Blockchain Beyond Bitcoin. Mark O Connell

Transcription

1 Mark O Connell mark@mkoconnell.com

2 SNIA Legal Notice The material contained in this tutorial is copyrighted by the SNIA unless otherwise noted. Member companies and individual members may use this material in presentations and literature under the following conditions: Any slide or slides used must be reproduced in their entirety without modification The SNIA must be acknowledged as the source of any material used in the body of any document containing material from these presentations. This presentation is a project of the SNIA Education Committee. Neither the author nor the presenter is an attorney and nothing in this presentation is intended to be, or should be construed as legal advice or an opinion of counsel. If you need legal advice or a legal opinion please contact your attorney. The information presented herein represents the author's personal opinion and current understanding of the relevant issues involved. The author, the presenter, and the SNIA do not assume any responsibility or liability for damages arising out of any reliance on or use of this information. NO WARRANTIES, EXPRESS OR IMPLIED. USE AT YOUR OWN RISK. Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights Reserved. 2

3 Abstract Blockchain is the name of a new class of distributed application which can coordinate independent operations across multiple machines in an untrusted network and produce a consensus result on both the correctness of the individual operations as well as the order in which the operations were executed. While the most well known use case for blockchain is Bitcoin, the technology itself has many other applications and implementations and use cases are arising in areas as diverse as international finance, B2B transactions, identity management, domain name registration, and many more. This tutorial will introduce the blockchain family of technologies, will discuss the technical aspects of the implementations and how consensus is achieved despite the lack of trust amongst the machines, will explore how this basic technology can be applied for non-currency related use cases, and will discuss alternative implementations of the technology and their advantages and disadvantages. Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights Reserved. 3

4 Definitions: Bitcoin vs Blockchain Digital currency No gov t control Cryptographically secured payments Ordered list of records Distributed ledger Decentralized Self-policing Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights 4 Reserved.

5 How does the bitcoin blockchain work? New tx Is it valid? Create a new block with this and other txs Try to add it to the chain Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights 5 Reserved. If successful, tell other blockchain nodes about the new block

6 Why does this work? Cryptographically signed (PKI) Sent to multiple nodes Must reference txs where money originated Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights Reserved.

7 Why does this work? Validate signature Validate origin txs Must reference txs where money originated Validated on multiple nodes Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights Reserved.

8 Why does this work? Block hash must match a certain pattern ~10 minutes to generate, by varying nonce Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights Reserved.

9 Why does this work? Other nodes validate: Txs are valid Hash matches pattern Links to final block Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights Reserved.

10 Why all the trouble? Validate multiple times? 10 minute Proof of Work? Designed for a no-trust environment Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights Reserved.

11 There s more to life than money Property deeds Artwork provenance Car title / ownership Medical history Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights 11Reserved.

12 There s more than one way Po-tay-to? Po-tah-to? Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights 12Reserved.

13 What makes a distributed ledger? Forgery protection Information distribution Redundant network Decentralized network Internal fraud protection Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights 13Reserved.

14 An example + Forgery protection - PKI Information distribution nodes chatter Redundant network mining rewards Decentralized network mining rewards Internal fraud protection Proof of Work Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights 14Reserved.

15 An example Forgery protection - PKI Information distribution nodes chatter whitelist Redundant network Interested participants Decentralized network Interested participants Internal fraud protection Whitelisted nodes Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights 15Reserved.

16 An example Forgery protection - PKI Information distribution Known node membership Redundant network Specific named nodes Decentralized network Specific named nodes Internal fraud protection Round robin mining Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights 16Reserved.

17 Proof of Work alternatives Once there is some trust: Round robin Proof of Stake Proportional to previously mined blocks Practical Byzantine Fault Tolerance 2/3rds of participants agree Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights 17Reserved.

18 A world of possibilities Identity B2B Smart Contracts DRM Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights 18Reserved.

19 Attribution & Feedback The SNIA Education Committee thanks the following Individuals for their contributions to this Tutorial. Authorship History Mark O Connell Updates: Additional Contributors Please send any questions or comments regarding this SNIA Tutorial to tracktutorials@snia.org Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights Reserved. 19

20 How does the Bitcoin blockchain work? 1. Send transaction to blockchain node (x bitcoins to Y) 2. Node validates the transaction 3. Node groups (ordered) transactions together 4. Node mines the group Competing against other miners 5. Node broadcasts its results If another miner got here first, go back to step 2 Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights 20Reserved.

21 How does the Bitcoin blockchain work? Tx 1 Tx 2 Tx 3 Tx 4 Tx 5 Tx N-1 Tx N Hash of block Hash of prior block Nonce Tx aa Tx ab Tx ac Tx ad Tx ae Tx ay Tx az Hash of block Hash of prior block Nonce Tx zkjdaa Tx zkjdab Tx zkjdac Tx zkjdad Tx zkjdae Tx zkjday Tx zkjdaz Hash of block Hash of prior block Nonce Tx new1 Tx new2 Tx new3 Tx new4 Tx new5 Tx new N-1 Tx new N TBD hash of block Hash of prior block TBD Nonce Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights 21Reserved.

22 How does the Bitcoin blockchain work? Tx 1 Tx aa Tx zkjdaa Tx 2 Tx ab Tx zkjdab Tx 3 Tx ac Tx zkjdac Tx 4 Tx ad Tx zkjdad Tx 5 Tx ae Tx zkjdae Tx N-1 Tx ay Tx zkjday Tx N Hash of block Tx az Hash of block Tx zkjdaz Hash of block Hash of prior block Hash of prior block Hash of prior block Nonce Nonce Nonce Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights 22Reserved.

23 New tx Is it valid? Create a new block with this and other txs Try to add it to the chain Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights 23Reserved.

24 How does the bitcoin blockchain work? New tx Is it valid? Create a new block with this and other txs Try to add it to the chain Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights 24Reserved. If successful, tell other blockchain nodes about the new block

25 Tutorial Preparation Guidelines Large size slide page number is deliberate Easier for audience to follow from handouts Keep slide-count to amount you can cover in time allotted Maximum slides for 60-minute session Maximum slides for 45-minute session Title, boilerplate (e.g. legal, Attribution & Feedback contents, and separator slides don t count against limit You may have extra slides in an Appendix (max. of ~30% extra) 3 levels of bullets maximum 4 to 6 Bullets: use 2 column text slide Use scheme colors for hyperlinks AVOID Moving or resizing the text area Changing fonts, point sizes or spacing Use color, bold and italics for emphasis Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights Reserved. 26

26 Tutorial Preparation Guidelines (cont.) Title Slide: List the presentation title, presenter name/company name; if a co -presenter, list name/company name (no addresses). Always include: Legal, Abstract, and Attribution & Feedback slides (do not delete these slides) Legal slide is #2 slide Abstract Slide is #3: View the sample abstract in SNIA Tutorial Preparation Guidelines presentation and modify your abstract to fit that format. Attribution & Feedback (authorship history & contributors) is the final slide before any appendix Please try to stay with template colors in case re-coloration is necessary. For information on approved colors, view Run spell check when done Choose Tools, Spelling in Powerpoint Choose Review, Spelling in Powerpoint 2007 Save your presentation as a Powerpoint 2007.pptx presentation file Refer to the FAQ for SNIA Tutorials General Information at Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights Reserved. 27

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28 Graphics Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights Reserved. 29

29 Graphics Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights Reserved. 30

30 Refer to Other Tutorials Use this icon to refer to other SNIA Tutorials where applicable Check out SNIA Tutorial: Enter Tutorial Title Here Approved SNIA Tutorial 2017 Storage Networking Industry Association. All Rights Reserved. 31