}, 66 alsodigit={-} 67 } 68 69 % JavaScript 70 \lstdefinelanguage{JavaScript}{ 71 basicstyle=\ttfamily\scriptsize, 72 morekeywords={typeof, new, true, false, catch, function, return, null, catch, switch, var, if, in, while, do, else, case, break}, 73 morecomment=[s]{/*}{*/}, 74 morecomment=[l]//, 75 morestring=[b]", 76 morestring=[b]' 77 } 78 79 \lstdefinelanguage{HTML5}{ 80 basicstyle=\ttfamily\scriptsize, 81 language=html, 82 sensitive=true, 83 alsoletter={<>=-}, 84 morecomment=[s]{<!-}{-->}, 85 tag=[s], 86 otherkeywords={ 87 % General 88 >, 89 % Standard tags 90 <!DOCTYPE, 91 </html, <html, <head, <title, </title, <style, </style, <link, </head, <meta, />, 92 % body 93 </body, <body, 94 % Divs 95 </div, <div, </div>, 96 % Paragraphs 97 </p, <p, </p>, 98 % scripts 99 </script, <script, 100 % More tags... 101 <canvas, /canvas>, <svg, <rect, <animateTransform, </rect>, </svg>, <video, <source, <iframe, </iframe>, </video>, <image, </image> 102 }, 103 ndkeywords={ 104 % General 105 =, 106 % HTML attributes 107 charset=, src=, id=, width=, height=, style=, type=, rel=, href=, 108 % SVG attributes 109 fill=, attributeName=, begin=, dur=, from=, to=, poster=, controls=, x=, y=, repeatCount=, xlink:href=, 110 % CSS properties 111 margin:, padding:, background-image:, border:, top:, left:, position:, width:, height:, 112 % CSS3 properties 113 transform:, -moz-transform:, -webkit-transform:, 114 animation:, -webkit-animation:, 115 transition:, transition-duration:, transition-property:, transition-timing-function:, 116 } 117 } 118 119 \lstdefinelanguage{JavaScript}{ 120 basicstyle=\ttfamily\scriptsize, 121 keywords={typeof, new, true, false, catch, function, return, null, catch, switch, var, if, in, while, do, else, case, break, for}, 122 keywordstyle=\color{blue}\bfseries, 123 ndkeywords={class, export, boolean, throw, implements, import, this}, 124 ndkeywordstyle=\color{darkgray}\bfseries, 125 identifierstyle=\color{black}, 126 sensitive=false, 127 comment=[l]{//}, 128 morecomment=[s]{/*}{*/}, 129 commentstyle=\color{purple}\ttfamily, 130 stringstyle=\color{red}\ttfamily, 131 morestring=[b]', 132 morestring=[b]" 133 } 134 135 \setbeamersize{description width=1em} 136 137 \definecolor{blue}{rgb}{0,0,0.7} 138 \newcommand{\orange}[1]{{\color{orange}#1}} 139 \newcommand{\blue}[1]{{\color{blue}#1}} 140 \newcommand{\red}[1]{{\color{red}#1}} 141 \newcommand{\Guardian}{\mathcal{G}} 142 \newcommand{\Child}{\mathcal{C}} 143 \newcommand{\Customer}{\mathcal{C}} 144 \newcommand{\Merchant}{\mathcal{M}} 145 \newcommand{\Exchange}{\mathcal{E}} 146 147 \newcommand{\Commit}{\mathsf{Commit}} 148 \newcommand{\Attest}{\mathsf{Attest}} 149 \newcommand{\Verify}{\mathsf{Verify}} 150 \newcommand{\Derive}{\mathsf{Derive}} 151 \newcommand{\DeriveCompare}{\mathsf{DeriveCompare_\kappa}} 152 \newcommand{\Compare}{\mathsf{Compare}} 153 \newcommand{\AgeVer}{\mathsf{AgeVer}} 154 155 \newcommand{\HashF}{\mathsf{H}} 156 \newcommand{\Hash}{\mathsf{H}} 157 \newcommand{\Block}{\mathbb{B}} 158 \newcommand{\Pub}{\mathsf{Pub}} 159 \newcommand{\Sign}{\mathsf{Sig}} 160 \newcommand{\Ver}{\mathsf{Ver}} 161 \newcommand{\Encoding}{\mathsf{Encoding}} 162 \newcommand{\ECDSA}{\mathsf{ECDSA}} 163 \newcommand{\Null}{\mathcal{O}} 164 \newcommand{\EC}{\mathrm{ec}} 165 \newcommand{\Curve}{\mathsf{Curve25519}} 166 \newcommand{\SHA}{\mathsf{SHA256}} 167 \newcommand{\SHAF}{\mathsf{SHA252}} 168 \newcommand{\FDH}{\mathsf{FDH}} 169 170 \newcommand{\negl}{\epsilon} 171 172 \newcommand{\rand}{\mathsf{rand}} 173 \newcommand{\age}{\mathsf{a}} 174 \newcommand{\Age}{\mathsf{M}} 175 \newcommand{\bage}{\mathsf{b}} 176 \newcommand{\minage}{\mathsf{m}} 177 \newcommand{\attest}{\mathsf{T}} 178 \newcommand{\commitment}{\mathsf{Q}} 179 \newcommand{\pruf}{\mathsf{P}} 180 \newcommand{\Vcommitment}{\vec{\mathsf{Q}}} 181 \newcommand{\Vpruf}{\vec{\mathsf{P}}} 182 \newcommand{\blinding}{\beta} 183 184 \newcommand{\ZN}{\mathbb{Z}_N} 185 \newcommand{\Z}{\mathbb{Z}} 186 \newcommand{\N}{\mathbb{N}} 187 \newcommand{\A}{\mathbb{A}} 188 \newcommand{\E}{\mathbb{E}} 189 \newcommand{\F}{\mathbb{F}} 190 \newcommand{\seck}{\mathsf{s}} 191 \newcommand{\pubk}{\mathsf{P}} 192 \renewcommand{\H}{\mathbb{H}} 193 \newcommand{\K}{\mathbb{K}} 194 \newcommand{\Proofs}{\mathbb{P}} 195 \newcommand{\Commitments}{\mathbb{O}} 196 \newcommand{\Attests}{\mathbb{T}} 197 \newcommand{\Blindings}{\mathbb{B}} 198 \newcommand{\Nil}{\perp} 199 200 \newcommand{\p}{\mathsf{p}} 201 \newcommand{\com}{\mathsf{com}} 202 \newcommand{\prf}{\mathsf{prf}} 203 204 \newcommand{\Adv}{\mathcal{A}} 205 \newcommand{\PPT}{\mathfrak{A}} 206 \newcommand{\Probability}{\mathrm{Pr}} 207 \newcommand{\Algorithm}{f} 208 \renewcommand{\Game}[1]{G_\Adv^\mathsf{#1}} 209 210 \DeclareMathOperator{\Image}{Im} 211 \DeclareMathOperator{\Mod}{mod} 212 213 \newcommand{\Encode}[1]{\overbracket[0.5pt][2pt]{\,#1\,}} 214 \newcommand{\Decode}[1]{\underbracket[0.5pt][3pt]{\,#1\,}} 215 \newcommand{\FDHg}[1]{[#1]_g\,} 216 \newcommand{\logg}{{\breve{g}}} 217 218 219 \newcommand{\drawfrom}{\xleftarrow{\$}} 220 \newcommand\Exists{% 221 \mathop{\lower0.75ex\hbox{\ensuremath{% 222 \mathlarger{\mathlarger{\mathlarger{\mathlarger{\exists}}}}}}}% 223 \limits} 224 225 \newcommand\Forall{% 226 \mathop{\lower0.75ex\hbox{\ensuremath{% 227 \mathlarger{\mathlarger{\mathlarger{\mathlarger{\forall}}}}}}}% 228 \limits} 229 230 231 \begin{document} 232 233 \begin{frame}[plain] 234 \maketitle 235 \end{frame} 236 237 \begin{frame}{Agenda} 238 \tableofcontents 239 \end{frame} 240 241 \section{Motivation \& Background} 242 243 244 \begin{frame}{A Social Problem} 245 % \vfill 246 This was a question posed to RAND researchers in 1971: 247 248 \begin{quote} 249 ``Suppose you were an advisor to the head of the KGB. Suppose you are given the assignment of designing a system for the surveillance of all citizens and visitors within the boundaries of the USSR. The system is not to be too obtrusive or obvious. What would be your decision?'' 250 \end{quote} 251 %The result: an electronic funds transfer system that looks 252 %strikingly similar today's debit card system. 253 \pause 254 \begin{minipage}{2cm} 255 \includegraphics[width=2cm]{pics/nsa_spy.jpg} 256 \end{minipage} 257 \begin{minipage}{12cm} 258 ``I think one of the big things that we need to do, is we need 259 to get away from true-name payments on the Internet. The credit 260 card payment system is one of the worst things that happened for the 261 user, in terms of being able to divorce their access from their 262 identity.'' \hfill --Edward Snowden, IETF 93 (2015) 263 \end{minipage} 264 265 \end{frame} 266 267 268 \begin{frame}{Banks have Problems, too!} 269 270 3D secure (``verified by visa'') is a nightmare: 271 272 \begin{minipage}{5cm} 273 \begin{itemize} 274 \item Complicated process 275 \item Shifts liability to consumer 276 \item Significant latency 277 \item Can refuse valid requests 278 \item Legal vendors excluded 279 \item No privacy for buyers 280 \end{itemize} 281 \end{minipage} 282 \begin{minipage}{5cm} 283 \includegraphics[width=\textwidth]{illustrations/cc3ds.pdf} 284 \end{minipage} 285 \vfill 286 Online credit card payments will be replaced, but with what? 287 \end{frame} 288 289 290 \begin{frame}{The Bank's Problem} 291 \begin{itemize} 292 \item Global tech companies push oligopolies 293 \item Privacy and federated finance are at risk 294 % \item 30\% fees are conceivable 295 \item Economic sovereignty is in danger 296 \end{itemize} 297 \begin{textblock*}{4cm}(11.5cm,5.2cm) % {block width} (coords) 298 {\includegraphics[width=\textwidth]{../investors/competitor-logos/amazon.png}} 299 \end{textblock*} 300 \begin{textblock*}{2cm}(11cm,3cm) % {block width} (coords) 301 {\includegraphics[width=\textwidth]{../investors/competitor-logos/alipay.jpeg}} 302 \end{textblock*} 303 \begin{textblock*}{2cm}(11cm,7cm) % {block width} (coords) 304 {\includegraphics[width=\textwidth]{../investors/competitor-logos/paypal.jpeg}} 305 \end{textblock*} 306 \begin{textblock*}{2cm}(3cm,9cm) % {block width} (coords) 307 {\includegraphics[width=\textwidth]{../investors/competitor-logos/applepay.jpeg}} 308 \end{textblock*} 309 \begin{textblock*}{2cm}(7cm,7cm) % {block width} (coords) 310 {\includegraphics[width=\textwidth]{../investors/competitor-logos/samsungpay.jpeg}} 311 \end{textblock*} 312 \begin{textblock*}{1cm}(9.5cm,6.3cm) % {block width} (coords) 313 {\includegraphics[width=\textwidth]{../investors/competitor-logos/android_pay.png}} 314 \end{textblock*} 315 \vfill 316 \end{frame} 317 318 319 \begin{frame}{Predicting the Future} 320 \begin{itemize} 321 \item Google and Apple will be your bank and run your payment system 322 \item They can target advertising based on your purchase history, location and 323 your ability to pay 324 \item They will provide more usable, faster and broadly available 325 payment solutions; our federated banking system will be history 326 % just like SMTP is now Gmail. 327 \item After they dominate the payment sector, they will start to charge fees 328 befitting their oligopoly size 329 \item Competitors and vendors not aligning with their corporate ``values'' 330 will be excluded by policy and go bankrupt 331 \item The imperium will have another major tool for its financial warfare 332 \end{itemize} 333 \end{frame} 334 335 336 \begin{frame}{Central Bank Digital Currency?} 337 Speech by Augustin Carstens, Bank of International Settlements (October 2020) on the difference between Central Bank Digital Currencies and cash. 338 \begin{center} 339 \movie[height = 0.5\paperheight, poster, showcontrols]{Central Bank Digital Currency vs. Cash} 340 {bis-cbdc.mp4} 341 342 {\tiny 343 \url{https://www.youtube.com/watch?v=R_E4Uu7ycqE} (10'2020)} 344 \end{center} 345 \end{frame} 346 347 348 349 \section{GNU Taler: Introduction} 350 351 \begin{frame} 352 \vfill 353 \begin{center} 354 {\bf GNU Taler: Introduction} 355 \end{center} 356 \vfill 357 \end{frame} 358 359 360 \begin{frame}{GNU Taler~\cite{taler2016space,DBLP:phd/hal/Dold19,cbdc2021chaum}} 361 \vfill 362 \begin{center} 363 {\huge {\bf Digital} cash, made \textbf{socially responsible}.} 364 \end{center} 365 \vfill 366 \begin{center} 367 \includegraphics[scale=0.3]{taler-logo-2021-inkscape.pdf} 368 \end{center} 369 \vfill 370 \begin{center} 371 Privacy-Preserving, Practical, Taxable, Free Software, Efficient 372 \end{center} 373 \vfill 374 \vfill 375 \ % 376 \end{frame} 377 378 379 \begin{frame}{What is Taler?} 380 \framesubtitle{\url{https://taler.net/en/features.html}} \noindent 381 Taler is 382 \vfill 383 \begin{itemize} 384 \item a Free/Libre software \emph{payment system} infrastructure project 385 \item ... with a surrounding software ecosystem 386 \item ... and a company (Taler Systems S.A.) and community that wants to deploy it 387 as widely as possible. 388 \end{itemize} 389 \vfill 390 \noindent 391 However, Taler is 392 \begin{itemize} 393 \item \emph{not} a currency or speculative asset 394 \item \emph{not} a long-term store of value 395 \item \emph{not} a network or instance of a system 396 \item \emph{not} based on proof-of-work or proof-of-stake 397 \end{itemize} 398 \end{frame} 399 400 401 \begin{frame}{Design principles} 402 \framesubtitle{https://taler.net/en/principles.html} 403 GNU Taler must ... 404 \begin{enumerate} 405 \item {... be implemented as {\bf free software}.} 406 \item {... protect the {\bf privacy of buyers}.} 407 \item {... enable the state to {\bf tax income} and crack down on 408 illegal business activities.} 409 \item {... prevent payment fraud.} 410 \item {... only {\bf disclose the minimal amount of information 411 necessary}.} 412 \item {... be usable.} 413 \item {... be efficient.} 414 \item {... avoid single points of failure.} 415 \item {... foster {\bf competition}.} 416 \end{enumerate} 417 \end{frame} 418 419 420 \begin{frame} 421 \frametitle{Taler Overview} 422 \begin{center} 423 \begin{tikzpicture} 424 \tikzstyle{def} = [node distance= 5em and 6.5em, inner sep=1em, outer sep=.3em]; 425 \node (origin) at (0,0) {}; 426 \node (exchange) [def,above=of origin,draw]{Exchange}; 427 \node (customer) [def, draw, below left=of origin] {Customer}; 428 \node (merchant) [def, draw, below right=of origin] {Merchant}; 429 \node (auditor) [def, draw, above right=of origin]{Auditor}; 430 % \node (regulator) [def, draw, above=of auditor]{CSSF}; 431 432 \tikzstyle{C} = [color=black, line width=1pt] 433 434 \draw [<-, C] (customer) -- (exchange) node [midway, above, sloped] (TextNode) {withdraw coins}; 435 \draw [<-, C] (exchange) -- (merchant) node [midway, above, sloped] (TextNode) {deposit coins}; 436 \draw [<-, C] (merchant) -- (customer) node [midway, above, sloped] (TextNode) {spend coins}; 437 \draw [<-, C] (exchange) -- (auditor) node [midway, above, sloped] (TextNode) {verify}; 438 % \draw [<-, C] (regulator) -- (auditor) node [midway, above, sloped] (TextNode) {report}; 439 440 \end{tikzpicture} 441 \end{center} 442 \end{frame} 443 444 445 446 \begin{frame} 447 \frametitle{Architecture of Taler} 448 \begin{center} 449 \includegraphics[width=0.8\textwidth]{operations.png} 450 \end{center} 451 \end{frame} 452 453 454 \begin{frame}{Consumer Impact of Taler} 455 \begin{itemize} 456 \item {\bf Convenient:} pay with one click instantly --– in Euro, 457 Dollar, Yen or Bitcoin 458 \item {\bf Friction-free security:} Payments do not require sign-up, 459 login or multi-factor authentication 460 \item {\bf Privacy-preserving:} payment requires/shares no personal information 461 \item {\bf Bank account:} not required 462 \end{itemize} 463 \end{frame} 464 465 466 \begin{frame}{Merchant Impact of Taler} 467 \begin{itemize} 468 \item {\bf Instant clearance:} one-click transactions and instant clearance at par 469 \item {\bf Easy \& compliant:} GDPR \& PCI-DSS compliance-free and without any effort 470 \item {\bf Major profit increase:} efficient protocol $+$ no fraud $=$ extremely low costs 471 \item {\bf 1-click checkout:} without Amazon and without false positives in fraud detection 472 \end{itemize} 473 \end{frame} 474 475 476 \begin{frame}{Usability of Taler} 477 \vfill 478 \begin{center} 479 \url{https://demo.taler.net/} 480 \end{center} 481 \begin{enumerate} 482 \item Install browser extension. 483 \item Visit the {\tt bank.demo.taler.net} to withdraw coins. 484 \item Visit the {\tt shop.demo.taler.net} to spend coins. 485 \end{enumerate} 486 \vfill 487 \end{frame} 488 489 490 \input protocol-basics.tex 491 \input offline.tex 492 \input oim.tex 493 494 495 \begin{frame}{The Emergency Act of Canada} 496 Speech by Premier Kenney, Alberta, February 2022. 497 \begin{center} 498 \movie[height = 0.5\paperheight, poster, showcontrols]{The Emergency Act of Canada} 499 {emergencyact.mp4} 500 501 {\tiny \url{https://www.youtube.com/watch?v=NehMAj492SA} (2'2022)} 502 \end{center} 503 \end{frame} 504 505 506 507 508 \section{Future Work \& Conclusion} 509 510 \begin{frame} 511 \vfill 512 \begin{center} 513 {\bf Future Work \& Conclusion} 514 \end{center} 515 \vfill 516 \end{frame} 517 518 519 \begin{frame}{Use Case: Journalism} 520 Today: 521 \begin{itemize} 522 \item Corporate structure % ($\Rightarrow$ filter) 523 \item Advertising primary revenue % ($\Rightarrow$ dependence) 524 \item Tracking readers critical for business success 525 \item Journalism and marketing hard to distinguish 526 \end{itemize}\vfill\pause 527 With GNU Taler: 528 \begin{itemize} 529 \item One-click micropayments per article 530 \item Hosting requires no expertise % (no PCI DSS) 531 \item Reader-funded reporting separated from marketing 532 \item Readers can remain anonymous 533 \end{itemize} 534 \end{frame} 535 536 537 \begin{frame}{Taler: Project Status} 538 \framesubtitle{\url{https://docs.taler.net/}} 539 \begin{itemize} 540 \item Cryptographic protocols and core exchange component are stable 541 \item Pilot project at Bern University of Applied Sciences cafeteria 542 \item Netzbon (regional currency) in Basel launched 543 \item Taler Operations AG live Swiss-wide 544 \item Internal alpha deployment with GLS Bank (Germany) 545 \item Internal alpha deployment with Magnet Bank (Hungary) 546 \end{itemize} 547 \end{frame} 548 549 550 \begin{frame}{Competitor comparison} 551 \begin{center} \small 552 \begin{tabular}{l||c|c|c|c|c} 553 & Cash & Bitcoin & Zerocoin & Creditcard & GNU Taler \\ \hline \hline 554 Online &$-$$-$$-$ & ++ & ++ & + & +++ \\ \hline 555 Offline & +++ & $-$$-$ & $-$$-$ & + & $+$$+$ \\ \hline 556 Trans. cost & + & $-$$-$$-$ & $-$$-$$-$ & $-$ & ++ \\ \hline 557 Speed & + & $-$$-$$-$ & $-$$-$$-$ & o & ++ \\ \hline 558 Taxation & $-$ & $-$$-$ & $-$$-$$-$ & +++ & +++ \\ \hline 559 Payer-anon & ++ & o & ++ & $-$$-$$-$ & +++ \\ \hline 560 Payee-anon & ++ & o & ++ & $-$$-$$-$ & $-$$-$$-$ \\ \hline 561 Security & $-$ & o & o & $-$$-$ & ++ \\ \hline 562 Conversion & +++ & $-$$-$$-$ & $-$$-$$-$ & +++ & +++ \\ \hline 563 Libre & $-$ & +++ & +++ & $-$ $-$ $-$& +++ \\ 564 \end{tabular} 565 \end{center} 566 \end{frame} 567 568 569 \begin{frame}{Other ongoing developments} 570 \begin{itemize} 571 \item Privacy-preserving auctions (trading, currency exchange) ({\tt oezguer@taler.net}) 572 \item Hardware and software support for embedded systems ({\tt mikolai@taler.net}) 573 \item Tax-deductable receipts for donations to charities (donau.git) 574 \item Unlinkable anonymous subscriptions and discount tokens ({\tt ivan@taler.net}) 575 \item $\ldots$ 576 \end{itemize} 577 \end{frame} 578 579 580 \begin{frame}{Open Challanges} 581 \begin{itemize} 582 \item Try to explain this to lawyers and AML staff of banks 583 \item What are convincing arguments for citizens to switch? 584 \item How to address anti-competitive cash-back from card payments? 585 \item $\ldots$ 586 \end{itemize} 587 \end{frame} 588 589 590 \begin{frame}{How to support?} 591 \begin{description} 592 \item[Join:] {\small \url{https://lists.gnu.org/mailman/listinfo/taler}} 593 \item[Discuss:] {\small \url{https://ich.taler.net/}} 594 \item[Develop:] \url{https://bugs.taler.net/}, \url{https://git.taler.net/} 595 \item[Apply:] \url{https://nlnet.nl/propose}, \url{https://nlnet.nl/taler} 596 \item[Translate:] \url{https://weblate.taler.net/}, \url{translation-volunteer@taler.net} 597 \item[Integrate:] \url{https://docs.taler.net/} 598 \item[Donate:] \url{https://gnunet.org/ev} 599 \item[Partner:] \url{https://taler-systems.com/} 600 \end{description} 601 \end{frame} 602 603 604 \begin{frame}{Conclusion} 605 \begin{center} 606 {\bf What can we do?} 607 \end{center} 608 \vfill 609 \begin{itemize} 610 \item{Suffer mass-surveillance enabled by credit card oligopolies with high fees, and} 611 \item{Engage in arms race with deliberately unregulatable blockchains} 612 % \item{Enjoy the ``benefits'' of cash \\ 613 % \hfill \includegraphics[height=0.3\textheight]{atm-rupee.jpg} \hfill} 614 \end{itemize} 615 \vfill 616 \begin{center} 617 {\bf OR} 618 \end{center} 619 \vfill 620 \begin{itemize} 621 \item{Establish free software alternative balancing social goals!} 622 \end{itemize} 623 \vfill 624 \end{frame} 625 626 627 628 \section*{References} 629 \begin{frame}[allowframebreaks]{References} 630 \bibliographystyle{plain} 631 \bibliography{ref,extra,rfc,biblio-defqa} 632 \end{frame} 633 634 635 % This should be last... 636 \begin{frame}{Acknowledgments} 637 638 \begin{minipage}{0.45\textwidth} \ \\ 639 {\tiny Funded by the European Union (Project 101135475).} 640 641 \begin{center} 642 \includegraphics[width=0.5\textwidth]{../bandera.jpg} 643 \end{center} 644 \end{minipage} 645 \hfill 646 \begin{minipage}{0.45\textwidth} 647 {\tiny Funded by SERI (HEU-Projekt 101135475-TALER).} 648 649 \begin{center} 650 \includegraphics[width=0.65\textwidth]{../sbfi.jpg} 651 \end{center} 652 \end{minipage} 653 654 \vfill 655 656 {\tiny 657 658 Views and opinions expressed are however those of the author(s) only 659 and do not necessarily reflect those of the European Union. Neither the 660 European Union nor the granting authority can be held responsible for 661 them. 662 663 } 664 \end{frame} 665 666 667 \end{document} 668 669 670 671 \begin{frame}{Future work} 672 \begin{itemize} 673 \item Performance improvements for RSA in FLOSS crypto libraries 674 \item Integrate with e-ID for easier \& cheaper KYC 675 \item Buy anonymous pre-paid debit cards on-demand with Taler wallet 676 \item Implement PQC across the stack (with cipher agility, where possible with additive security) 677 \end{itemize} 678 \end{frame}