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IMPLEMENTIMI I Ipv6 NË PROTOKOLLET E RRUGËTIMIT University of Business and Technology in Kosovo UBT Knowledge Center Theses and Dissertations Student Work Fall 9-2016 IMPLEMENTIMI I IPv6 NË PROTOKOLLET E RRUGËTIMIT Faton Ferizi Follow this and additional works at: https://knowledgecenter.ubt-uni.net/etd Part of the Computer Sciences Commons Programi për Shkenca Kompjuterike dhe Inxhinieri IMPLEMENTIMI I ONE-TIME PAD ALGORITMIT NË KRIPTOGRAFINË KLASIKE DHE KUANTIKE – ASPEKTI I SIGURISË Shkalla Bachelor Era Kuraja Shtator / 2016 Prishtinë Programi për Shkenca Kompjuterike dhe Inxhinieri Punim Diplome Viti akademik 2013 – 2016 Era Kuraja IMPLEMENTIMI I ONE-TIME PAD ALGORITMIT NË KRIPTOGRAFINË KLASIKE DHE KUANTIKE – ASPEKTI I SIGURISË Mentori: MSc. Shkëlqim Berisha Shtator / 2016 Ky punim është përpiluar dhe dorëzuar në përmbushjen e kërkesave të pjesshme për Shkallën Bachelor ABSTRAKT Shumica e informatave në ditët e sotme janë në formë digjitale, dhe njerëzit po mbështetetn gjithnjë e më shumë në to. Sidoqoftë, ruajtja e lehtë dhe çasja e thjeshtë dhe e shpejtë në ato informacione nuk është e mjaftueshme. Siguria e të dhënave është jashtëzakonsisht e rëndësishme dhe esenciale. Kriptografia është një ndër komponentet kyçe të sigurisë së informacionit. Mirëpo, sistemet kriptografike të ditëve të sotme kanë disa dobësi. Gjithashtu, pritet që me zhvillimin e teknologjisë dhe avancimin e sulmeve, sistemet kriptografike klasike të dobësohen. Si rrjedhojë, ofrohet një zgjidhje potenciale ndaj më e mirë që do t’i rezistonte përparimeve të sulmeve. Kriptografia kuantike prezantohet si zgjidhje e mundshme ndaj problemeve dhe dobësive aktuale dhe potenciale të kriptografisë klasike. Kriptografia kuantike nuk shqyrtohet si alternativë ndaj asaj klasike, por si shtesë që do të kombinohej me kriptografinë e deritanishme. Me anë të shfrytëzimit të koncepteve të mekanikës kuantike, shqyrtohen mundësitë e orfrimit të zgjidhjeve të sigurisë të cilat nuk është në gjendje t’i ofrojë kriptografia klasike. Kjo argumentohet duke bërë analizën e sigurisë dhe performancës së algoritmit One-Time Pad në kriptografi klasike, dhe duke e krahasuar me të njejtin algoritëm në kriptografi kuantike. Në fund, pas krahasimit dhe analizës së hollësishme dhe duke marë parasysh gjithë argumentet, arrihet në përfundime rreth ofrimit të kriptografisë kuantike si zgjidhje ndaj problemeve të kriptografisë klasike. Pra, përfundimisht shqyrtohet se a mund të përdoret kriptografia kuantike si zgjidhje ndaj problemeve të deritanishme dhe të ardhshme në sigurinë e informacionit. 1 MIRËNJOHJE DHE FALËNDERIME Do të dëshiroja të falënderoja profesor Shkëlqim Berisha për mbështetjen e vazhdueshme gjatë këtij punimi, motivimin dhe këshillat që ofronte gjatë gjithë kësaj kohe. Gjithashtu, do të dëshiroja të falënderoja familjen, për mbështetjen e vazhdueshme dhe ndihmesën e madhe që më kanë ofruar gjatë këtyre viteve. Së fundmi, dua të falënderoj të gjithë stafin akademik të UBT për motivimin, përkrahjen dhe punën e pa lodhshme që e bëjnë për të rritur nivelin akademik dhe profesional tek studentët. 2 PËRMBAJTJA LISTA E FIGURAVE ...................................................................................... 5 LISTA E TABELAVE ..................................................................................... 6 FJALORI I TERMAVE .................................................................................. 7 1 HYRJE ........................................................................................................ 8 2 SHQYRTIMI I LITERATURËS ........................................................... 10 2.1 Hyrje ...................................................................................................................... 10 2.2 Kriptografia klasike ............................................................................................... 11 2.2.1 Kriptografia simetrike dhe dobësitë ............................................................... 12 2.2.2 Kriptografia asimetrike dhe dobësitë .............................................................. 13 2.2.3 Kompjuterët kuantikë dhe dëmet që ata do t’i shkaktonin kriptografisë klasike 13 2.3 Kriptografia kuantike ............................................................................................. 15 2.3.1 Algoritmi One-Time Pad klasik ..................................................................... 15 2.3.2 Algoritmi One-Time Pad kuantik ................................................................... 17 3 DEKLARIMI I PROBLEMIT ............................................................... 18 3.1 Deklarimi i problemit të projektit .......................................................................... 18 3.2 Motivimi prapa projektit ........................................................................................ 19 3.3 Qëllimi dhe objektivat ........................................................................................... 20 3.3.1 Qëllimi i përgjithshëm .................................................................................... 20 3.3.2 Objektivat ....................................................................................................... 20 3.4 Struktura e temës së diplomës ............................................................................... 20 4 Metodologjia ............................................................................................ 22 4.1 One Time Pad — kriptografi klasike ..................................................................... 22 4.1.1 Mënyra e funksionimit ................................................................................... 23 3 4.1.2 Analiza e sigurisë dhe e performancës ........................................................... 27 4.1.3 Dobësitë e algoritmit One-Time Pad klasik ................................................... 28 4.1.4 Implementimet në jetën e përditëshme ........................................................... 31 4.2 One Time Pad — kriptografi kuantike .................................................................. 31 4.2.1 Mekanika kuantike dhe konceptet e saj të përdorura në kriptografi kuantike 32 4.2.2 Mënyra e funksionimit të One-Time Pad kuantik .......................................... 37 4.2.3 Analiza e sigurisë dhe e performancës ........................................................... 46 4.2.4 Dobësitë e algoritmit One-Time Pad kuantik ................................................. 47 4.2.5 Implementimet në jetën e përditëshme ........................................................... 50 4.3 Simulimi i algoritmit One-Time Pad në kriptografinë klasike dhe kuantike ......... 51 4.3.1 Simulimi i algoritmit One-Time Pad në kriptografinë klasike ....................... 51 4.3.2 Simulimi i algoritmit One-Time Pad në kriptografinë kuantike .................... 59 5 Rezultate ................................................................................................... 65 5.1 Rezultati i përgjithshëm pas krahasimit dhe analizimit të One-Time Pad në kriptografi klasike dhe në atë kuantike ............................................................................. 65 5.2 Përmbushja e qëllimit kryesor me anë të përmbushjes së objektivave .................. 66 6 Përfundime ............................................................................................... 69 6.1 Përfundimet e arritura për problemin e deklaruar dhe zgjidhja potenciale e tij..... 69 6.2 Puna e mëtutjeshme ............................................................................................... 69 7 Referenca .................................................................................................. 71 7.1 Referencat në tekst ................................................................................................. 71 7.2 Referencat në figura ............................................................................................... 77 7.3 Referencat në tabela ............................................................................................... 78 8 Appendices ............................................................................................... 79 8.1 Appendix A: Kodi i aplikacionit të thjeshtë që simulon OTP algoritmin klasik ... 79 8.2 Appendix B: Pjesë e kodit nga libraria QIT e punuar në Python, e cila përdoret nga QKD Simulator ................................................................................................................. 82 4 LISTA E FIGURAVE Figura 1: Shembull i një letre One-Time Pad Figura 2: Tabelë Vigenere Figura 3: Shembull i një “straddling checkerboard” tabele Figura 4: Biti klasik kundrejt bitit kuantik Figura 5: Ilustrimi grafik i polarizimit dhe bazave Figura 6: Biti kuantik si një foton i polarizuar Figura 7: Bitet e enkoduar në polarizimin e fotoneve Figura 8: QKD - kanali kuantik dhe kanali klasik publik Figura 9: Procesi i transmetimit të fotoneve dhe bitëve të enkoduar në to, dhe gjenerimi i çelësit fillestar të papërpunuar në protokollin BB84 Figura 10: Fazat e procesimit të çelësit të papërpunuar pas transmetimit Figura 11. Simulatori i algoritmit One-Time Pad klasik — procesi i enkriptimit Figura 12. Simulatori i algoritmit One-Time Pad klasik — procesi i dekriptimit Figura 13. Simulatori i algoritmit One-Time Pad klasik — procesi i enkriptimit dhe rezultatet 5 Figura 14. Simulatori i algoritmit One-Time Pad klasik — procesi i dekriptimit dhe rezultatet Figura 15. Rumkin — simulatori OTP Figura 16. Briangle — simulatori OTP Figura 17. QKD Simulator Figura 18. Konfigurimi fillestar i QKD simulator Figura 19. Rezultatet
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