Digitalni potpis

master's thesis

• Author: Vesna Magjarević
• Mentor: Filip Najman (mentor)
• Committee member: Mladen Jurak (predsjednik povjerenstva)
• Committee member: Zvonimir Bujanović (član povjerenstva)
• Committee member: Maja Starčević (član povjerenstva)
• Committee member: Filip Najman (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Mathematics); Zagreb
• Defense date and country: 2017-07-18, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Mathematics

Abstract

Digitalni potpisi u komunikaciji osiguravaju autentičnost, integritet i neporecivost - svojstva koja su u doba internetske trgovine, sklapanja ugovora na daljinu i školovanja preko interneta neizmjerno važna. Sve češća uporaba digitalnih potpisa dovodi do povećanja broja napadača i njihovih pokušaja krivotvorenja tog potpisa. Uz to, mogućnosti računala se iz godine u godinu povećavaju i vrlo je moguće da algoritmi koji se danas smatraju sigurnima za nekoliko desetljeća to više neće biti. Upravo je zbog toga važno neprestano istraživati nove načine zaštite i preispitivati jesu li sadašnji dovoljno sigurni. U ovom radu navedeni su osnovni pojmovi vezani uz digitalni potpis, objašnjeni neki od sistema koji se koriste u komunikaciji u kojoj je prisutan digitalni potpis kao što su hash funkcije i digitalni certifikati te su predstavljene najpoznatije sheme za stvaranje digitalnih potpisa. Svaka od shema objašnjena je jednostavnim primjerom te su razmotreni najpoznatiji napadi na svaku od njih.

Abstract (english)

Digital signatures assure that communication between two or more parties is provided with the following basic cryptographic services: message authentication, data integrity and non-repudiation. Those features are crucial in communication nowadays, when most of the people can’t imagine day without internet shopping; when business transactions are made within seconds with people from around the world; when many students attend online courses and receive online certificates as proof of their knowledge. As digital signature usage becomes wider and bigger, there are more and more attackers that are looking for a way to forge signatures. Also, computer possibilities are growing every year: that is why we cannot be sure that the algorithms used today will be considered safe in a few decades. We must not stop questioning the security of algorithms used nowadays and exploring new means of protection. In this thesis we will cover basic definitions and explore some of the techniques used in digital signature algorithms. In chapters 2-6 we will see into some of the most popular digital signature schemes: RSA, ElGamal’s, DSA and ECDSA. For each of them, we will show a very basic example and consider the ways the enemy might try to attack the given scheme.

• Keywords: digitalni potpis; kriptografija; autentičnost; integritet; neporecivost
• Keywords (english): digital signature; cryptography; message authentication; data integrity; non-repudiation
• Language: croatian
• URN:NBN: urn:nbn:hr:217:501336
• Study programme: Title: Computer Science and Mathematics; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra računarstva i matematike (magistar/magistra računarstva i matematike)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-09-03 10:16:33