blockchains and adult education

Blockchains and Adult Education

Prof. John DomingueKnowledge Media InstituteThe Open UniversityUK

http://kmi.open.ac.uk/

http://blockchain.open.ac.uk/

BLOCKCHAINS IMPACT

Copyright http://dilbert.com/

Blockchain

3

WorldEconomicForumSurveyProjectsBlockchain‘TippingPoint’by2023

Santander:Blockchain TechCanSaveBanks$20BillionaYear

Bletchley:blockchainasaserviceinAzure

Everledgerwww.everledger.io

IBM: Device Democracy

http://www-935.ibm.com/services/multimedia/GBE03620USEN.pdf

Distributed Autonomous Organisations

BLOCKCHAIN ELEMENTS


Ledgers

What is a blockchain?

Ablockchain isapermissionless

distributeddatabase,basedonthebitcoin

protocolthatmaintainsa

continuouslygrowinglistoftransactional

datarecordshardenedagainsttamperingand

revision,evenbyoperatorsofthedata

store'snodes.

Theinitialandmostwidelyknown

applicationoftheblockchain technologyisthepublicledgeroftransactionsforbitcoinandtheinspirationofsimilardistributedledgersknownas

altchains.

Eachblockchain recordisenforced

cryptographicallyandhostedonmachines

workingasadatastore

Source:Wikipedia

Cryptographic Hash Function

https://en.wikipedia.org/wiki/Cryptographic_hash_function

Blockchain is a Linked List (1/2)

Ablockchaincanbethoughtofasalinkedlistoftransactionsthatisbuiltwithhashpointersinsteadofpointers

Source:Bitcoin andCryptocurrency Technologies- ArvindNarayanan,JosephBonneau, EdwardFelten,AndrewMiller, StevenGoldfeder

Peer to Peer Network

http://www.terndrup.net/2015/10/27/Building-a-P2P-Peer-Client-with-Node-js/

Who Next?Addeveryonehasacompletecopyofthedata

Proof of Work• Find x such that f(nonce + x) < t

(cryptographic hash)"Hello,world!0"=>1312af178c253f84028d480a6adc1e25e81caa44c749ec81976192e2ec934c64"Hello,world!1"=>e9afc424b79e4f6ab42d99c81156d3a17228d6e1eef4139be78e948a9332a7d8"Hello,world!2"=>ae37343a357a8297591625e7134cbea22f5928be8ca2a32aa475cf05fd4266b7 ...

"Hello,world!4248"=>6e110d98b388e77e9c6f042ac6b497cec46660deef75a55ebc7cfdf65cc0b965"Hello,world!4249"=>c004190b822f1669cac8dc37e761cb73652e7832fb814565702245cf26ebb9e6"Hello,world!4250"=>0000c3af42fc31103f1fdc0151fa747ff87349a4714df7cc52ea464e12dcd4e9

Blockchain is a Linked List (2/2)

Ablockchain actuallycontainstwodifferenthash structures.Thefirstisahashchainof

blocks thatlinks thedifferentblocks tooneanother.

Thesecond isinternaltoeachblockandisaMerkle Treeof

transactionswithintheblocks.

This allowsforefficientlyverifiableproofs thata

transactionwasincluded inablock.

Proof of Work

• Hard to outpace the entire rest of the network… a 51% attack could do it, but otherwise it is like buying thousands of lottery tickets –doesn’t help you that much!

Source:MarcEisenstadt ‘WhatisthegeniusbehindBitcoin’

Proof of Work

As you go back in time, an attacker would have to outpace the network for a longer amount of time to carry out a double spend attack, and replace a block.

Source:MarcEisenstadt ‘WhatisthegeniusbehindBitcoin’

BitCoin Mining

http://knkx.org/post/central-wash-home-nations-biggest-bitcoin-mine-more-coming

https://cointelegraph.com/news/the-inevitable-failure-of-proof-of-stake-blockchains-and-why-a-new-algorithm-is-needed

Ethereum Blockchain Platform

Ethereum isacryptocurrencyplatformandTuring-completeprogrammingframeworkintendedtoallowanetworkofpeerstoadministertheirownstateful user-createdsmartcontractsintheabsenceofcentralauthority.

Itfeaturesablockchain-basedvirtualmachinethatsecurelyrecordsandincentivizesthevalidationoftransactions,i.e.codeexecutions,madethroughacryptocurrencycalledether.

Ethereum takestheprimarydevelopmentsusedbyBitTorrent andBitcoin,thepeertopeernetworkandtheblockchain,andgeneralizestheminordertoallowdeveloperstousethesetechnologiesforanypurpose.

Source:Wikipedia



Ethereum isa100%opensourcesoftwareplatformtobuilddistributed,decentralizedapplications

Ethereum is100%peertopeer,censorship-proofandcorruption-proof.

Ethereumcanbeusedtobuildanything:Assetissuance,crowdfunding,domainregistration,titleregistration,predictionmarkets,internetofthings,voting,educationalcertificateissuingsystems,hundredsofapplications

Source:Ethereum slides- StephanTual andEthereum in40minites byVitalik Buterin

Ethereum Virtual Machine

Sources:Ethereum DevelopmentTutorial

TheEthereum VirtualMachinecanbethoughtofasalargedecentralizedcomputercontainingmillionsofobjects,called"accounts",whichhavetheabilitytomaintainaninternaldatabase,executecodeandtalktoeachother.Thereare2typesofAccounts:

Externallyownedaccount(EOA):anaccountcontrolledbyaprivatekeythathastheabilitytosendetherandmessagesfromit.

‘Smart’Contract:anaccountthathasitsowncode,andiscontrolledbycode.

AnyusercantriggeranactionbysendingatransactionfromanEOA,settingEthereum's wheelsinmotion.

Ifthedestinationof thetransactionisanotherEOA,thenthetransactionmaytransfersomeetherbutotherwisedoesnothing

However, ifthedestination isa‘Smart’Contract,thenthecontractinturnactivates,andautomaticallyrunsitscode.

State vs History

• State = “current” information – Account balances – Nonces– Contract code and contract storage

• History = things that happened – Transactions– Receipts

• Currently, all “full” nodes store state, some store history and some do not store history

Source:Devcon2slides– Ethereumin25MinutesbyVitalik Buterin

State

• State consists of key value mapping addresses to account objects

• Every account object contains 4 pieces of data: – Nonce – Balance – Code hash (code = empty string for private

key-controlled accounts) – Storage tree root


Gas

• Halting problem– Cannot tell whether or not a program will run

infinitely • Solution: charge fee per computational

step (“gas”)


What are Ethereum Contracts?‘Smart’contractsarecomputerprotocolsthatfacilitate,verify,orenforcethenegotiationorperformanceofacontract.

‘Smart’contractscanbepartiallyorfullyself-executing,self-enforcing,orboth.

SmartcontractsinEthereumhavetheabilitytoread/writetotheirowninternalstorage,readthestorageofthereceivedmessage,andsendmessagestoothercontracts,triggeringtheirexecutioninturn

Sources:WikipediaandEthereum Development TutorialandEthereum - Introduction toSmartContracts

Contracts in Ethereum

Maintainadatastorerepresenting

somethingwhichisusefultoeitherothercontractsortotheoutsideworld

Serveasasortofexternallyowned

accountwithamorecomplicatedaccess

policy

Manageanongoingcontractor

relationshipbetweenmultipleusers

Providefunctionstoothercontracts;

essentially servingasasoftwarelibrary.

ContractsinEthereum generallyserve4purposes:

source: Richard GendalBrown “ASimpleModelforSmartContracts”http://gendal.me/2015/02/10/a-simple-model-for-smart-contracts/

DApps

Source:Ethereum - StephanTual

AĐapp isadecentralised applicationwhichservessomespecificpurpose toitsusers,butwhichhastheimportantproperty thattheapplicationitselfdoesnotdependonanyspecificpartyexisting.

Ratherthanservingasafront-end forsellingorprovidingaspecificparty'sservices,aĐapp isatoolforpeopleandorganizationsondifferent sidesofaninteractionusetocometogetherwithoutanycentralizedintermediary.

ADapp consistsoftwoparts:afrontend, writteninHTMLorQML,andabackend(thinkofitasthe‘database’foryourfrontend).

DBrowsers

ItisanenduserinterfaceontotheEthereumblockchain.

ADBrowser ishowuserswillfindandinteractwithDApps

‘Mist’isthenameoftheEthereumDBrowser.

Characteristics of Blockchain DApps

• Shared database• Multiple writers• Absence of trust• Disintermediation• Transaction interaction• Set rules• Validators• Asset backing

http://www.multichain.com/blog/2015/11/avoiding-pointless-blockchain-project/

BLOCKCHAINS AND HIGHER EDUCATION


MSc Certificates on Blockchainhttp://digitalcurrency.unic.ac.cy/certificates

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“For example, after taking an examination to demonstrate his or her academic proficiency level, an individual could direct the testing organization to share the test results with one or more third-party evaluating organizations.”

“As education paradigms evolve, technological innovation is expected to diversify the ways in which tests are designed and individuals are evaluated. With this diversification and the changes it brings about, different evaluating organizations may come to utilize individuals' test results in different ways, each in accordance with its own evaluation methods.”

http://www.sony.net/SonyInfo/News/Press/201602/16-0222E/index.html

Demosofmoviesavailableat:http://blockchain.open.ac.uk/

Certification

CourseContract

Functions:

Storage:

enrol

unenrol

getStudents

studentsPaid [address=0.6,address=0….]students[address,address,address]

CourseAdministrationViewStudentView

Enrol for6ETH!

yourEthereumaddress

passwordtoprivatekey

Signing this transactionwill transfer6ETH+gas fromyouraccount.Estimatedgascostis0.02ETH.Maximumgascostisset to0.05ETH

Enrol

StudentEnrolmentPage

SignedTX

Unenrol Student

AdminEthereum address

Adminpasswordtoprivatekey

Signing this transactionwill transfer6ETH+gas fromcourseadminaccount.Estimatedgascost is0.02ETH.Maximumgascostis set to0.05ETH

Unenrol

CourseAdminPage

SignedTX

StudentList

(Listingstudents is afreetransaction)

CourseEnrolmentPage

SignedTX

StudentAddressArray

unenrolStudentAccount11

StudentAccount23

StudentAccount45

StudentAccount67

StudentAccount89

unenrol

unenrol

unenrol

unenrol

StudentAccount67

Course Smart Contract

JaneenrolsonanOpenLearn Course

Blockno:45566778


JaneenrolsonanOpenLearnCourse

Demosofmoviesavailableat:http://blockchain.open.ac.uk/

Peer Accreditation

Higher Education Disaggregation

Collaborations

Collaborations/Dialogue

• APII• Banking Standards Board• Blockchain Limited• Consensys• Ethcore• Fraunhofer• Imperial• Institute of the Future• Jisc• KPMG• MIT• Mozilla Open Badges (BadgeChain)• Southampton• UCL

Summary• Blockchains seem to be a revolutionary new platform for

sharing data at scale in a trusted fashion• Provides the basis for global distributed computation• Interestingly combines

– History– Rules– Value

• Has many application areas related to the recording and transference of value – Includes Higher Education and training

• Badges and certification• ePortfolios• Educational reputation centric currencies• Disaggregation

Acknowledgements• KMi@OU Implementation Team

– Michelle Bachler– Kevin Quick– Allan Third– Chris Valentine

• Discussants– Sören Auer, Fraunhofer– Adi Ben-Ari, Applied Blockchain– Carla Casilli, Mozilla Open Badges– Marc Eisenstadt, OU– Matthew English, Fraunhofer– Denis Gillet, EPFL– Hugh Halford-Thompson, Blockchain Tech Ltd– William Knottenbelt, Imperial College– Konstantin Kudryavtsev, Ethcore– Gary McKay, APII– Rebecca Migirov, Consensys– Titi Roman, Sintef– Philipp Schmidt, MIT Media Lab– Mike Sharples, OU– Elena Simperl, University of Southampton– Ashley Taylor, Consensys– Sergej Zerr, University of Southampton

• Graphics– Harriett Cornish, OU

blockchain.open.ac.uk

blockchains and adult education

Technology