Akadēmiskais centrs
Lipmā ir pazīstams kā:
Trešdien, 27. aprīlī, 16:30, 13. auditorijā:
"On cryptographic protocols for Norwegian internet voting"
- plašam klausītāju lokam (sākot ar 1. kursa studentiem, kriptogrāfijas priekšzināšanas nav nepieciešamas).
Pēc lekcijas aptuveni 18:00 varētu būt studentu organizēta brīvā diskusija ar Lipmā.
Ceturtdien, 28. aprīlī, 15:00, 13. auditorijā:
"Progression-Free Sets and Sublinear Pairing-Based Non-Interactive Zero-Knowledge Arguments"
- klausītājiem ar priekšzināšanām kriptogrāfijā (vēlamais priekšzināšanu līmenis - bakalaura programmas kursa "Datu aizsardzība un kriptogrāfija" līmenī)
Gaidīti visi interesenti! -----------------------------------Anotācija trešdienas lekcijai---------------------------------------------------------
Helger Lipmaa: On cryptographic protocols for Norwegian internet voting
Abstract: Estonia is already implementing Internet voting in the national scale. In Norway, the plan is to have pilot elections in 2011 and full-scale elections in 2017. Differently from Estonia, Norwegian elections are supposed to be verifiable. Moreover, they should remain verifiable even in the presence of untrusted voter PCs. In 2009, we proposed a setting ("code-verification") for Norwegian Internet voting, that was also adopted in Norway. In this talk, I will explain the setting and two different code-verification voting protocols. The first protocol was originally proposed in 2009. Norway is going to use another protocol, which is more efficient but less secure. The second protocol we explain is as efficient as the official Norwegian protocol but achieves better security.
-----------------------------------Anotācija ceturtdienas lekcijai------------------------------------------------------
Helger Lipmaa: Progression-Free Sets and Sublinear Pairing-Based Non-Interactive Zero-Knowledge Arguments
Abstract: In Asiacrypt 2010, Groth constructed a non-interactive zero-knowledge (NIZK) argument for circuit satisfiability with constant communication, linear verifier's computation, and quadratic common reference string length and prover's computation. In the current paper, we show how to reduce the common reference string length to quasilinear, and the prover's computation from quadratic number of exponentiations to quadratic number of multiplications. We do this by using a connection to the theory of progression-free sets. As an independent technical construction, we show that for any $n > 0$, $[n]$ has a progression-free subset of odd integers of cardinality $n^{1 - o (1)}$. Moreover, we use slightly weaker security assumptions than Groth. One of the applications of the current paper is a perfect zap for circuit satisfiability with quasi square-root communication complexity.
- Igaunijas un Norvēģijas elektronisko vēlēšanu sistēmu izstrādātājs;
- starptautiskās kriptogrāfu asociācijas (International Association of Cryptography Research - šīs nozares galvenā profesionālā organizācija pasaulē) padomes loceklis;
- viens no 3 visvairāk citētajiem datoriķiem Baltijas valstīs;
Trešdien, 27. aprīlī, 16:30, 13. auditorijā:
"On cryptographic protocols for Norwegian internet voting"
- plašam klausītāju lokam (sākot ar 1. kursa studentiem, kriptogrāfijas priekšzināšanas nav nepieciešamas).
Pēc lekcijas aptuveni 18:00 varētu būt studentu organizēta brīvā diskusija ar Lipmā.
Ceturtdien, 28. aprīlī, 15:00, 13. auditorijā:
"Progression-Free Sets and Sublinear Pairing-Based Non-Interactive Zero-Knowledge Arguments"
- klausītājiem ar priekšzināšanām kriptogrāfijā (vēlamais priekšzināšanu līmenis - bakalaura programmas kursa "Datu aizsardzība un kriptogrāfija" līmenī)
Gaidīti visi interesenti! -----------------------------------Anotācija trešdienas lekcijai---------------------------------------------------------
Helger Lipmaa: On cryptographic protocols for Norwegian internet voting
Abstract: Estonia is already implementing Internet voting in the national scale. In Norway, the plan is to have pilot elections in 2011 and full-scale elections in 2017. Differently from Estonia, Norwegian elections are supposed to be verifiable. Moreover, they should remain verifiable even in the presence of untrusted voter PCs. In 2009, we proposed a setting ("code-verification") for Norwegian Internet voting, that was also adopted in Norway. In this talk, I will explain the setting and two different code-verification voting protocols. The first protocol was originally proposed in 2009. Norway is going to use another protocol, which is more efficient but less secure. The second protocol we explain is as efficient as the official Norwegian protocol but achieves better security.
-----------------------------------Anotācija ceturtdienas lekcijai------------------------------------------------------
Helger Lipmaa: Progression-Free Sets and Sublinear Pairing-Based Non-Interactive Zero-Knowledge Arguments
Abstract: In Asiacrypt 2010, Groth constructed a non-interactive zero-knowledge (NIZK) argument for circuit satisfiability with constant communication, linear verifier's computation, and quadratic common reference string length and prover's computation. In the current paper, we show how to reduce the common reference string length to quasilinear, and the prover's computation from quadratic number of exponentiations to quadratic number of multiplications. We do this by using a connection to the theory of progression-free sets. As an independent technical construction, we show that for any $n > 0$, $[n]$ has a progression-free subset of odd integers of cardinality $n^{1 - o (1)}$. Moreover, we use slightly weaker security assumptions than Groth. One of the applications of the current paper is a perfect zap for circuit satisfiability with quasi square-root communication complexity.