Understanding Blockchain

Slides of PHP Reboot Meetup on Understanding Blockchain.

Transcript

1. BC BLOCK CHAIN Understanding Block Chain By Kapil Sharma
2. PHP Reboot • 14+ Years’ experience in Web Application development. • Open Source Contributor. • Managing PHP Reboot, Developers community in Pune since 2014. • Twitter: kapilsharmainfo • Linked In: kapilsharmainfo • Slides: speakerdeck.com/kapilsharma • YouTube: bit.ly/kapilyoutube Te c hni ca l A rc hi te c t at Ea ste r n E nte r p r i s e . Kapil Sharma Kapil Sharma 2
3. BC BLOCK CHAIN What is Block Chain? Concept Easy How to start
4. PHP Reboot Ch a i n of b l oc k BLOCK CHAIN Add a footer 4 Bl oc k = Data = = = = = = = = = = = = = Data : “ Na m e ” : ” Ka pi l S ha r m a ”. H a s h: 1234567890A BCDEF ( H exa d e c i m a l nu m b e r ) P revi ous H a s h: A BCDEF 0123456789 ( H exa d e c i m a l nu m b e r ) Data: One Previous: 0000 Hash: 1234 Data: Two Previous: 1234 Hash: 3456 Data: Three Previous: 3456 Hash: 12AB
5. PHP Reboot Kapil Sharma 5 Cryptography Immutable Ledger P2P Network Mining Consensus Protocol Signature
6. PHP Reboot Kapil Sharma 6 Cryptography Immutable Ledger P2P Network Mining Consensus Protocol Signature
7. BC BLOCK CHAIN Cryptography Let ’s m a ke a F i nge r pr i nt .
8. PHP Reboot Hash Cryptography Let ’s make a fingerprint. Kapil Sharma 8
9. PHP Reboot U nde rsta ndi ng S H A 256 Add a footer 9 Hash Cryptography •Cryptography Algorithm. •Requirements: • One way • Deterministic • Fast computation • The Avalanche effect • Must withstand collisions
10. PHP Reboot Kapil Sharma 10 Cryptography Immutable Ledger P2P Network Mining Consensus Protocol Signature
11. PHP Reboot Kapil Sharma 11 Cryptography Immutable Ledger P2P Network Mining Consensus Protocol Signature
12. BC BLOCK CHAIN Immutable Ledger A re gi st r y, t h at i s p e r m a n e nt .
13. PHP Reboot A re gi st r y, t h at i s p e r m a n e nt . Kapil Sharma 13 Immutable Ledger
14. PHP Reboot A re gi st r y, t h at i s p e r m a n e nt . Kapil Sharma 14 Immutable Ledger ₹ H om e re gi st r y exa m pl e .
15. PHP Reboot A re gi st r y, t h at i s p e r m a n e nt . Kapil Sharma 15 Immutable Ledger ₹ H om e re gi st r y exa m pl e .
16. PHP Reboot A re gi st r y, t h at i s p e r m a n e nt . Kapil Sharma 16 Immutable Ledger ₹ H om e re gi st r y exa m pl e .
17. PHP Reboot A re gi st r y, t h at i s p e r m a n e nt . Kapil Sharma 17 Immutable Ledger ₹ H om e re gi st r y exa m pl e . Problems?
18. PHP Reboot A re gi st r y, t h at i s p e r m a n e nt . Kapil Sharma 18 Immutable Ledger Bl oc k c ha i n exa m pl e . Data: PH: 000 Hash: 123 Data: PH: 123 Hash: 234 Data: PH: 234 Hash: 345
19. PHP Reboot A re gi st r y, t h at i s p e r m a n e nt . Kapil Sharma 19 Immutable Ledger Bl oc k c ha i n exa m pl e . Data: PH: 000 Hash: 123 Data: PH: 123 Hash: 234 Data: PH: 234 Hash: 345 Data: PH: 345 Hash: 456
20. PHP Reboot A re gi st r y, t h at i s p e r m a n e nt . Kapil Sharma 20 Immutable Ledger Bl oc k c ha i n exa m pl e . Data: PH: 000 Hash: 123 Data: PH: 123 Hash: 234 Data: PH: 234 Hash: 345 Data: PH: 345 Hash: 456 Data: PH: 456 Hash: 567 Data: PH: 567 Hash: 678
21. PHP Reboot A re gi st r y, t h at i s p e r m a n e nt . Kapil Sharma 21 Immutable Ledger Bl oc k c ha i n exa m pl e . Data: PH: 000 Hash: 123 Data: PH: 123 Hash: 234 Data: PH: 234 Hash: 345 Data: 1 PH: 345 Hash: 543 Data: PH: 456 Hash: 567 Data: PH: 567 Hash: 678
22. PHP Reboot A re gi st r y, t h at i s p e r m a n e nt . Kapil Sharma 22 Immutable Ledger Bl oc k c ha i n exa m pl e . Data: PH: 000 Hash: 123 Data: PH: 123 Hash: 234 Data: PH: 234 Hash: 345 Data: 1 PH: 345 Hash: 543 Data: PH: 456 Hash: 567 Data: PH: 567 Hash: 678
23. PHP Reboot A re gi st r y, t h at i s p e r m a n e nt . Kapil Sharma 23 Immutable Ledger Bl oc k c ha i n exa m pl e . Data: PH: 000 Hash: 123 Data: PH: 123 Hash: 234 Data: PH: 234 Hash: 345 Data: 1 PH: 345 Hash: 543 Data: PH: 456 Hash: 567 Data: PH: 567 Hash: 678 INVALID
24. PHP Reboot A re gi st r y, t h at i s p e r m a n e nt . Kapil Sharma 24 Immutable Ledger P robl e m s 1. Wh at stops u s e re ca l c u l ate h a s h of fol l owi n g b l oc ks ?
25. PHP Reboot A re gi st r y, t h at i s p e r m a n e nt . Kapil Sharma 25 Immutable Ledger P robl e m s Data: PH: 000 Hash: 123 Data: PH: 123 Hash: 234 Data: PH: 234 Hash: 345 Data: 1 PH: 345 Hash: 543 Data: PH: 456 Hash: 567 Data: PH: 567 Hash: 678 1. Wh at stops u s e re ca l c u l ate h a s h of fol l owi n g b l oc ks ?
26. PHP Reboot A re gi st r y, t h at i s p e r m a n e nt . Kapil Sharma 26 Immutable Ledger P robl e m s Data: PH: 000 Hash: 123 Data: PH: 123 Hash: 234 Data: PH: 234 Hash: 345 Data: 1 PH: 345 Hash: 543 Data: PH: 543 Hash: 765 Data: PH: 567 Hash: 678 1. Wh at stops u s e re ca l c u l ate h a s h of fol l owi n g b l oc ks ?
27. PHP Reboot A re gi st r y, t h at i s p e r m a n e nt . Kapil Sharma 27 Immutable Ledger P robl e m s 1. Wh at stops u s e re ca l c u l ate h a s h of fol l owi n g b l oc ks ? Data: PH: 000 Hash: 123 Data: PH: 123 Hash: 234 Data: PH: 234 Hash: 345 Data: 1 PH: 345 Hash: 543 Data: PH: 543 Hash: 765 Data: PH: 765 Hash: 876
28. PHP Reboot A re gi st r y, t h at i s p e r m a n e nt . Kapil Sharma 28 Immutable Ledger P robl e m s 1. Wh at stops u s e re ca l c u l ate h a s h of fol l owi n g b l oc ks ? Data: PH: 000 Hash: 123 Data: PH: 123 Hash: 234 Data: PH: 234 Hash: 345 Data: 1 PH: 345 Hash: 543 Data: PH: 543 Hash: 765 Data: PH: 765 Hash: 876 2. If we c h a n ge d a b l oc k m i sta ke n l y, h ow d o we re cove r i t ?
29. PHP Reboot Kapil Sharma 29 Cryptography Immutable Ledger P2P Network Mining Consensus Protocol Signature
30. PHP Reboot Kapil Sharma 30 Cryptography Immutable Ledger P2P Network Mining Consensus Protocol Signature
31. PHP Reboot M u l t i p l e p e e r cop i e s of s a m e b l oc k c h a i n . Kapil Sharma 31 P2P Network P robl e m s 1. Wh at stops u s e re ca l c u l ate h a s h of fol l owi n g b l oc ks ? Data: PH: 000 Hash: 123 Data: PH: 123 Hash: 234 Data: PH: 234 Hash: 345 Data: 1 PH: 345 Hash: 543 Data: PH: 543 Hash: 765 Data: PH: 765 Hash: 876 2. If we c h a n ge d a b l oc k m i sta ke n l y, h ow d o we re cove r i t ?
32. PHP Reboot 32 Data: PH: 000 Hash: 123 Data: PH: 123 Hash: 234 Data: PH: 234 Hash: 345 Data: 1 PH: 345 Hash: 543 Data: PH: 543 Hash: 765 Data: PH: 765 Hash: 876 Data: PH: 000 Hash: 123 Data: PH: 123 Hash: 234 Data: PH: 234 Hash: 345 Data: PH: 345 Hash: 456 Data: PH: 456 Hash: 567 Data: PH: 567 Hash: 678 Data: PH: 000 Hash: 123 Data: PH: 123 Hash: 234 Data: PH: 234 Hash: 345 Data: PH: 345 Hash: 456 Data: PH: 456 Hash: 567 Data: PH: 567 Hash: 678 M u l t i p l e p e e r cop i e s of s a m e b l oc k c h a i n . P2P Network
33. PHP Reboot M u l t i p l e p e e r cop i e s of s a m e b l oc k c h a i n . Kapil Sharma 33 P2P Network P robl e m s 1. Wh at stops u s e re ca l c u l ate h a s h of fol l owi n g b l oc ks ? Data: PH: 000 Hash: 123 Data: PH: 123 Hash: 234 Data: PH: 234 Hash: 345 Data: 1 PH: 345 Hash: 543 Data: PH: 543 Hash: 765 Data: PH: 765 Hash: 876 2. If we c h a n ge d a b l oc k m i sta ke n l y, h ow d o we re cove r i t ?
34. PHP Reboot Kapil Sharma 34 Cryptography Immutable Ledger P2P Network Mining Consensus Protocol Signature
35. PHP Reboot Kapil Sharma 35 Cryptography Immutable Ledger P2P Network Mining Consensus Protocol Signature
36. PHP Reboot Li ke i n gol d m i ni ng. Kapil Sharma 36 Mining
37. PHP Reboot Li ke i n gol d m i ni ng. Kapil Sharma 37 Mining BLOCK # 1 HASH: 12345 Previous Hash: 01234 DATA
38. PHP Reboot Li ke i n gol d m i ni ng. Kapil Sharma 38 Mining BLOCK # 1 HASH: 12345 Previous Hash: 01234 DATA Nonce
39. PHP Reboot Li ke i n gol d m i ni ng. Add a footer 39 Mining BLOCK # 1 HASH: 12345 Previous Hash: 01234 DATA Nonce
40. PHP Reboot S H A 256 Kapil Sharma 40 Hash Big 64 digit Hexa-decimal number
41. PHP Reboot F i ndi ng t he gol de n H A S H Kapil Sharma 41 Mining Big 64 digit Hexa-decimal number Smallest Largest
42. PHP Reboot F i ndi ng t he gol de n H A S H Kapil Sharma 42 Mining Big 64 digit Hexa-decimal number Smallest Largest 1234567890ABCDEF1234567890ABCDEF 1234567890ABCDEF1234567890ABCDEF
43. PHP Reboot F i ndi ng t he gol de n H A S H Kapil Sharma 43 Mining Big 64 digit Hexa-decimal number Smallest Largest 1234567890ABCDEF1234567890ABCDEF 1234567890ABCDEF1234567890ABCDEF 001234567890ABCDEF1234567890ABCD EF1234567890ABCDEF1234567890ABCD
44. PHP Reboot F i ndi ng t he gol de n H A S H Kapil Sharma 44 Mining Big 64 digit Hexa-decimal number Smallest Largest 1234567890ABCDEF1234567890ABCDEF 1234567890ABCDEF1234567890ABCDEF 001234567890ABCDEF1234567890ABCD EF1234567890ABCDEF1234567890ABCD 000034567890ABCDEF1234567890ABCD EF1234567890ABCDEF1234567890ABCD
45. PHP Reboot F i ndi ng t he gol de n H A S H Kapil Sharma 45 Mining Big 64 digit Hexa-decimal number Smallest Largest 1234567890ABCDEF1234567890ABCDEF 1234567890ABCDEF1234567890ABCDEF 001234567890ABCDEF1234567890ABCD EF1234567890ABCDEF1234567890ABCD 000034567890ABCDEF1234567890ABCD EF1234567890ABCDEF1234567890ABCD Target
46. PHP Reboot F i ndi ng t he gol de n H A S H Add a footer 46 Mining BLOCK # 1 HASH: 12345 Previous Hash: 01234 DATA Smallest Largest Target
47. PHP Reboot Kapil Sharma 47 Cryptography Immutable Ledger P2P Network Mining Consensus Protocol Signature
48. PHP Reboot Kapil Sharma 48 Cryptography Immutable Ledger P2P Network Mining Consensus Protocol Signature
49. PHP Reboot S ol vi ng t he P 2P net wor k probl e m s . Kapil Sharma 49 Consensus Protocol P robl e m s 1. F ra ud ( A ddi ng wrong bl oc k ) 2. Two b l oc ks a d d e d at a s a m e t i m e .
50. PHP Reboot Di ffe re nt ways of s ol vi n g F ra u d P rob l e m Kapil Sharma 50 Types of Consensus Protocol Type of Cons e ns us P rotocol s 1. P roof of Wor k ( P OW) ( Bi tcoi n) . 2. P roof of S ta ke ( P O S ) ( S m a r t Cont ra c t s ) 3. O t he rs .
51. PHP Reboot P roof of Wor k Kapil Sharma 51 Consensus Protocol H a s h ge n e rate d by s ol vi n g Cr yptogra p h i c Ch a l l e n ge . BLOCK # 1 HASH: 12345 Previous Hash: 01234 DATA Smallest Largest Target F i na nc i a l Inc e nt i ve 1. M i n e coi n s . 2. Tra n s a c t i on fe e .
52. PHP Reboot Two b l oc ks a d d e d at a s a m e t i m e Byza nt i ne fa u l t Tol e ra nc e Kapil Sharma 52 Consensus Protocol
53. PHP Reboot H ow t hey s ol ve d i t ? Kapil Sharma 53 Byzantine General’s Problem
54. PHP Reboot H ow t hey s ol ve d i t ? Kapil Sharma 54 Byzantine General’s Problem
55. PHP Reboot H ow t hey s ol ve d i t ? Kapil Sharma 55 Byzantine General’s Problem General Commander 1 Commander 2 Commander 3
56. PHP Reboot H ow t hey s ol ve d i t ? Kapil Sharma 56 Byzantine General’s Problem General Commander 1 Commander 2 Commander 3
57. PHP Reboot H ow t hey s ol ve d i t ? Kapil Sharma 57 Byzantine General’s Problem General Commander 1 Commander 2 Commander 3
58. PHP Reboot H ow t hey s ol ve d i t ? Kapil Sharma 58 Byzantine General’s Problem General Commander 1 Commander 2 Commander 3
59. PHP Reboot H ow t hey s ol ve d i t ? Kapil Sharma 59 Byzantine General’s Problem General Commander 1 Commander 2 Commander 3
60. PHP Reboot Def i n i t i on . Kapil Sharma 60 Byzantine fault tolerance If the fraud node is less than 1/3rd, network may reach the consensus.
61. PHP Reboot S ol vi ng t he P 2P net wor k probl e m s . Kapil Sharma 61 Consensus Protocol P robl e m s 1. F ra ud ( A ddi ng wrong bl oc k ) 2. Two b l oc ks a d d e d at a s a m e t i m e .
62. PHP Reboot Kapil Sharma 62 Cryptography Immutable Ledger P2P Network Mining Consensus Protocol Signature
63. PHP Reboot Kapil Sharma 63 Cryptography Immutable Ledger P2P Network Mining Consensus Protocol Signature
64. PHP Reboot En s u re m e s s a ge i s cor re c t . Kapil Sharma 64 (Digital) Signature P ubl i c a nd P r i vate keys 1. P r i vate key – Kn own onl y to you . 2. P ubl i c key – G e n e rate d f rom p r i vate key a n d di st r i bute d to t h e wh ol e wor l d . 1. Di st r i b u te you r p u b l i c key ( T h os e wh o n e e d to ve r i f y) 2. S i gn you r d oc u m e nt ( u s i n g p r i vate key) 3. S e n d d oc u m e nt a n d d i gi ta l s i gn at u re . 4. Re c e i ve r m ay ve r i f y d i gi ta l s i gn at u re by p u b l i c key.
65. PHP Reboot Kapil Sharma 65 Cryptography Immutable Ledger P2P Network Mining Consensus Protocol Signature
66. PHP Reboot Kapil Sharma 66 Cryptography Immutable Ledger P2P Network Mining Consensus Protocol Signature
67. PHP Reboot T ha nks to a nde rs 94 ( G i t H ub) Kapil Sharma 67 Code examples github.com/anders94/blockchain-demo github.com/anders94/public-private-key-demo
68. Thank You. Kapil Sharma • Twitter: kapilsharmainfo • Linked In: kapilsharmainfo • Website: www.phpreboot.com BC BLOCK CHAIN