ブロックチェーン 2.0 / Blockchains 2.0

2017年12月7日(木)、ブロックチェーンアカデミー「ブロックチェーン基盤技術 ブロックチェーン 2.0」にて使用したスライドです

Transcript

1. 2.0 CSO / SFC ks91@blockchainhub.co.jp 2.0 — — 2017-09-07 – p.1/41
2. ( ) SFC ( ) CSO (Chief Science Officer) 1993 M.Eng ( ) 2006 ( ) SFC 17 P2P 2011 → ( ) 2.0 — — 2017-09-07 – p.2/41
3. / Segregated Witness Proof of Stake 2.0 — — 2017-09-07 – p.3/41
4. 2.0 1. 2. Segregated Witness 3. 4. Proof of Stake ( ) 5. 6. 2.0 — — 2017-09-07 – p.4/41
5. 1. 2.0 — — 2017-09-07 – p.5/41
6. BTC / . . . 2.0 — — 2017-09-07 – p.6/41
7. EPOBC (Open Assets) OP_RETURN 2.0 — — 2017-09-07 – p.7/41
8. Open Assets Protocol (OAP) ( = ) 2.0 — — 2017-09-07 – p.8/41
9. ID ID (asset ID) 1. 2. 3. 160 = ID ( ) 4. base58check ‘A’ ( = 23) (asset quantity) BTC 2.0 — — 2017-09-07 – p.9/41
10. OP_RETURN PUSH 0x4f41 (‘OA’) = 2 0x0100 2 1∼9 LEB128 1∼9 2.0 — — 2017-09-07 – p.10/41
11. 2.0 — — 2017-09-07 – p.11/41
12. 2. Segregated Witness ( = ) (malleability) 2.0 — — 2017-09-07 – p.12/41
13. (witness) 2.0 — — 2017-09-07 – p.13/41
14. OP_RETURN PUSH 0xaa21a9ed 4 (witness) SHA-256 32 Merkle 2.0 — — 2017-09-07 – p.14/41
15. Merkle Tree (Bitcoin) Digest = double SHA-256 value Existence of a TX can be verified if a relevant subtree is provided 2.0 — — 2017-09-07 – p.15/41
16. (1) P2WPKH (version 0) (pay-to-(witnessed)-public-key-hash) witness ( ): < > < > scriptSig ( ): scriptPubKey ( ) 0 <20-byte > 20-byte < > < > CHECKSIG 2.0 — — 2017-09-07 – p.16/41
17. (2) P2WSH (version 0) (pay-to-(witnessed)-script-hash) witness: < 1 > <1 < 1 > < 2 > 2 CHECKMULTISIG> scriptSig: scriptPubKey 0 <32-byte > 32-byte 1-out-of-2 2.0 — — 2017-09-07 – p.17/41
18. SegWit https://bitcoincore.org/en/2016/01/26/segwit-benefits/ 2.0 — — 2017-09-07 – p.18/41
19. SegWit 2016 100 SegWit (95% ) . . . 2017 8 24 2.0 — — 2017-09-07 – p.19/41
20. 3. 2.0 — — 2017-09-07 – p.20/41
21. BIP (Bitcoin Improvement Proposal) ex. BIP 1 : BIP Purposes and Guidelines https://github.com/bitcoin/bips/blob/master/bip-0001.mediawiki ex. BIP 9 : Version bits with timeout and delay ex. BIP 141 : Segregated Witness (Consensus layer) TCP/IP RFC XMPP XEP 2.0 — — 2017-09-07 – p.21/41
22. Block Header Data Structure Field Description Size (bytes) Version 4 Digest Double SHA-256 value 32 Merkle root Double SHA-256 value 32 Time Seconds (since 1970-01-01T00:00 UTC) 4 Target Compressed format 4 Nonce Appropriate value 4 Merkle root is the digest of all TXs 2.0 — — 2017-09-07 – p.22/41
23. BIP 9 SegWit https://github.com/bitcoin/bips/blob/master/bip-0009/assignments.mediawiki MTP : Median Time Past ( 11 ) 2.0 — — 2017-09-07 – p.23/41
24. 4. Proof of Stake ( ) 2.0 — — 2017-09-07 – p.24/41
25. Proof of Stake ( ) ( ) 2.0 — — 2017-09-07 – p.25/41
26. Proof of Stake Hn (PD + id + t + . . .) ≤ 2n × balance d H n : n (ex. SHA-256 (n = 256)) PD : id : (ex. ) t : (ex. UNIX ( )) balance : d : (ex. ) PoW 2.0 — — 2017-09-07 – p.26/41
27. Proof of Stake 3 1. 2. “Nothing at Stake” 3. 51% 2.0 — — 2017-09-07 – p.27/41
28. : Proof of Stake Velocity Reddcoin 2.0 — — 2017-09-07 – p.28/41
29. Nothing at Stake - = 2.0 — — 2017-09-07 – p.29/41
30. Nothing at Stake - 100% Proof of Stake 2.0 — — 2017-09-07 – p.30/41
31. 51% 2.0 — — 2017-09-07 – p.31/41
32. Nothing at Stake ⇒ 2.0 — — 2017-09-07 – p.32/41
33. 5. . . . 2.0 — — 2017-09-07 – p.33/41
34. 2.0 — — 2017-09-07 – p.34/41
35. 2.0 — — 2017-09-07 – p.35/41
36. → ⇒ A. Back, et. al., “Enabling Blockchain Innovations with Pegged Sidechains”, 2014 2.0 — — 2017-09-07 – p.36/41
37. 6. 2.0 — — 2017-09-07 – p.37/41
38. 1 1 10 2 2.0 — — 2017-09-07 – p.38/41
39. A-B 2.0 — — 2017-09-07 – p.39/41
40. 2 2 ( ) Ripple Path 2.0 — — 2017-09-07 – p.40/41
41. 2.0 — — 2017-09-07 – p.41/41