ブロックチェーン連続講義 第2-6回 ブロックチェーン 2.0 / Blockchain 2.0

ブロックチェーンハブ主催で開催している第2期ブロックチェーン連続講義の第6回「ブロックチェーン 2.0」のスライドです。2016年9月2日(金) に使用しました。

Transcript

1. 2.0 2 6 SFC / CSO ks91@sfc.wide.ad.jp 2.0 — 2016-09-02 – p.1/42
2. 2.0 / Proof of Stake 2.0 — 2016-09-02 – p.2/42
3. 2.0 1. 2. 3. 2.0 — 2016-09-02 – p.3/42
4. 1. Abra – Uber – as is Proof of Existence – – 2.0 — 2016-09-02 – p.4/42
5. Abra Uber https://www.goabra.com Abra cf. Uber cf. Airbnb 2.0 — 2016-09-02 – p.5/42
6. Abra P2P ( ) ( ) (teller) → ATM → ATM BTC 2.0 — 2016-09-02 – p.6/42
7. Abra 1.5% Abra 0.25% Abra (by CEO) 2.0 — 2016-09-02 – p.7/42
8. BTC (USD 3 ) Abra UI ( ) “Don’t lose your phone!” ( ) Abra 2.0 — 2016-09-02 – p.8/42
9. Proof of Existence ( ) https://proofofexistence.com 2.0 — 2016-09-02 – p.9/42
10. Proof of Existence ( ) ( ) OP_RETURN OP_RETURN = ⇒ (burn = ( ) ) 0x444f4350524f4f46 (‘DOCPROOF’) SHA-256 Bitcoin blockchain explorer 5 mBTC (0.005 BTC) 2.0 — 2016-09-02 – p.10/42
11. 2. Segregated Witness 2.0 — 2016-09-02 – p.11/42
12. BTC / . . . 2.0 — 2016-09-02 – p.12/42
13. (Colored Coins) BTC ← 2.0 — 2016-09-02 – p.13/42
14. EPOBC (Open Assets) OP_RETURN 2.0 — 2016-09-02 – p.14/42
15. Open Assets Protocol (OAP) ( = ) 2.0 — 2016-09-02 – p.15/42
16. ID ID (asset ID) 1. 2. 3. 160 = ID ( ) 4. base58check ‘A’ ( = 23) (asset quantity) BTC 2.0 — 2016-09-02 – p.16/42
17. OP_RETURN PUSH 0x4f41 (‘OA’) = 2 0x0100 2 1∼9 LEB128 1∼9 2.0 — 2016-09-02 – p.17/42
18. 2.0 — 2016-09-02 – p.18/42
19. Segregated Witness ( = ) (malleability) 2.0 — 2016-09-02 – p.19/42
20. (witness) 2.0 — 2016-09-02 – p.20/42
21. OP_RETURN PUSH 0xaa21a9ed 4 (witness) SHA-256 32 Merkle 2.0 — 2016-09-02 – p.21/42
22. (1) P2WPKH (version 0) (pay-to-(witnessed)-public-key-hash) witness ( ): < > < > scriptSig ( ): scriptPubKey ( ) 0 <20-byte > 20-byte < > < > CHECKSIG 2.0 — 2016-09-02 – p.22/42
23. (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 — 2016-09-02 – p.23/42
24. 2.0 — 2016-09-02 – p.24/42
25. BIP (Bitcoin Improvement Proposal) ex. BIP 1 : BIP Purposes and Guidelines https://github.com/bitcoin/bips/blob/master/bip-0001.mediawiki ex. BIP 141 : Segregated Witness (Consensus layer) TCP/IP RFC XMPP XEP 2.0 — 2016-09-02 – p.25/42
26. 3. Proof of Stake ( ) 2.0 — 2016-09-02 – p.26/42
27. Proof of Stake ( ) 2.0 — 2016-09-02 – p.27/42
28. Proof of Stake ( ) ( ) 2.0 — 2016-09-02 – p.28/42
29. 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 — 2016-09-02 – p.29/42
30. Proof of Stake 3 1. 2. “Nothing at Stake” 3. 51% 2.0 — 2016-09-02 – p.30/42
31. : Proof of Stake Velocity Reddcoin 2.0 — 2016-09-02 – p.31/42
32. Nothing at Stake - 2.0 — 2016-09-02 – p.32/42
33. Nothing at Stake - 100% Proof of Stake 2.0 — 2016-09-02 – p.33/42
34. 51% 2.0 — 2016-09-02 – p.34/42
35. . . . 2.0 — 2016-09-02 – p.35/42
36. 2.0 — 2016-09-02 – p.36/42
37. 2.0 — 2016-09-02 – p.37/42
38. → ⇒ A. Back, et. al., “Enabling Blockchain Innovations with Pegged Sidechains”, 2014 2.0 — 2016-09-02 – p.38/42
39. 2.0 — 2016-09-02 – p.39/42
40. ( ) 1. 2. ( ) 2.0 — 2016-09-02 – p.40/42
41. OP_RETURN DNS ⇒ 2.0 — 2016-09-02 – p.41/42
42. 2.0 — 2016-09-02 – p.42/42