A Developers View of Blockchain

This was one of the talks I gave in Finland.

Transcript

1. Martin Beeby - @thebeebs PRIMER ON BLOCKCHAIN A DEVELOPER
2. Martin Beeby @thebeebs WELCOME TO WHERE?
3. Martin Beeby @thebeebs FINLAND
4. Martin Beeby @thebeebs Software developer Since I was 16 Joined Oracle 7 months ago MARTIN BEEBY
5. Martin Beeby @thebeebs WHAT IS BLOCKCHAIN WHAT DEVELOPERS CAN DO WHAT WE OFFER
6. Martin Beeby @thebeebs ANTTON KIM DONALD THREE PEOPLE
7. Martin Beeby @thebeebs ALL WORK IN AN OFFICE
8. Martin Beeby @thebeebs ANTTON THE BAKER
9. Martin Beeby @thebeebs ANTTON KIM DONALD THEY BUY
10. Martin Beeby @thebeebs ANTTON KIM DONALD KIM BUYS
11. Martin Beeby @thebeebs ANTTON KIM DONALD ANTTON BUYS
12. Martin Beeby @thebeebs ANTTON KIM DONALD KIM SELLS
13. Martin Beeby @thebeebs ANTTON KIM DONALD PM ALSO BUYS
14. Martin Beeby @thebeebs Handsome Smart Remote Worker NEW PERSON JOINS THE TEAM
15. Martin Beeby @thebeebs MARTIN
16. Martin Beeby @thebeebs Transferring Money between them is now harder Easy to lose track of who owes what Lets build a database MONEY IS A PAIN
17. Martin Beeby @thebeebs Martin Controls it Each cake sale is a transaction The seller tells martin about the transaction. He records it CREATE A DATABASE
18. Martin Beeby @thebeebs ANTTON DONALD MARTIN KIM TRANSACTIONS
19. Martin Beeby @thebeebs Trust Required (Fraud) Transparency Central Control WHAT’S THE PROBLEM?
20. Martin Beeby @thebeebs MOST BUSINESS RUN THIS WAY BIG DATABASES ARE NOT A PROBLEM IF THERE IS TRUST
21. Martin Beeby @thebeebs MARTIN HAS A CAKE PROBLEM
22. Martin Beeby @thebeebs ANTTON DONALD MARTIN KIM DATABASE FOR EVERYONE
23. Martin Beeby @thebeebs Hard to keep in sync Hard to agree Hard to reach consensus PEOPLE COULD STILL DEFRAUD
24. Martin Beeby @thebeebs BLOCKCHAIN
25. Martin Beeby @thebeebs ANTTON DONALD MARTIN KIM PUBLIC AND PRIVATES Private Key Private Key Private Key Private Key Address 1 Address 2 Address 3 Address 6 Address 5
26. Martin Beeby @thebeebs Sender Amount Receiver Signed Address 1 5 Address 2 110101010 Address 2 4 Address 3 010101010 Address 3 3 Address 1 010011010 TRANSACTIONS
27. Martin Beeby @thebeebs Listen for transactions and validates them Order transactions into a block Creates and hashes blocks solving a maths problem related MINERS LISTEN FOR TRANSACTIONS Sender Receiver Signed Address 1 5 Address 2 110101010 Address 2 4 Address 3 010101010 Address 3 3 Address 1 010011010
28. Martin Beeby @thebeebs Solve a complex problem involving the hashing of the block Would be very expensive to try and present incorrect blocks Miners on bitcoin spend huge sums of money on electric PROOF OF WORK Jargon: A Consensus Algorithm
29. Martin Beeby @thebeebs Proof of Stake Proof of Elapsed Time Byzantine fault tolerant OTHER CONSENSUS ALGORITHM
30. Martin Beeby @thebeebs HASHING In west Philadelphia born and raised on the play ground was where I spent most of my days. Chilling 446F09C5D7DB665A 851077054EBC7067 56E372A32C8753F0 428B6671CA6CE449 In west helsinki born and raised on the play ground was where I spent most of my days. Chilling 223E8E360399E82A C97B37A73FA1F532 071F03D8A174FA56 6D44F1770CC37D9A SHA256
31. Martin Beeby @thebeebs
32. Martin Beeby @thebeebs Previous Hash of the block All the transactions to create a block Hash the block to create a unique Hash that represents everything YOU CANT CHANGE A BLOCK
33. Martin Beeby @thebeebs ANTTON DONALD MARTIN KIM OTHER NODES VERIFY
34. Martin Beeby @thebeebs MINERS THEN BUILD ANOTHER
35. Martin Beeby @thebeebs A list of transactions grouped into blocks Blocks chained together by knowing the previous hash Nothing can be altered, the slightest modification would be obvious A BLOCK CHAIN IS Jargon: Merkle Tree
36. Martin Beeby @thebeebs Smart Contracts Private Ledgers Build Apps WHAT CAN A DEVELOPER DO
37. Martin Beeby @thebeebs SMART CONTRACTS
38. Martin Beeby @thebeebs Gary decides to run an incentive. Every 100th cake customer get a reward. Contract Int x AddAddress(address) x = x + 1; If (x =100){ address.transfer(reward) } A PSUEDO CONTRACT
39. Martin Beeby @thebeebs A CONTRACT IS A TRANSACTION
40. Martin Beeby @thebeebs EVERY CALL TO THE CONTRACT REQUIRES A TRANSACTION
41. Martin Beeby @thebeebs MINERS EXECUTE THE PROGRAMS WHILST VERIFYING THE TRANSACTION
42. Martin Beeby @thebeebs The contract code is visible on the blockchain It can’t be changed by anyone All the calls are public and everyone can see the cake competition is fair ITS TRANSPARENT
43. Martin Beeby @thebeebs Bitcoin is great when you have zero trust in the nodes If you have no trust Proof of Work is a good compromise But the electricity cost is the compromise LEVELS OF TRUST
44. Martin Beeby @thebeebs You have trust and want to have decentralised consensus You want to see all the transitions and have distributed consensus You want to add and remove members. ENTERPRISE TRUST ISSUES CAN BE DIFFERENT
45. Martin Beeby @thebeebs https://www.hyperledger.org/members LINUX FOUNDATION
46. Martin Beeby @thebeebs Private and Permissioned Membership Service Provider (MSP) Pluggable: MSP/Consensus/Ledger Format HYPERLEDGER FABRIC Channels
47. Martin Beeby @thebeebs THE TUNA SUPPLY CHAIN From Sea to Table Lots of Fraud Could benefit from Transparency
48. Martin Beeby @thebeebs TUNA SUPPLY CHAIN Sarah is the fisherman who sustainably and legally catches tuna. Regulators verify that the tuna has been legally/sustainably caught. Miriam is a restaurant owner who wants legal/sustainable tuna Carl is another restaurant owner fisherman Sarah can sell tuna to.
49. Martin Beeby @thebeebs Sarah sells at different prices Privacy around deals Carl shouldn’t see Miriams price DEALS NEED TO BE PRIVATE
50. Martin Beeby @thebeebs
51. Martin Beeby @thebeebs package main import ( "fmt" "github.com/hyperledger/fabric/core/chaincode/shim" "github.com/hyperledger/fabric/protos/peer" ) http://thebeebs.co.uk/blockchain CHAINCODE
52. Martin Beeby @thebeebs type Tuna struct { Vessel string ‘json:"vessel"’ Datetime string ‘json:"datetime"’ Location string ‘json:"location"’ Holder string ‘json:"holder"’ } TUNA STRUCT
53. Martin Beeby @thebeebs func (s *SmartContract) initLedger(APIstub shim.ChaincodeStubInterface) sc.Response { tuna := []Tuna{ Tuna{Vessel: "923F", Location: "67.0006, -70.5476", Timestamp: "1504054225", Holder: "Miriam"}, Tuna{Vessel: "M83T", Location: "91.2395, -49.4594", Timestamp: "1504057825", Holder: "Dave"}, Tuna{Vessel: "T012", Location: "58.0148, 59.01391", Timestamp: "1493517025", Holder: "Igor"}, Tuna{Vessel: "P490", Location: "-45.0945, 0.7949", Timestamp: "1496105425", Holder: "Amalea"}, Tuna{Vessel: "S439", Location: "-107.6043, 19.5003", Timestamp: "1493512301", Holder: "Rafa"}, Tuna{Vessel: "J205", Location: "-155.2304, -15.8723", Timestamp: "1494117101", Holder: "Shen"}, Tuna{Vessel: "S22L", Location: "103.8842, 22.1277", Timestamp: "1496104301", Holder: "Leila"}, Tuna{Vessel: "EI89", Location: "-132.3207, -34.0983", Timestamp: "1485066691", Holder: "Yuan"}, Tuna{Vessel: "129R", Location: "153.0054, 12.6429", Timestamp: "1485153091", Holder: "Carlo"}, Tuna{Vessel: "49W4", Location: "51.9435, 8.2735", Timestamp: "1487745091", Holder: "Fatima"}, } i := 0 for i < len(tuna) { fmt.Println("i is ", i) tunaAsBytes, _ := json.Marshal(tuna[i]) APIstub.PutState(strconv.Itoa(i+1), tunaAsBytes) fmt.Println("Added", tuna[i]) i = i + 1 } return shim.Success(nil) } INIT
54. Martin Beeby @thebeebs
55. Martin Beeby @thebeebs func (s *SmartContract) Invoke(APIstub shim.ChaincodeStubInterface) sc.Response { // Retrieve the requested Smart Contract function and arguments function, args := APIstub.GetFunctionAndParameters() // Route to the appropriate handler function to interact with the ledger appropriately if function == "queryTuna" { return s.queryTuna(APIstub, args) } else if function == "initLedger" { return s.initLedger(APIstub) } else if function == "recordTuna" { return s.recordTuna(APIstub, args) } else if function == "queryAllTuna" { return s.queryAllTuna(APIstub) } else if function == "changeTunaHolder" { return s.changeTunaHolder(APIstub, args) } return shim.Error("Invalid Smart Contract function name.") } INVOKE
56. Martin Beeby @thebeebs func (s *SmartContract) queryTuna(APIstub shim.ChaincodeStubInterface, args []string) sc.Response { if len(args) != 1 { return shim.Error("Incorrect number of arguments. Expecting 1") } tunaAsBytes, _ := APIstub.GetState(args[0]) if tunaAsBytes == nil { return shim.Error(“Could not locate tuna”) } return shim.Success(tunaAsBytes) } QUERYTUNA
57. Martin Beeby @thebeebs RECORDTUNA func (s *SmartContract) recordTuna(APIstub shim.ChaincodeStubInterface, args []string) sc.Response { if len(args) != 5 { return shim.Error("Incorrect number of arguments. Expecting 5") } var tuna = Tuna{ Vessel: args[1], Location: args[2], Timestamp: args[3], Holder: args[4]} tunaAsBytes, _ := json.Marshal(tuna) err := APIstub.PutState(args[0], tunaAsBytes) if err != nil { return shim.Error(fmt.Sprintf("Failed to record tuna catch: %s", args[0])) } return shim.Success(nil) }
58. Martin Beeby @thebeebs func (s *SmartContract) changeTunaHolder(APIstub shim.ChaincodeStubInterface, args []string) sc.Response { if len(args) != 2 { return shim.Error("Incorrect number of arguments. Expecting 2") } tunaAsBytes, _ := APIstub.GetState(args[0]) if tunaAsBytes != nil { return shim.Error("Could not locate tuna") } tuna := Tuna{} json.Unmarshal(tunaAsBytes, &tuna) // Normally check that the specified argument is a valid holder of tuna but here we are skipping this check for this example. tuna.Holder = args[1] tunaAsBytes, _ = json.Marshal(tuna) err := APIstub.PutState(args[0], tunaAsBytes) if err != nil { return shim.Error(fmt.Sprintf("Failed to change tuna holder: %s", args[0])) } return shim.Success(nil) } CHANGETUNAHOLDER
59. Martin Beeby @thebeebs
60. Martin Beeby @thebeebs
61. Martin Beeby @thebeebs CALLING SOME CODE // changeTunaHolder - requires 2 argument var request = { chaincodeId:’tuna-app’, fcn: 'changeTunaHolder', args: ['1', 'Alex'], chainId: 'mychannel', txId: tx_id }; return channel.sendTransactionProposal(request);
62. Martin Beeby @thebeebs https://www.hyperledger.org/members HYPERLEDGER COMPOSER
63. @thebeebs The LIMITS OF MY RAIL CONSTRUCTION KNOWLEDGE
64. @thebeebs 70 A RAIL BUSINESS NETWORK For a wooden trainset • SafetyInspectors • TrackInstallers • TimberSupplier • SignallingCompanies • ProjectOwners • Add/Edit/Delete All Assets • SellWood Transfers Ownership of Wood to an Installer • InstallTrack Adds Lat, Long to the track. Fires a new track event. • SignOffTrack Adds a SafetyCertificate and assigns it to the track • SignOffSignal Adds a SafetyCertificate and assigns it to the signal • Track • Signal • Wood • SafetyDocument Participants ASSETS Transactions
65. @thebeebs Network Initializes
66. @thebeebs Add Participants • SafetyInspectors Signal Safety LTD Track Safe LTD • TrackInstallers Tracks R US LTD Install Tracks PLC • TimberSupplier Tims Timber LTD • SignallingCompanies Signals and Stuff LTD • ProjectOwners LS1 LTD Participants
67. @thebeebs 73 All Participants have THEIR own blockchain NODE TIMS TIMBER LTD LS1 LTD SIGNALS AND STUFF LTD TRACK SAFE LTD SIGNAL SAFETY LTD YOU CAN LIMIT WHAT THEY SEE
68. @thebeebs
69. @thebeebs SeLLSome WOOD
70. @thebeebs Date, Time Entry TYPE Participant 2018-05-23 09:01:00 Add Asset TimsTimber LTD View record 2018-05-23 09:01:10 Add Asset TimsTimber LTD View Record 2018-05-23 09:01:20 Add Asset TimsTimber LTD View Record 2018-05-23 09:01:30 Add Asset TimsTimber LTD View Record 2018-05-23 09:01:40 ADD ASSET TimsTimber LTD View Record
71. @thebeebs Install Some Track
72. @thebeebs Date, Time Entry TYPE Participant 2018-05-23 09:20:10 InstallTrack Tracks R US LTD View record 2018-05-23 09:20:20 InstallTrack Tracks R US LTD View Record InstallTrack - Adds Lat, Long to the track. Fires a new track event
73. @thebeebs Sign Off Track
74. @thebeebs Date, Time Entry TYPE Participant 2018-05-23 09:20:10 AddAsset SignOffTrack View record 2018-05-23 09:30:20 SIGNOFF SignOffTrack View Record
75. @thebeebs Install Some Signal
76. @thebeebs Sign Off Signal
77. @thebeebs Date, Time Entry TYPE Participant 2018-05-23 09:01:00 Add Asset TimsTimber LTD View record 2018-05-23 09:01:10 Add Asset TimsTimber LTD View Record 2018-05-23 09:01:20 Add Asset TimsTimber LTD View Record 2018-05-23 09:01:30 Add Asset TimsTimber LTD View Record 2018-05-23 09:01:40 ADD ASSET TimsTimber LTD View Record 2018-05-23 09:20:10 InstallTrack Tracks R US LTD View record 2018-05-23 09:20:20 InstallTrack Tracks R US LTD View Record 2018-05-23 09:20:10 AddAsset SignOffTrack View record 2018-05-23 09:30:20 SIGNOFF SignOffTrack View Record
78. @thebeebs 84 NETWORK nodeSCAN live ON THE SAME CLOUD OR DIFFERENT ONES. ON PREM TIMS TIMBER LTD ORACLE LS1 LTD MICROSOFT SIGNALS AND STUFF LTD TRACK SAFE LTD ANY HYPERLEDGER IBM SIGNAL SAFETY LTD
79. @thebeebs 85 ORACLE BLOCKCHAIN CLOUD SERVICE Built on opensource and compatible with any other provider
80. @thebeebs Multiple Use Cases Across Industries for Blockchain • Increase supply chain transparency • Reduction of counterfeit goods • Warranty management Retail & e-Commerce • Clearing and settlement • Domestic and cross-border payments • Loan origination and post-funding automation • Fraud prevention Finance • Supply chain finance • Track and trace ownership transfer • Compliance monitoring Logistics • Clinical trial management • Privacy and sharing of patient health records Healthcare • Asset management • Certification of renewable energy and emission allowances • Metering and billing Energy
81. @thebeebs DP WORLD Dubai Ports
82. Martin Beeby @thebeebs HTTP://THEBEEBS.CO.UK/BLOCKCHAIN
83. Martin Beeby @thebeebs WHY ORACLE?
84. Martin Beeby @thebeebs It’s open It’s Flexible I would love your feedback WE HAVE A CLOUD
85. Martin Beeby @thebeebs HTTP://THEBEEBS.UK/TRIAL $300
86. Martin Beeby @thebeebs CONTACT MARTIN BEEBY @thebeebs https://www.thebeebs.co.uk martin.beeby@oracle.com