Menjava sporočil med dvema nezaupljivima strankama
magistrsko delo
Abstract
Namen magistrske naloge je konstruirati in implementirati protokol, ki omogoča dvema nezaupljiva strankama pošteno izmenjavo zasebnih rešitev problemov iz razreda NP brez posredovanja zaupanja vredne tretje osebe. Protokol omogoča preverjanje ustreznosti rešitev problemov iz razreda NP brez razkritja znanja in zagotavlja poštenost menjave, tj. če ena stranka predčasno odstopi od protokola, potem morata obe stranki vložiti primerljivo enako časa za pridobitev zaprošenih rešitev. Verifikacija sporočil temelji na protokolu "popačeno vezje", postopna poštena izmenjava le-teh pa na časovnih zaprisegah. Omejili smo se na izmenjavo rešitev problema iskanja praslik kriptografskih zgoščevalnih funkcij. Pri predpostavki da imamo dovolj dobro mrežno povezavo med sodelujočima, lahko s tako implementacijo izmenjamo krajša sporočila.
Keywords
večstrankarsko računanje;varna evalvacija funkcij;protokol popačeno vezje;dokaz brez razkritja znanja;sheme za zapriseganje;kriptografija javnih ključev;zgoščevalne funkcije;
Data
| Language: | Slovenian |
|---|---|
| Year of publishing: | 2019 |
| Typology: | 2.09 - Master's Thesis |
| Organization: | UL FRI - Faculty of Computer and Information Science |
| Publisher: | [K. Klanjšček] |
| UDC: | 004.42 |
| COBISS: |
18722905
|
| Views: | 1648 |
| Downloads: | 356 |
| Average score: | 0 (0 votes) |
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Other data
| Secondary language: | English |
|---|---|
| Secondary title: | Exchange of messages between two mistrusting parties |
| Secondary abstract: | In this thesis we discuss the construction and our implementation of a protocol that allows two independent parties a fair exchange of private solutions of NP problems without a trusted third party. The protocol allows verification of solutions of a NP problem using zero knowledge and ensures fairness of exchange, i.e., if one party quits the protocol early, then the two parties must invest comparable amounts of time to retrieve requested solutions. Verification of solutions is based on the garbled circuit protocol and the fair exchange is formed on timed commitments. Our focus was on exchange of messages with respect to the preimage problem of cryptographic hash functions. Assuming that we have enough bandwidth available we are able to exchange shorter messages. |
| Secondary keywords: | multiparty computation;secure function evaluation;garbled circuit protocol;zero-knowledge proof;commitment schemes;public-key;cryptography;hash functions; |
| Type (COBISS): | Master's thesis/paper |
| Study programme: | 0 |
| Embargo end date (OpenAIRE): | 1970-01-01 |
| Thesis comment: | Univ. v Ljubljani, Fak. za matematiko in fiziko, Oddelek za matematiko, Računalništvo in matematika - 2. stopnja |
| Pages: | IX, 49 str. |
| ID: | 11227549 |
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