SlideShare a Scribd company logo
Blockchain – Beyond the Hype
Salman Baset
April 2nd, 2019
My goals for this talk…
• Blockchain is a new and emerging technology. As it is the case with any emerging technology,
there are claims and counter-claims on competing technologies, and their applications. Generally
speaking, there is a lot of confusion and lots of buzz words get thrown around.
• Eventually clarity will emerge, given time and effort by folks (remember OSI vs TCP/IP?)
• My goal is
• (1) to not make you more confused than you already were about blockchain
• (2) to help cut through confusion through examples, definitions, concepts, and solution examples.
2
Outline
• What is trust?
• What is blockchain?
• Design options for blockchain
• CAP theorem, perspectives of key folks in blockchain space
• Consensus algorithms
• Hyperledger
• Blockchain applications
• Hyperledger internships
3
“We have proposed a system for electronic
transactions without relying on trust.”
4
“We have proposed a system for electronic
transactions without relying on trust.”*
* https://bitcoin.org/bitcoin.pdf
Not true – says Bruce Schneier – Hyperledger Forum, December 2018
5
What is trust? (1/2)
Reference: Bruce Schneier’s example from Hyperledger Forum 2018
My building
lobby
(1)
(2) (3)
(4)
6
What is trust? (2/2)
• Can trust ever be eliminated?
• Trust is not eliminated. It is shifted.
• In the case of Bitcoin, the trust shifts from Governments and Banks to
a piece of software.
7
Bitcoin “paper” – Conclusion
We have proposed a system for electronic transactions without relying on trust.
We started with the usual framework of coins made from digital signatures, which
provides strong control of ownership, but is incomplete without a way to prevent
double-spending. To solve this, we proposed a peer-to-peer network using proof-
of-work to record a public history of transactions that quickly becomes
computationally impractical for an attacker to change if honest nodes control a
majority of CPU power. The network is robust in its unstructured simplicity. Nodes
work all at once with little coordination. They do not need to be identified, since
messages are not routed to any particular place and only need to be delivered on a
best effort basis. Nodes can leave and rejoin the network at will, accepting the
proof-of-work chain as proof of what happened while they were gone. They vote
with their CPU power, expressing their acceptance of valid blocks by working on
extending them and rejecting invalid blocks by refusing to work on them. Any
needed rules and incentives can be enforced with this consensus mechanism.
https://bitcoin.org/bitcoin.pdf 8
Bitcoin “paper” – Conclusion
We have proposed a system for electronic transactions without relying on trust.
We started with the usual framework of coins made from digital signatures, which
provides strong control of ownership, but is incomplete without a way to prevent
double-spending. To solve this, we proposed a peer-to-peer network using proof-
of-work to record a public history of transactions that quickly becomes
computationally impractical for an attacker to change if honest nodes control a
majority of CPU power. The network is robust in its unstructured simplicity. Nodes
work all at once with little coordination. They do not need to be identified, since
messages are not routed to any particular place and only need to be delivered on a
best effort basis. Nodes can leave and rejoin the network at will, accepting the
proof-of-work chain as proof of what happened while they were gone. They vote
with their CPU power, expressing their acceptance of valid blocks by working on
extending them and rejecting invalid blocks by refusing to work on them. Any
needed rules and incentives can be enforced with this consensus mechanism.
https://bitcoin.org/bitcoin.pdf
So, no non-electronic (aka paper) transactions? enuf said.
do not pay more than once really? what is work?
for ever?
distributed? anonymity is a goal ?
churn consensus algorithm
is fixed.
interesting the core …
9
The origins of the word blockchain…
Ehrsam, Meyer, Smith and Tuchman - Cipher Block Chaining (CBC) mode of operation - 1976
https://patents.google.com/patent/US4074066A/en
https://satoshi.nakamotoinstitute.org/emails/cryptography/6/
Hal Finney – “block chain” – two letter word. 2008-11-09 01:58:48 UTC
Earliest…
As recently
understood…
(approx.)
10
The emergence of “standard” definitions to buzz word terms…
• What is a standard definition?
• A definition created by a standards body such as National Institute of Standards and Technology (NIST) – US, or ISO.
The definition is typically first published as a draft version for feedback from public at large or a select group.
• Cloud Computing
• Utility Computing (McCarthy – 1961), Cloud computing (1996, Compaq Business plan per MIT TR), AWS 2006
• NIST.SP.800-145 - November 2009 (first draft), October 2011 (published).
• https://www.nist.gov/news-events/news/2011/10/final-version-nist-cloud-computing-definition-published
• ISO – ISO/IEC 17788:2014
• https://www.iso.org/standard/60544.html
• Blockchain (~2008)
• NIST.IR.8202 - Blockchain Technology Overview – January 2018 (first draft), October 2018 (published)
• https://csrc.nist.gov/publications/detail/nistir/8202/final
• ISO definition still in progress
• https://www.iso.org/standard/73771.html?browse=tc
11
What is blockchain?
• NIST.IR.8202
• (first two lines of intro) Blockchains are tamper evident and tamper resistant
digital ledgers implemented in a distributed fashion (i.e., without a central
repository) and usually without a central authority (i.e., a bank, company, or
government). At their basic level, they enable a community of users to record
transactions in a shared ledger within that community, such that under
normal operation of the blockchain network no transaction can be changed
once published.
What is a block? – grouping of transactions
What is a transaction? – a state changing mechanism
Does the definition clearly state append-only aspect of ledger?
12
What is a “ledger”?
• https://www.merriam-webster.com/dictionary/ledger
• a book containing accounts to which debits and credits are posted from books
of original entry
• a horizontal board used for vertical support (as in scaffolding)
• The ledger familiar to “most” of us…?
• Personal journal
13
Ledger vs. personal journal
Ledger Personal journal
Written on Paper with typically pen Paper, with pen or pencil
Can also be written with IT system (e.g., computer, SaaS) IT system (e.g., computer, SaaS)
Record of who made changes Important Not so much
Common primary application Recording monetary
transactions
Thoughts
Information lay out Structure (tabular), credit/debit,
with dates
Usually with dates
Information is appended? Typically, yes Typically, yes
Shared with others Employees (probably). Other
entities, no, unless IRS J
Depends J
14
What is a digital ledger?
• A ledger stored in a digital form
• On a (personal) computer or a set of computers
• Can contain data ranging from few bytes to peta bytes, and beyond
• What is distributed paper ledger?
• Create copies of paper and distribute it to relevant folks whenever there is a change?
• What is a distributed digital ledger? (or simply distributed ledger)
• Ledgers stored in digital form on a set of computers (e.g., cloud), where data
repository is not confined to a single computer (NIST: without central repository).
The structure of the information stored within the ledger depends on the
application.
15
Tamper evident and tamper resistant
• Immutable: Merriam-Webster
• https://www.merriam-webster.com/dictionary/immutable
• not capable of or susceptible to change
• Why do we write personal checks with a pen and not with a pencil?
• May be, no one writes personal checks these days J
• tamper evident and tamper resistant – to an extent
• Can a (distributed) digital ledger be changed?
• Of course!
• How to detect changes to a (distributed) digital ledger and prevent changes?
• Detect changes: audit logs
• Prevent changes: authz, authn (requires identity)
16
[Lack of] Central authority or central repository - Examples
• I run a database on my single machine.
• Central repository?
• Central authority?
• A big search engine has a massive farm of distributed machines connected over network, that work
together to respond to search queries.
• Central repository?
• Central authority?
• A music file-sharing system (Napster) has a central list of which users have files, but files are
downloaded peer-to-peer.
• Central authority?
• Central repository?
• A file-sharing network has a distributed index of files and file chunks.
• Central repository?
• Central authority?
17
Lets look at Bitcoin again
1. Decentralized – without central
authority?
• Hash power concentration
• https://www.blockchain.com/en/pools
• Crypto exchange concentration
• https://www.bbc.com/news/world-us-
canada-47203706
2. Distributed?
• Yeah
3. Anonymity?
• Public key per transaction
4. Energy efficiency?
• No
4. Non-crypto currency applications
• Not easy
5. Storage capacity per node (~30 GB)
• Ever increasing
6. Mining reward
• Decreasing with time. 12.5 bitcoins today
7. Transaction fees
• How a transaction ends up in a block
• Increasing with time
• Resistance to Sybil attacks
• Sybil attack: Create ‘fake identities’ to take
over portion of id space in a system
• Resistance: Yes, proof of work
18
Bitcoin: transaction types
Input 0 from
Alice, signed
by Alice
Output 0
“To Bob”
Output 1
“To Alice”
(change)
Common transaction
Alice pays Bob
1
2 Input 0
Output 0
Transaction aggregating funds
Input 1
Input N
3
Transaction distributing funds
Input 0
Output 0
Output 1
Output N
Payment is to a “public key”
19
Output => UTXO: unspent transaction output
Bitcoin: transactions are grouped into blocks
Block N
T1
T2: A -> B
T3
T4
Block N+1
B->C
Block N+2
C->D
H(N) H(N+1)
T1 T2 T3 T4
H() H() H() H()
H() H()
H(N) Mining: find a nonce such hash of merkle tree + nonce
is less than target and takes on avg 10 minutes to compute
Which transaction to include in block? Transaction fee higher
than some minimum. [decentralized or distributed?]
20
CAP theorem…
https://cryptographics.info/cryptographics/blockchain/cap-theorem/
21
The design options in Blockchain
• Scalability – as many nodes as possible
• Performance – write to chain as quickly as possible
• Anonymity (or conversely, strong identity) – not “easily traceable” back to entity
• Privacy – keep transactions data and transaction occurrence confidential among
involved parties
• Often informed by:
• Application-specific (crypto-currency) vs. agnostic
• One network to rule them all vs. many networks
• Environmental friendly (Bitcoin proof-of-work is energy inefficient)
22
The design options in Blockchain –
Scalability Triangle – Vitalik Buterin
Assume the total computational/bandwidth capacity of a
regular computer is O(c), and the total load of a blockchain is
O(n)
Decentralization: the system can run in an environment where
all nodes have O(c) resources
• Possible weakening: can have supernodes, but require only 1 of N supernodes to be
honest
Security: the system can survive attacks up to some specific
percentage of all
miners/validators (eg. 33%)
Scalability: the system can handle a load of O(n) > O(c)
• Computation
• State storage
• Bandwidth
https://vitalik.ca/files/Ithaca201807_Sharding.pdf
Scalability
Security
Decentralization
Claim: we can reach the middle of the triangle, though we do need to use some more complex tools to get
there (slide 6 of link below)
23
The design options in Blockchain –
Matt Corello – aka Bluematt - Bitcoin
• Trustlessness
• Scalability
• Identity (or lack of it)
http://diyhpl.us/wiki/transcripts/baltic-honeybadger/2018/trustlessness-scalability-and-directions-in-security-models/
24
The design options in Blockchain –
Hyperledger architecture group white paper
• Linux foundation project for creating open source permissioned blockchain networks
https://www.hyperledger.org/wp-content/uploads/2017/08/Hyperledger_Arch_WG_Paper_1_Consensus.pdf
Comparison of permissioned consensus approaches and standard proof of work
25
What is Finality?
• “Finality means that once a transaction is committed, it cannot be
reversed, i.e. the data cannot be rolled back to the previous state.
Different blockchain systems may provide different types of finality.
Typically, this is defined in the consensus protocol. Different types of
consensus exist, such as voting-based consensus with immediate
finality and lottery-based consensus with probabilistic finality.”
https://www.hyperledger.org/wp-content/uploads/2018/10/HL_Whitepaper_Metrics_PDF_V1.01.pdf
26
The design options in Blockchain –
CAP theorem equivalent for blockchain
• Decentralization, consistency, scalability
• http://msrg.org/publications/pdf_files/2018/bcbi-icdcs18-
Towards_Dependable,_Scalable,_an.pdf
27
What is CAP-theorem-equivalent for blockchain?
• Which blockchain?
• Which consensus algorithm?
• Which model?
• …
Will be a nice contribution….
28
Consensus algorithms
• Background
• Crash-tolerant consensus
• Byzantine consensus
• Nakamoto consensus (aka proof of work)
• Proof of stake
• Proof of elapsed time
https://hackernoon.com/a-hitchhikers-guide-to-consensus-algorithms-d81aae3eb0e3
Cachin, Vucolic - https://arxiv.org/pdf/1707.01873.pdf
29
Consensus algorithms - Background
• Lamport Byzantine generals problem [1982]
• Schneider – task of reaching and maintaining consensus among nodes
involves [1990]:
• A (deterministic) state machine that implements the logic of the service to be
replicated
• A consensus protocol to disseminate requests among the nodes, such that
each node executes the same sequence of requests on its instance of the
service.
• Traditionally in literature, consensus means reaching agreement on
single request (first) – atomic broadcasts provide agreement on
sequence of requests.
Cachin, Vucolic - https://arxiv.org/pdf/1707.01873.pdf
30
Crash-tolerant consensus
• Survive node crashes
• Progression in epochs or views with a unique leader for each view
• Replace leader
• N/2-1 failures
• Paxos (Zoo-keeper), Raft (etcd)
31
Byzantine consensus
• Practical Byzantine Fault Tolerance (PBFT)
• < n/3 (note the inequality) nodes can be malicious (or system must
have 3k+1 nodes for k nodes to be malicious)
• Commercial implementations hard to find
32
Nakamoto consensus aka proof of work
• (Nodes) vote with their CPU power, expressing their acceptance of
valid blocks by working on extending them and rejecting invalid
blocks by refusing to work on them. Any needed rules and incentives
can be enforced with this consensus mechanism.
33
Proof of stake
• Miners stake their tokens on which blocks are valid
• Miners spend their tokens on which fork to support
• If most people vote on the correct fork, miners who work on the
wrong fork can loose their stake
34
Distributed Ledger Technologies aka Blockchain categorization
Drive value of cryptocurrency Cryptocurrency for a business use-case
Blockchain for business
Anonymous Permissioned
CryptocurrencyNon-Cryptocurrency
Standards bodies and consortiums
35
Blockchain types
• Public blockchain
• Ledger is public, anyone can join?
• Private blockchain
• Ledger is private, anyone can join?
• Permissioned blockchain
• Ledger can be public or private, join requires consent of existing parties
36
What is Hyperledger?
• Hyperledger is an open source collaborative effort created to advance cross-industry blockchain
technologies. It is a global collaboration, hosted by The Linux Foundation, including leaders in finance,
banking, Internet of Things, supply chains, manufacturing and Technology.
• Launched in February 2016
https://www.hyperledger.org/about
Frameworks
Tools
Hyperledger
Indy
Hyperledger
Fabric
Hyperledger
Iroha
Hyperledger
Sawtooth
Hyperledger
Burrow
Hyperledger
Composer
Hyperledger
Explorer
Hyperledger
Cello
37
Hyperledger Projects Design Philosophy
• Consensus Layer
• Responsible for generating an agreement on the order and confirming the correctness of the set of transactions that constitute a block
• Smart Contract Layer
• Responsible for processing transaction requests and determining if transactions are valid by executing business logic.
• Communication Layer
• Responsible for peer-to-peer message transport between the nodes that participate in a shared ledger instance
• Data Store Abstraction (Ledger)
• Allows different data-stores to be used by other modules.
• Crypto Abstraction
• Allows different crypto algorithms or modules to be swapped out without affecting other modules.
• Identity Services
• Enables the establishment of a root of trust during setup of a blockchain instance, the enrollment and registration of identities or system entities during network
operation, and the management of changes like drops, adds, and revocations. Also, provides authentication and authorization.
• Policy Services
• Responsible for policy management of various policies specified in the system, such as the endorsement policy, consensus policy, or group management policy. It
interfaces and depends on other modules to enforce the various policies.
• APIs
• Enables clients and applications to interface to blockchains.
• Interoperation
• Supports the interoperation between different blockchain instances
38
Hyperledger Fabric releases
• https://github.com/hyperledger/fabric#releases
39
Overview of Hyperledger Fabric – Key Design Goals
• The four P’s
• Permissioned
• Privacy
• Pluggability
• Performance
40
Permissioned: Existing members determine who can join the network,
and update configuration
Public blockchains
• Download software and connect to network
• Configuration updated through developer
or community consensus
Hyperledger Fabric
• Policy-based mechanism to admit new
members and to update configuration
6/8 votes
(admit A: majority vote)
A
A
B
I want to invite A to network
A
B
A
B
A
B A
B
A
B
A
B
A
B
B
I want to invite B to network
A
B
3/8 votes
(reject B: majority vote)
Permissioned != Private 41
Privacy: Smart contract execution, and transaction data storage limited to a
set of nodes in the network based on policy
Public blockchains
• Every node runs smart contract
• Every full node can potentially have a full copy
of the ledger
Hyperledger Fabric
• A subset of nodes will run smart contracts
• The ledger updates are limited to set of
nodes (channel).
• Nodes in a channel can directly share private
data with subset of nodes (collections,
v1.1 feature)
SC
SC
SC
SC
SC
SC
SC
SC
SCSC
SC
Channel /
Private data collection
42
Pluggability: consensus, identity provider, crypto, data format, smart
contract language
Public blockchains
• Fixed or hard to change consensus algorithm (proof of work)
• Fixed encryption (e.g., secp256k1)
• Identity = public key - self
• Domain specific language (DSL) for writing smart contracts
Hyperledger Fabric
• Pluggable consensus algorithm (PBFT, Kafka)
• Pluggable crypto service provider
• Pluggable identity provider, zero knowledge
proofs
• General data format, key / value pair
• General purpose languages for writing smart contracts
(Javascript, Go)
43
Performance: transactions should commit quickly
Public blockchains
• Use proof of work / proof-of-stake as consensus
algorithm due to which it may be a while before
transactions are final (e.g., 60 minutes)
• Transaction commitments are often
probabilistic
Hyperledger Fabric
• Uses a voting based consensus mechanism
• Transaction commitments are immediately final
44
Ok, so where is mining in Hyperledger Fabric?
• There is no mining – however, the consensus algorithm is pluggable
• Consensus properties: safety, liveness
• The Kafka service used in Hyperledger Fabric is crash tolerant, but not Byzantine fault tolerant
source: https://www.hyperledger.org/wp-content/uploads/2017/08/Hyperledger_Arch_WG_Paper_1_Consensus.pdf
Hyperledger Fabric
Hyperledger Sawtooth
45
Hyperledger Fabric and Ethereum* – A summary
Hyperledger Fabric Ethereum
Open source Yes Yes
Live network No – create your own network Yes
Who can join the network? Depends on the rules created by network
creators – default majority vote (Permissioned)
Anyone
Smart contract language Javascript, Go
Smart contracts called chaincode in Fabric
Solidity, Vyper, LLL
Rogue smart contract prevention Explicit review and installation of smart code
before execution (no notion of gas)
Gas
Who executes smart contracts? Subset of nodes (or all) All nodes by default / channels
Who stores the blocks? (state visibility) Subset of nodes (or all) All nodes by default / channels
Consensus algorithm Execute-order-validate (voting) – no mining PoW, PoS
Identity X.509 certificate issued by membership service
provider of a peer. Contains public key
Public key
Incentive for running a node Business network Ether
*comparing apples to oranges? (open source software vs live public network)
46
Blockchain Applications
• Cryptocurrency (enuf said)
• Food Safety (provenance of goods from source to destination)
• The physical to digital correlation problem…
• Vitalik’s view on Blockchain applications (Dec 2018) tweet
• 50 examples of blockchain real world use cases
• Self-“Sovereign” Identity
47
Food Safety
Seller Crop / Quantity Buyer
Joe (farmer) sold crops (SKU#j1) Mangoes / 100 lbs Alice
Alice (distributor) sold crops (SKU#j1) Mangoes / 10 lbs Walmart
Alice (distributor) sold crops (SKU#j1) Mangoes / 90 lbs Kroger
Tina (farmer) sold crops (SKU#t1) Mangoes / 200 lbs Walmart
‘Joe’ the
farmer
‘Alice’ the distributor
“Tina” the
farmer
Seller Crop/Quantity Buye
r
Joe(farmer)soldcrops(SKU#j1) Mangoes/100lbs Alice
Alice(distributor)soldcrops(SKU#j1) Mangoes/10lbs Wal
mar
t
Alice(distributor)soldcrops(SKU#j1) Mangoes/90lbs Krog
er
Tina(farmer)soldcrops(SKU#t1) Mangoes/200lbs Wal
mar
t
Seller Crop/Quantity Buye
r
Joe(farmer)soldcrops(SKU#j1) Mangoes/100lbs Alice
Alice(distributor)soldcrops(SKU#j1) Mangoes/10lbs Wal
mar
t
Alice(distributor)soldcrops(SKU#j1) Mangoes/90lbs Krog
er
Tina(farmer)soldcrops(SKU#t1) Mangoes/200lbs Wal
mar
t
Seller Crop/Quantity Buye
r
Joe(farmer)soldcrops(SKU#j1) Mangoes/100lbs Alice
Alice(distributor)soldcrops(SKU#j1) Mangoes/10lbs Wal
mar
t
Alice(distributor)soldcrops(SKU#j1) Mangoes/90lbs Krog
er
Tina(farmer)soldcrops(SKU#t1) Mangoes/200lbs Wal
mar
t
Seller Crop/Quantity Buye
r
Joe(farmer)soldcrops(SKU#j1) Mangoes/100lbs Alice
Alice(distributor)soldcrops(SKU#j1) Mangoes/10lbs Wal
mar
t
Alice(distributor)soldcrops(SKU#j1) Mangoes/90lbs Krog
er
Tina(farmer)soldcrops(SKU#t1) Mangoes/200lbs Wal
mar
t
Seller Crop/Quantity Buye
r
Joe(farmer)soldcrops(SKU#j1) Mangoes/100lbs Alice
Alice(distributor)soldcrops(SKU#j1) Mangoes/10lbs Wal
mar
t
Alice(distributor)soldcrops(SKU#j1) Mangoes/90lbs Krog
er
Tina(farmer)soldcrops(SKU#t1) Mangoes/200lbs Wal
mar
t
Block N
Block N+1
Block N+2
Block N+3
48
Vitalik’s view on blockchain applications
• https://twitter.com/VitalikButerin/status/1072162014498148355
49
50+ examples of blockchains in real world
https://medium.com/@matteozago/50-examples-of-how-blockchains-are-taking-over-the-world-4276bf488a4b
50
Self-sovereign identity (SSI)
• What is SSI? (def. by Christopher Allen)
• http://www.lifewithalacrity.com/2016/04/the-path-to-self-soverereign-identity.html
• The principles
• Existence. Users must have an independent existence.
• Control. Users must control their identities.
• Access. Users must have access to their own data.
• Transparency. Systems and algorithms must be transparent.
• Persistence. Identities must be long-lived.
• Portability. Information and services about identity must be transportable.
• Interoperability. Identities should be as widely usable as possible.
• Consent. Users must agree to the use of their identity.
• Minimalization. Disclosure of claims must be minimized.
• Protection. The rights of users must be protected.
• Decentralized identity foundation (https://identity.foundation/)
• Sovrin foundation (https://sovrin.org/) – Columbia can be a steward node
(https://sovrin.org/stewards/)
51

More Related Content

What's hot

Nist.ir.8202
Nist.ir.8202Nist.ir.8202
Nist.ir.8202
IT Strategy Group
 
Delloite custodian whitepaper
Delloite custodian whitepaperDelloite custodian whitepaper
Delloite custodian whitepaper
IT Strategy Group
 
China blockchain-roadmap - Blockchain-Based-Service-Network-BSN-introductory-...
China blockchain-roadmap - Blockchain-Based-Service-Network-BSN-introductory-...China blockchain-roadmap - Blockchain-Based-Service-Network-BSN-introductory-...
China blockchain-roadmap - Blockchain-Based-Service-Network-BSN-introductory-...
Rein Mahatma
 
The coin tree summarized 10-15
The coin tree   summarized 10-15The coin tree   summarized 10-15
The coin tree summarized 10-15
RedChip Companies, Inc.
 
Blockchain in banking bucharest meetup
Blockchain in banking   bucharest meetupBlockchain in banking   bucharest meetup
Blockchain in banking bucharest meetup
Alex Proca
 
Blockchain Primer - Founder Collective - December 2017
Blockchain Primer - Founder Collective - December 2017Blockchain Primer - Founder Collective - December 2017
Blockchain Primer - Founder Collective - December 2017
Parul Singh
 
Blockchain technology-report-final
Blockchain technology-report-finalBlockchain technology-report-final
Blockchain technology-report-final
RishabhMalik32
 
Patent Blockchain People Bank of China (PBOC)
Patent Blockchain People Bank of China (PBOC)Patent Blockchain People Bank of China (PBOC)
Patent Blockchain People Bank of China (PBOC)
Rein Mahatma
 
Blockchain As An Enabler_16 July 2016_David Lee_Final
Blockchain As An Enabler_16 July 2016_David Lee_FinalBlockchain As An Enabler_16 July 2016_David Lee_Final
Blockchain As An Enabler_16 July 2016_David Lee_Final
David Lee Kuo Chuen 李国权
 
State of Blockchain Q1 2016
State of Blockchain Q1 2016State of Blockchain Q1 2016
State of Blockchain Q1 2016
CoinDesk
 
Blockchain technology revolutionising technology
Blockchain technology revolutionising technologyBlockchain technology revolutionising technology
Blockchain technology revolutionising technology
Suman Nayak
 
David shrier, weige wu, alex pentland mit blockchain
David shrier, weige wu, alex pentland mit blockchainDavid shrier, weige wu, alex pentland mit blockchain
David shrier, weige wu, alex pentland mit blockchain
IT Strategy Group
 
Blockchain Technology Report 2018
Blockchain Technology Report 2018Blockchain Technology Report 2018
Blockchain Technology Report 2018
Ranvijay Singh
 
Jp morgan blockchain bitcoin
Jp morgan blockchain bitcoinJp morgan blockchain bitcoin
Jp morgan blockchain bitcoin
Rein Mahatma
 
Stacks 2.0 Introduction ($STX)
Stacks 2.0 Introduction ($STX)Stacks 2.0 Introduction ($STX)
Stacks 2.0 Introduction ($STX)
Trevor Owens
 
Blockchain case study powerpoints: Brief intro
Blockchain case study powerpoints: Brief introBlockchain case study powerpoints: Brief intro
Blockchain case study powerpoints: Brief intro
Shane Ninai
 
Blockchain for Executives, Entrepreneurs and Investors
Blockchain for Executives, Entrepreneurs and InvestorsBlockchain for Executives, Entrepreneurs and Investors
Blockchain for Executives, Entrepreneurs and Investors
Fenbushi Capital
 
Blockchain technology and applications from a financial perspective
Blockchain technology and applications from a financial perspectiveBlockchain technology and applications from a financial perspective
Blockchain technology and applications from a financial perspective
Vittorio Zinetti
 
Exploring Cryptocurrency Remittance
Exploring Cryptocurrency RemittanceExploring Cryptocurrency Remittance
Exploring Cryptocurrency Remittance
XRPTalk
 
Introduction to Blockchain Technology
Introduction to Blockchain TechnologyIntroduction to Blockchain Technology
Introduction to Blockchain Technology
snehal_152
 

What's hot (20)

Nist.ir.8202
Nist.ir.8202Nist.ir.8202
Nist.ir.8202
 
Delloite custodian whitepaper
Delloite custodian whitepaperDelloite custodian whitepaper
Delloite custodian whitepaper
 
China blockchain-roadmap - Blockchain-Based-Service-Network-BSN-introductory-...
China blockchain-roadmap - Blockchain-Based-Service-Network-BSN-introductory-...China blockchain-roadmap - Blockchain-Based-Service-Network-BSN-introductory-...
China blockchain-roadmap - Blockchain-Based-Service-Network-BSN-introductory-...
 
The coin tree summarized 10-15
The coin tree   summarized 10-15The coin tree   summarized 10-15
The coin tree summarized 10-15
 
Blockchain in banking bucharest meetup
Blockchain in banking   bucharest meetupBlockchain in banking   bucharest meetup
Blockchain in banking bucharest meetup
 
Blockchain Primer - Founder Collective - December 2017
Blockchain Primer - Founder Collective - December 2017Blockchain Primer - Founder Collective - December 2017
Blockchain Primer - Founder Collective - December 2017
 
Blockchain technology-report-final
Blockchain technology-report-finalBlockchain technology-report-final
Blockchain technology-report-final
 
Patent Blockchain People Bank of China (PBOC)
Patent Blockchain People Bank of China (PBOC)Patent Blockchain People Bank of China (PBOC)
Patent Blockchain People Bank of China (PBOC)
 
Blockchain As An Enabler_16 July 2016_David Lee_Final
Blockchain As An Enabler_16 July 2016_David Lee_FinalBlockchain As An Enabler_16 July 2016_David Lee_Final
Blockchain As An Enabler_16 July 2016_David Lee_Final
 
State of Blockchain Q1 2016
State of Blockchain Q1 2016State of Blockchain Q1 2016
State of Blockchain Q1 2016
 
Blockchain technology revolutionising technology
Blockchain technology revolutionising technologyBlockchain technology revolutionising technology
Blockchain technology revolutionising technology
 
David shrier, weige wu, alex pentland mit blockchain
David shrier, weige wu, alex pentland mit blockchainDavid shrier, weige wu, alex pentland mit blockchain
David shrier, weige wu, alex pentland mit blockchain
 
Blockchain Technology Report 2018
Blockchain Technology Report 2018Blockchain Technology Report 2018
Blockchain Technology Report 2018
 
Jp morgan blockchain bitcoin
Jp morgan blockchain bitcoinJp morgan blockchain bitcoin
Jp morgan blockchain bitcoin
 
Stacks 2.0 Introduction ($STX)
Stacks 2.0 Introduction ($STX)Stacks 2.0 Introduction ($STX)
Stacks 2.0 Introduction ($STX)
 
Blockchain case study powerpoints: Brief intro
Blockchain case study powerpoints: Brief introBlockchain case study powerpoints: Brief intro
Blockchain case study powerpoints: Brief intro
 
Blockchain for Executives, Entrepreneurs and Investors
Blockchain for Executives, Entrepreneurs and InvestorsBlockchain for Executives, Entrepreneurs and Investors
Blockchain for Executives, Entrepreneurs and Investors
 
Blockchain technology and applications from a financial perspective
Blockchain technology and applications from a financial perspectiveBlockchain technology and applications from a financial perspective
Blockchain technology and applications from a financial perspective
 
Exploring Cryptocurrency Remittance
Exploring Cryptocurrency RemittanceExploring Cryptocurrency Remittance
Exploring Cryptocurrency Remittance
 
Introduction to Blockchain Technology
Introduction to Blockchain TechnologyIntroduction to Blockchain Technology
Introduction to Blockchain Technology
 

Similar to Blockchain - Beyond the Hype

Blockchain and Hook model of engagement
Blockchain and Hook model of engagement Blockchain and Hook model of engagement
Blockchain and Hook model of engagement
Rajeev Soni
 
Secure and Smart IoT
Secure and Smart IoT Secure and Smart IoT
Secure and Smart IoT
Ahmed Banafa
 
The deep skill of blockchain david lee 27_april2017 final
The deep skill of blockchain david lee 27_april2017 finalThe deep skill of blockchain david lee 27_april2017 final
The deep skill of blockchain david lee 27_april2017 final
David Lee Kuo Chuen 李国权
 
blockchain-introduction-public.pptx
blockchain-introduction-public.pptxblockchain-introduction-public.pptx
blockchain-introduction-public.pptx
AyushVerma584677
 
Blockchain and Bitcoin
Blockchain and BitcoinBlockchain and Bitcoin
Blockchain and Bitcoin
M Shamim Iqbal
 
Decipher openseminar (1)
Decipher openseminar (1)Decipher openseminar (1)
Decipher openseminar (1)
Jae-Yun Kim
 
Blockchain and Cryptocurrencies
Blockchain and CryptocurrenciesBlockchain and Cryptocurrencies
Blockchain and Cryptocurrencies
nimeshQ
 
C13_blockchain introduction public (1).pptx
C13_blockchain introduction public (1).pptxC13_blockchain introduction public (1).pptx
C13_blockchain introduction public (1).pptx
haifaazka
 
module-1.pptx
module-1.pptxmodule-1.pptx
module-1.pptx
Raju385766
 
Introduction to Blockchain and Smart Contracts
Introduction to Blockchain and Smart ContractsIntroduction to Blockchain and Smart Contracts
Introduction to Blockchain and Smart Contracts
Saad Zaher
 
dfgsdjghkjsdhfg.pptx
dfgsdjghkjsdhfg.pptxdfgsdjghkjsdhfg.pptx
dfgsdjghkjsdhfg.pptx
hdfkjshgkjdfhg
 
A technical Introduction to Blockchain.
A technical Introduction to Blockchain.A technical Introduction to Blockchain.
A technical Introduction to Blockchain.
Dev
 
blockchain-161025100639.pptx
blockchain-161025100639.pptxblockchain-161025100639.pptx
blockchain-161025100639.pptx
Praveenkumar155694
 
Blockchain and BPM - Reflections on Four Years of Research and Applications
Blockchain and BPM - Reflections on Four Years of Research and ApplicationsBlockchain and BPM - Reflections on Four Years of Research and Applications
Blockchain and BPM - Reflections on Four Years of Research and Applications
Ingo Weber
 
Blockchain Security and Privacy
Blockchain Security and PrivacyBlockchain Security and Privacy
Blockchain Security and Privacy
Anil John
 
Blockchain Technology for Public and Commercial Libraries
Blockchain Technology for Public and Commercial LibrariesBlockchain Technology for Public and Commercial Libraries
Blockchain Technology for Public and Commercial Libraries
David Nzoputa Ofili
 
IoT and Blockchain Convergence
IoT and Blockchain ConvergenceIoT and Blockchain Convergence
IoT and Blockchain Convergence
Ahmed Banafa
 
Blockchain, Ethereum and ConsenSys
Blockchain, Ethereum and ConsenSysBlockchain, Ethereum and ConsenSys
Blockchain, Ethereum and ConsenSys
WithTheBest
 
IoT and Blockchain Challenges and Risks
IoT and Blockchain Challenges and RisksIoT and Blockchain Challenges and Risks
IoT and Blockchain Challenges and Risks
Ahmed Banafa
 
Blockchain English
Blockchain EnglishBlockchain English
Blockchain English
Ming Sun
 

Similar to Blockchain - Beyond the Hype (20)

Blockchain and Hook model of engagement
Blockchain and Hook model of engagement Blockchain and Hook model of engagement
Blockchain and Hook model of engagement
 
Secure and Smart IoT
Secure and Smart IoT Secure and Smart IoT
Secure and Smart IoT
 
The deep skill of blockchain david lee 27_april2017 final
The deep skill of blockchain david lee 27_april2017 finalThe deep skill of blockchain david lee 27_april2017 final
The deep skill of blockchain david lee 27_april2017 final
 
blockchain-introduction-public.pptx
blockchain-introduction-public.pptxblockchain-introduction-public.pptx
blockchain-introduction-public.pptx
 
Blockchain and Bitcoin
Blockchain and BitcoinBlockchain and Bitcoin
Blockchain and Bitcoin
 
Decipher openseminar (1)
Decipher openseminar (1)Decipher openseminar (1)
Decipher openseminar (1)
 
Blockchain and Cryptocurrencies
Blockchain and CryptocurrenciesBlockchain and Cryptocurrencies
Blockchain and Cryptocurrencies
 
C13_blockchain introduction public (1).pptx
C13_blockchain introduction public (1).pptxC13_blockchain introduction public (1).pptx
C13_blockchain introduction public (1).pptx
 
module-1.pptx
module-1.pptxmodule-1.pptx
module-1.pptx
 
Introduction to Blockchain and Smart Contracts
Introduction to Blockchain and Smart ContractsIntroduction to Blockchain and Smart Contracts
Introduction to Blockchain and Smart Contracts
 
dfgsdjghkjsdhfg.pptx
dfgsdjghkjsdhfg.pptxdfgsdjghkjsdhfg.pptx
dfgsdjghkjsdhfg.pptx
 
A technical Introduction to Blockchain.
A technical Introduction to Blockchain.A technical Introduction to Blockchain.
A technical Introduction to Blockchain.
 
blockchain-161025100639.pptx
blockchain-161025100639.pptxblockchain-161025100639.pptx
blockchain-161025100639.pptx
 
Blockchain and BPM - Reflections on Four Years of Research and Applications
Blockchain and BPM - Reflections on Four Years of Research and ApplicationsBlockchain and BPM - Reflections on Four Years of Research and Applications
Blockchain and BPM - Reflections on Four Years of Research and Applications
 
Blockchain Security and Privacy
Blockchain Security and PrivacyBlockchain Security and Privacy
Blockchain Security and Privacy
 
Blockchain Technology for Public and Commercial Libraries
Blockchain Technology for Public and Commercial LibrariesBlockchain Technology for Public and Commercial Libraries
Blockchain Technology for Public and Commercial Libraries
 
IoT and Blockchain Convergence
IoT and Blockchain ConvergenceIoT and Blockchain Convergence
IoT and Blockchain Convergence
 
Blockchain, Ethereum and ConsenSys
Blockchain, Ethereum and ConsenSysBlockchain, Ethereum and ConsenSys
Blockchain, Ethereum and ConsenSys
 
IoT and Blockchain Challenges and Risks
IoT and Blockchain Challenges and RisksIoT and Blockchain Challenges and Risks
IoT and Blockchain Challenges and Risks
 
Blockchain English
Blockchain EnglishBlockchain English
Blockchain English
 

More from Salman Baset

GDPR considerations for blockchain solution architects.
GDPR considerations for blockchain solution architects.GDPR considerations for blockchain solution architects.
GDPR considerations for blockchain solution architects.
Salman Baset
 
GDPR and Blockchain
GDPR and BlockchainGDPR and Blockchain
GDPR and Blockchain
Salman Baset
 
Container Security
Container SecurityContainer Security
Container Security
Salman Baset
 
Dissecting Open Source Cloud Evolution: An OpenStack Case Study
Dissecting Open Source Cloud Evolution: An OpenStack Case StudyDissecting Open Source Cloud Evolution: An OpenStack Case Study
Dissecting Open Source Cloud Evolution: An OpenStack Case Study
Salman Baset
 
Open Source Cloud Technologies
Open Source Cloud TechnologiesOpen Source Cloud Technologies
Open Source Cloud Technologies
Salman Baset
 
Cloud SLAs: Present and Future
Cloud SLAs: Present and FutureCloud SLAs: Present and Future
Cloud SLAs: Present and Future
Salman Baset
 
SPEC Cloud (TM) IaaS 2016 Benchmark
SPEC Cloud (TM) IaaS 2016 BenchmarkSPEC Cloud (TM) IaaS 2016 Benchmark
SPEC Cloud (TM) IaaS 2016 Benchmark
Salman Baset
 
A Survey of Container Security in 2016: A Security Update on Container Platforms
A Survey of Container Security in 2016: A Security Update on Container PlatformsA Survey of Container Security in 2016: A Security Update on Container Platforms
A Survey of Container Security in 2016: A Security Update on Container Platforms
Salman Baset
 
Unraveling Docker Security: Lessons From a Production Cloud
Unraveling Docker Security: Lessons From a Production CloudUnraveling Docker Security: Lessons From a Production Cloud
Unraveling Docker Security: Lessons From a Production Cloud
Salman Baset
 

More from Salman Baset (9)

GDPR considerations for blockchain solution architects.
GDPR considerations for blockchain solution architects.GDPR considerations for blockchain solution architects.
GDPR considerations for blockchain solution architects.
 
GDPR and Blockchain
GDPR and BlockchainGDPR and Blockchain
GDPR and Blockchain
 
Container Security
Container SecurityContainer Security
Container Security
 
Dissecting Open Source Cloud Evolution: An OpenStack Case Study
Dissecting Open Source Cloud Evolution: An OpenStack Case StudyDissecting Open Source Cloud Evolution: An OpenStack Case Study
Dissecting Open Source Cloud Evolution: An OpenStack Case Study
 
Open Source Cloud Technologies
Open Source Cloud TechnologiesOpen Source Cloud Technologies
Open Source Cloud Technologies
 
Cloud SLAs: Present and Future
Cloud SLAs: Present and FutureCloud SLAs: Present and Future
Cloud SLAs: Present and Future
 
SPEC Cloud (TM) IaaS 2016 Benchmark
SPEC Cloud (TM) IaaS 2016 BenchmarkSPEC Cloud (TM) IaaS 2016 Benchmark
SPEC Cloud (TM) IaaS 2016 Benchmark
 
A Survey of Container Security in 2016: A Security Update on Container Platforms
A Survey of Container Security in 2016: A Security Update on Container PlatformsA Survey of Container Security in 2016: A Security Update on Container Platforms
A Survey of Container Security in 2016: A Security Update on Container Platforms
 
Unraveling Docker Security: Lessons From a Production Cloud
Unraveling Docker Security: Lessons From a Production CloudUnraveling Docker Security: Lessons From a Production Cloud
Unraveling Docker Security: Lessons From a Production Cloud
 

Recently uploaded

LF Energy Webinar: Carbon Data Specifications: Mechanisms to Improve Data Acc...
LF Energy Webinar: Carbon Data Specifications: Mechanisms to Improve Data Acc...LF Energy Webinar: Carbon Data Specifications: Mechanisms to Improve Data Acc...
LF Energy Webinar: Carbon Data Specifications: Mechanisms to Improve Data Acc...
DanBrown980551
 
Lee Barnes - Path to Becoming an Effective Test Automation Engineer.pdf
Lee Barnes - Path to Becoming an Effective Test Automation Engineer.pdfLee Barnes - Path to Becoming an Effective Test Automation Engineer.pdf
Lee Barnes - Path to Becoming an Effective Test Automation Engineer.pdf
leebarnesutopia
 
Getting the Most Out of ScyllaDB Monitoring: ShareChat's Tips
Getting the Most Out of ScyllaDB Monitoring: ShareChat's TipsGetting the Most Out of ScyllaDB Monitoring: ShareChat's Tips
Getting the Most Out of ScyllaDB Monitoring: ShareChat's Tips
ScyllaDB
 
"Scaling RAG Applications to serve millions of users", Kevin Goedecke
"Scaling RAG Applications to serve millions of users",  Kevin Goedecke"Scaling RAG Applications to serve millions of users",  Kevin Goedecke
"Scaling RAG Applications to serve millions of users", Kevin Goedecke
Fwdays
 
PRODUCT LISTING OPTIMIZATION PRESENTATION.pptx
PRODUCT LISTING OPTIMIZATION PRESENTATION.pptxPRODUCT LISTING OPTIMIZATION PRESENTATION.pptx
PRODUCT LISTING OPTIMIZATION PRESENTATION.pptx
christinelarrosa
 
GNSS spoofing via SDR (Criptored Talks 2024)
GNSS spoofing via SDR (Criptored Talks 2024)GNSS spoofing via SDR (Criptored Talks 2024)
GNSS spoofing via SDR (Criptored Talks 2024)
Javier Junquera
 
Essentials of Automations: Exploring Attributes & Automation Parameters
Essentials of Automations: Exploring Attributes & Automation ParametersEssentials of Automations: Exploring Attributes & Automation Parameters
Essentials of Automations: Exploring Attributes & Automation Parameters
Safe Software
 
QR Secure: A Hybrid Approach Using Machine Learning and Security Validation F...
QR Secure: A Hybrid Approach Using Machine Learning and Security Validation F...QR Secure: A Hybrid Approach Using Machine Learning and Security Validation F...
QR Secure: A Hybrid Approach Using Machine Learning and Security Validation F...
AlexanderRichford
 
Containers & AI - Beauty and the Beast!?!
Containers & AI - Beauty and the Beast!?!Containers & AI - Beauty and the Beast!?!
Containers & AI - Beauty and the Beast!?!
Tobias Schneck
 
Demystifying Knowledge Management through Storytelling
Demystifying Knowledge Management through StorytellingDemystifying Knowledge Management through Storytelling
Demystifying Knowledge Management through Storytelling
Enterprise Knowledge
 
AWS Certified Solutions Architect Associate (SAA-C03)
AWS Certified Solutions Architect Associate (SAA-C03)AWS Certified Solutions Architect Associate (SAA-C03)
AWS Certified Solutions Architect Associate (SAA-C03)
HarpalGohil4
 
Must Know Postgres Extension for DBA and Developer during Migration
Must Know Postgres Extension for DBA and Developer during MigrationMust Know Postgres Extension for DBA and Developer during Migration
Must Know Postgres Extension for DBA and Developer during Migration
Mydbops
 
Day 2 - Intro to UiPath Studio Fundamentals
Day 2 - Intro to UiPath Studio FundamentalsDay 2 - Intro to UiPath Studio Fundamentals
Day 2 - Intro to UiPath Studio Fundamentals
UiPathCommunity
 
What is an RPA CoE? Session 2 – CoE Roles
What is an RPA CoE?  Session 2 – CoE RolesWhat is an RPA CoE?  Session 2 – CoE Roles
What is an RPA CoE? Session 2 – CoE Roles
DianaGray10
 
"Choosing proper type of scaling", Olena Syrota
"Choosing proper type of scaling", Olena Syrota"Choosing proper type of scaling", Olena Syrota
"Choosing proper type of scaling", Olena Syrota
Fwdays
 
Christine's Product Research Presentation.pptx
Christine's Product Research Presentation.pptxChristine's Product Research Presentation.pptx
Christine's Product Research Presentation.pptx
christinelarrosa
 
"Frontline Battles with DDoS: Best practices and Lessons Learned", Igor Ivaniuk
"Frontline Battles with DDoS: Best practices and Lessons Learned",  Igor Ivaniuk"Frontline Battles with DDoS: Best practices and Lessons Learned",  Igor Ivaniuk
"Frontline Battles with DDoS: Best practices and Lessons Learned", Igor Ivaniuk
Fwdays
 
ScyllaDB Tablets: Rethinking Replication
ScyllaDB Tablets: Rethinking ReplicationScyllaDB Tablets: Rethinking Replication
ScyllaDB Tablets: Rethinking Replication
ScyllaDB
 
Northern Engraving | Nameplate Manufacturing Process - 2024
Northern Engraving | Nameplate Manufacturing Process - 2024Northern Engraving | Nameplate Manufacturing Process - 2024
Northern Engraving | Nameplate Manufacturing Process - 2024
Northern Engraving
 
Leveraging the Graph for Clinical Trials and Standards
Leveraging the Graph for Clinical Trials and StandardsLeveraging the Graph for Clinical Trials and Standards
Leveraging the Graph for Clinical Trials and Standards
Neo4j
 

Recently uploaded (20)

LF Energy Webinar: Carbon Data Specifications: Mechanisms to Improve Data Acc...
LF Energy Webinar: Carbon Data Specifications: Mechanisms to Improve Data Acc...LF Energy Webinar: Carbon Data Specifications: Mechanisms to Improve Data Acc...
LF Energy Webinar: Carbon Data Specifications: Mechanisms to Improve Data Acc...
 
Lee Barnes - Path to Becoming an Effective Test Automation Engineer.pdf
Lee Barnes - Path to Becoming an Effective Test Automation Engineer.pdfLee Barnes - Path to Becoming an Effective Test Automation Engineer.pdf
Lee Barnes - Path to Becoming an Effective Test Automation Engineer.pdf
 
Getting the Most Out of ScyllaDB Monitoring: ShareChat's Tips
Getting the Most Out of ScyllaDB Monitoring: ShareChat's TipsGetting the Most Out of ScyllaDB Monitoring: ShareChat's Tips
Getting the Most Out of ScyllaDB Monitoring: ShareChat's Tips
 
"Scaling RAG Applications to serve millions of users", Kevin Goedecke
"Scaling RAG Applications to serve millions of users",  Kevin Goedecke"Scaling RAG Applications to serve millions of users",  Kevin Goedecke
"Scaling RAG Applications to serve millions of users", Kevin Goedecke
 
PRODUCT LISTING OPTIMIZATION PRESENTATION.pptx
PRODUCT LISTING OPTIMIZATION PRESENTATION.pptxPRODUCT LISTING OPTIMIZATION PRESENTATION.pptx
PRODUCT LISTING OPTIMIZATION PRESENTATION.pptx
 
GNSS spoofing via SDR (Criptored Talks 2024)
GNSS spoofing via SDR (Criptored Talks 2024)GNSS spoofing via SDR (Criptored Talks 2024)
GNSS spoofing via SDR (Criptored Talks 2024)
 
Essentials of Automations: Exploring Attributes & Automation Parameters
Essentials of Automations: Exploring Attributes & Automation ParametersEssentials of Automations: Exploring Attributes & Automation Parameters
Essentials of Automations: Exploring Attributes & Automation Parameters
 
QR Secure: A Hybrid Approach Using Machine Learning and Security Validation F...
QR Secure: A Hybrid Approach Using Machine Learning and Security Validation F...QR Secure: A Hybrid Approach Using Machine Learning and Security Validation F...
QR Secure: A Hybrid Approach Using Machine Learning and Security Validation F...
 
Containers & AI - Beauty and the Beast!?!
Containers & AI - Beauty and the Beast!?!Containers & AI - Beauty and the Beast!?!
Containers & AI - Beauty and the Beast!?!
 
Demystifying Knowledge Management through Storytelling
Demystifying Knowledge Management through StorytellingDemystifying Knowledge Management through Storytelling
Demystifying Knowledge Management through Storytelling
 
AWS Certified Solutions Architect Associate (SAA-C03)
AWS Certified Solutions Architect Associate (SAA-C03)AWS Certified Solutions Architect Associate (SAA-C03)
AWS Certified Solutions Architect Associate (SAA-C03)
 
Must Know Postgres Extension for DBA and Developer during Migration
Must Know Postgres Extension for DBA and Developer during MigrationMust Know Postgres Extension for DBA and Developer during Migration
Must Know Postgres Extension for DBA and Developer during Migration
 
Day 2 - Intro to UiPath Studio Fundamentals
Day 2 - Intro to UiPath Studio FundamentalsDay 2 - Intro to UiPath Studio Fundamentals
Day 2 - Intro to UiPath Studio Fundamentals
 
What is an RPA CoE? Session 2 – CoE Roles
What is an RPA CoE?  Session 2 – CoE RolesWhat is an RPA CoE?  Session 2 – CoE Roles
What is an RPA CoE? Session 2 – CoE Roles
 
"Choosing proper type of scaling", Olena Syrota
"Choosing proper type of scaling", Olena Syrota"Choosing proper type of scaling", Olena Syrota
"Choosing proper type of scaling", Olena Syrota
 
Christine's Product Research Presentation.pptx
Christine's Product Research Presentation.pptxChristine's Product Research Presentation.pptx
Christine's Product Research Presentation.pptx
 
"Frontline Battles with DDoS: Best practices and Lessons Learned", Igor Ivaniuk
"Frontline Battles with DDoS: Best practices and Lessons Learned",  Igor Ivaniuk"Frontline Battles with DDoS: Best practices and Lessons Learned",  Igor Ivaniuk
"Frontline Battles with DDoS: Best practices and Lessons Learned", Igor Ivaniuk
 
ScyllaDB Tablets: Rethinking Replication
ScyllaDB Tablets: Rethinking ReplicationScyllaDB Tablets: Rethinking Replication
ScyllaDB Tablets: Rethinking Replication
 
Northern Engraving | Nameplate Manufacturing Process - 2024
Northern Engraving | Nameplate Manufacturing Process - 2024Northern Engraving | Nameplate Manufacturing Process - 2024
Northern Engraving | Nameplate Manufacturing Process - 2024
 
Leveraging the Graph for Clinical Trials and Standards
Leveraging the Graph for Clinical Trials and StandardsLeveraging the Graph for Clinical Trials and Standards
Leveraging the Graph for Clinical Trials and Standards
 

Blockchain - Beyond the Hype

  • 1. Blockchain – Beyond the Hype Salman Baset April 2nd, 2019
  • 2. My goals for this talk… • Blockchain is a new and emerging technology. As it is the case with any emerging technology, there are claims and counter-claims on competing technologies, and their applications. Generally speaking, there is a lot of confusion and lots of buzz words get thrown around. • Eventually clarity will emerge, given time and effort by folks (remember OSI vs TCP/IP?) • My goal is • (1) to not make you more confused than you already were about blockchain • (2) to help cut through confusion through examples, definitions, concepts, and solution examples. 2
  • 3. Outline • What is trust? • What is blockchain? • Design options for blockchain • CAP theorem, perspectives of key folks in blockchain space • Consensus algorithms • Hyperledger • Blockchain applications • Hyperledger internships 3
  • 4. “We have proposed a system for electronic transactions without relying on trust.” 4
  • 5. “We have proposed a system for electronic transactions without relying on trust.”* * https://bitcoin.org/bitcoin.pdf Not true – says Bruce Schneier – Hyperledger Forum, December 2018 5
  • 6. What is trust? (1/2) Reference: Bruce Schneier’s example from Hyperledger Forum 2018 My building lobby (1) (2) (3) (4) 6
  • 7. What is trust? (2/2) • Can trust ever be eliminated? • Trust is not eliminated. It is shifted. • In the case of Bitcoin, the trust shifts from Governments and Banks to a piece of software. 7
  • 8. Bitcoin “paper” – Conclusion We have proposed a system for electronic transactions without relying on trust. We started with the usual framework of coins made from digital signatures, which provides strong control of ownership, but is incomplete without a way to prevent double-spending. To solve this, we proposed a peer-to-peer network using proof- of-work to record a public history of transactions that quickly becomes computationally impractical for an attacker to change if honest nodes control a majority of CPU power. The network is robust in its unstructured simplicity. Nodes work all at once with little coordination. They do not need to be identified, since messages are not routed to any particular place and only need to be delivered on a best effort basis. Nodes can leave and rejoin the network at will, accepting the proof-of-work chain as proof of what happened while they were gone. They vote with their CPU power, expressing their acceptance of valid blocks by working on extending them and rejecting invalid blocks by refusing to work on them. Any needed rules and incentives can be enforced with this consensus mechanism. https://bitcoin.org/bitcoin.pdf 8
  • 9. Bitcoin “paper” – Conclusion We have proposed a system for electronic transactions without relying on trust. We started with the usual framework of coins made from digital signatures, which provides strong control of ownership, but is incomplete without a way to prevent double-spending. To solve this, we proposed a peer-to-peer network using proof- of-work to record a public history of transactions that quickly becomes computationally impractical for an attacker to change if honest nodes control a majority of CPU power. The network is robust in its unstructured simplicity. Nodes work all at once with little coordination. They do not need to be identified, since messages are not routed to any particular place and only need to be delivered on a best effort basis. Nodes can leave and rejoin the network at will, accepting the proof-of-work chain as proof of what happened while they were gone. They vote with their CPU power, expressing their acceptance of valid blocks by working on extending them and rejecting invalid blocks by refusing to work on them. Any needed rules and incentives can be enforced with this consensus mechanism. https://bitcoin.org/bitcoin.pdf So, no non-electronic (aka paper) transactions? enuf said. do not pay more than once really? what is work? for ever? distributed? anonymity is a goal ? churn consensus algorithm is fixed. interesting the core … 9
  • 10. The origins of the word blockchain… Ehrsam, Meyer, Smith and Tuchman - Cipher Block Chaining (CBC) mode of operation - 1976 https://patents.google.com/patent/US4074066A/en https://satoshi.nakamotoinstitute.org/emails/cryptography/6/ Hal Finney – “block chain” – two letter word. 2008-11-09 01:58:48 UTC Earliest… As recently understood… (approx.) 10
  • 11. The emergence of “standard” definitions to buzz word terms… • What is a standard definition? • A definition created by a standards body such as National Institute of Standards and Technology (NIST) – US, or ISO. The definition is typically first published as a draft version for feedback from public at large or a select group. • Cloud Computing • Utility Computing (McCarthy – 1961), Cloud computing (1996, Compaq Business plan per MIT TR), AWS 2006 • NIST.SP.800-145 - November 2009 (first draft), October 2011 (published). • https://www.nist.gov/news-events/news/2011/10/final-version-nist-cloud-computing-definition-published • ISO – ISO/IEC 17788:2014 • https://www.iso.org/standard/60544.html • Blockchain (~2008) • NIST.IR.8202 - Blockchain Technology Overview – January 2018 (first draft), October 2018 (published) • https://csrc.nist.gov/publications/detail/nistir/8202/final • ISO definition still in progress • https://www.iso.org/standard/73771.html?browse=tc 11
  • 12. What is blockchain? • NIST.IR.8202 • (first two lines of intro) Blockchains are tamper evident and tamper resistant digital ledgers implemented in a distributed fashion (i.e., without a central repository) and usually without a central authority (i.e., a bank, company, or government). At their basic level, they enable a community of users to record transactions in a shared ledger within that community, such that under normal operation of the blockchain network no transaction can be changed once published. What is a block? – grouping of transactions What is a transaction? – a state changing mechanism Does the definition clearly state append-only aspect of ledger? 12
  • 13. What is a “ledger”? • https://www.merriam-webster.com/dictionary/ledger • a book containing accounts to which debits and credits are posted from books of original entry • a horizontal board used for vertical support (as in scaffolding) • The ledger familiar to “most” of us…? • Personal journal 13
  • 14. Ledger vs. personal journal Ledger Personal journal Written on Paper with typically pen Paper, with pen or pencil Can also be written with IT system (e.g., computer, SaaS) IT system (e.g., computer, SaaS) Record of who made changes Important Not so much Common primary application Recording monetary transactions Thoughts Information lay out Structure (tabular), credit/debit, with dates Usually with dates Information is appended? Typically, yes Typically, yes Shared with others Employees (probably). Other entities, no, unless IRS J Depends J 14
  • 15. What is a digital ledger? • A ledger stored in a digital form • On a (personal) computer or a set of computers • Can contain data ranging from few bytes to peta bytes, and beyond • What is distributed paper ledger? • Create copies of paper and distribute it to relevant folks whenever there is a change? • What is a distributed digital ledger? (or simply distributed ledger) • Ledgers stored in digital form on a set of computers (e.g., cloud), where data repository is not confined to a single computer (NIST: without central repository). The structure of the information stored within the ledger depends on the application. 15
  • 16. Tamper evident and tamper resistant • Immutable: Merriam-Webster • https://www.merriam-webster.com/dictionary/immutable • not capable of or susceptible to change • Why do we write personal checks with a pen and not with a pencil? • May be, no one writes personal checks these days J • tamper evident and tamper resistant – to an extent • Can a (distributed) digital ledger be changed? • Of course! • How to detect changes to a (distributed) digital ledger and prevent changes? • Detect changes: audit logs • Prevent changes: authz, authn (requires identity) 16
  • 17. [Lack of] Central authority or central repository - Examples • I run a database on my single machine. • Central repository? • Central authority? • A big search engine has a massive farm of distributed machines connected over network, that work together to respond to search queries. • Central repository? • Central authority? • A music file-sharing system (Napster) has a central list of which users have files, but files are downloaded peer-to-peer. • Central authority? • Central repository? • A file-sharing network has a distributed index of files and file chunks. • Central repository? • Central authority? 17
  • 18. Lets look at Bitcoin again 1. Decentralized – without central authority? • Hash power concentration • https://www.blockchain.com/en/pools • Crypto exchange concentration • https://www.bbc.com/news/world-us- canada-47203706 2. Distributed? • Yeah 3. Anonymity? • Public key per transaction 4. Energy efficiency? • No 4. Non-crypto currency applications • Not easy 5. Storage capacity per node (~30 GB) • Ever increasing 6. Mining reward • Decreasing with time. 12.5 bitcoins today 7. Transaction fees • How a transaction ends up in a block • Increasing with time • Resistance to Sybil attacks • Sybil attack: Create ‘fake identities’ to take over portion of id space in a system • Resistance: Yes, proof of work 18
  • 19. Bitcoin: transaction types Input 0 from Alice, signed by Alice Output 0 “To Bob” Output 1 “To Alice” (change) Common transaction Alice pays Bob 1 2 Input 0 Output 0 Transaction aggregating funds Input 1 Input N 3 Transaction distributing funds Input 0 Output 0 Output 1 Output N Payment is to a “public key” 19 Output => UTXO: unspent transaction output
  • 20. Bitcoin: transactions are grouped into blocks Block N T1 T2: A -> B T3 T4 Block N+1 B->C Block N+2 C->D H(N) H(N+1) T1 T2 T3 T4 H() H() H() H() H() H() H(N) Mining: find a nonce such hash of merkle tree + nonce is less than target and takes on avg 10 minutes to compute Which transaction to include in block? Transaction fee higher than some minimum. [decentralized or distributed?] 20
  • 22. The design options in Blockchain • Scalability – as many nodes as possible • Performance – write to chain as quickly as possible • Anonymity (or conversely, strong identity) – not “easily traceable” back to entity • Privacy – keep transactions data and transaction occurrence confidential among involved parties • Often informed by: • Application-specific (crypto-currency) vs. agnostic • One network to rule them all vs. many networks • Environmental friendly (Bitcoin proof-of-work is energy inefficient) 22
  • 23. The design options in Blockchain – Scalability Triangle – Vitalik Buterin Assume the total computational/bandwidth capacity of a regular computer is O(c), and the total load of a blockchain is O(n) Decentralization: the system can run in an environment where all nodes have O(c) resources • Possible weakening: can have supernodes, but require only 1 of N supernodes to be honest Security: the system can survive attacks up to some specific percentage of all miners/validators (eg. 33%) Scalability: the system can handle a load of O(n) > O(c) • Computation • State storage • Bandwidth https://vitalik.ca/files/Ithaca201807_Sharding.pdf Scalability Security Decentralization Claim: we can reach the middle of the triangle, though we do need to use some more complex tools to get there (slide 6 of link below) 23
  • 24. The design options in Blockchain – Matt Corello – aka Bluematt - Bitcoin • Trustlessness • Scalability • Identity (or lack of it) http://diyhpl.us/wiki/transcripts/baltic-honeybadger/2018/trustlessness-scalability-and-directions-in-security-models/ 24
  • 25. The design options in Blockchain – Hyperledger architecture group white paper • Linux foundation project for creating open source permissioned blockchain networks https://www.hyperledger.org/wp-content/uploads/2017/08/Hyperledger_Arch_WG_Paper_1_Consensus.pdf Comparison of permissioned consensus approaches and standard proof of work 25
  • 26. What is Finality? • “Finality means that once a transaction is committed, it cannot be reversed, i.e. the data cannot be rolled back to the previous state. Different blockchain systems may provide different types of finality. Typically, this is defined in the consensus protocol. Different types of consensus exist, such as voting-based consensus with immediate finality and lottery-based consensus with probabilistic finality.” https://www.hyperledger.org/wp-content/uploads/2018/10/HL_Whitepaper_Metrics_PDF_V1.01.pdf 26
  • 27. The design options in Blockchain – CAP theorem equivalent for blockchain • Decentralization, consistency, scalability • http://msrg.org/publications/pdf_files/2018/bcbi-icdcs18- Towards_Dependable,_Scalable,_an.pdf 27
  • 28. What is CAP-theorem-equivalent for blockchain? • Which blockchain? • Which consensus algorithm? • Which model? • … Will be a nice contribution…. 28
  • 29. Consensus algorithms • Background • Crash-tolerant consensus • Byzantine consensus • Nakamoto consensus (aka proof of work) • Proof of stake • Proof of elapsed time https://hackernoon.com/a-hitchhikers-guide-to-consensus-algorithms-d81aae3eb0e3 Cachin, Vucolic - https://arxiv.org/pdf/1707.01873.pdf 29
  • 30. Consensus algorithms - Background • Lamport Byzantine generals problem [1982] • Schneider – task of reaching and maintaining consensus among nodes involves [1990]: • A (deterministic) state machine that implements the logic of the service to be replicated • A consensus protocol to disseminate requests among the nodes, such that each node executes the same sequence of requests on its instance of the service. • Traditionally in literature, consensus means reaching agreement on single request (first) – atomic broadcasts provide agreement on sequence of requests. Cachin, Vucolic - https://arxiv.org/pdf/1707.01873.pdf 30
  • 31. Crash-tolerant consensus • Survive node crashes • Progression in epochs or views with a unique leader for each view • Replace leader • N/2-1 failures • Paxos (Zoo-keeper), Raft (etcd) 31
  • 32. Byzantine consensus • Practical Byzantine Fault Tolerance (PBFT) • < n/3 (note the inequality) nodes can be malicious (or system must have 3k+1 nodes for k nodes to be malicious) • Commercial implementations hard to find 32
  • 33. Nakamoto consensus aka proof of work • (Nodes) vote with their CPU power, expressing their acceptance of valid blocks by working on extending them and rejecting invalid blocks by refusing to work on them. Any needed rules and incentives can be enforced with this consensus mechanism. 33
  • 34. Proof of stake • Miners stake their tokens on which blocks are valid • Miners spend their tokens on which fork to support • If most people vote on the correct fork, miners who work on the wrong fork can loose their stake 34
  • 35. Distributed Ledger Technologies aka Blockchain categorization Drive value of cryptocurrency Cryptocurrency for a business use-case Blockchain for business Anonymous Permissioned CryptocurrencyNon-Cryptocurrency Standards bodies and consortiums 35
  • 36. Blockchain types • Public blockchain • Ledger is public, anyone can join? • Private blockchain • Ledger is private, anyone can join? • Permissioned blockchain • Ledger can be public or private, join requires consent of existing parties 36
  • 37. What is Hyperledger? • Hyperledger is an open source collaborative effort created to advance cross-industry blockchain technologies. It is a global collaboration, hosted by The Linux Foundation, including leaders in finance, banking, Internet of Things, supply chains, manufacturing and Technology. • Launched in February 2016 https://www.hyperledger.org/about Frameworks Tools Hyperledger Indy Hyperledger Fabric Hyperledger Iroha Hyperledger Sawtooth Hyperledger Burrow Hyperledger Composer Hyperledger Explorer Hyperledger Cello 37
  • 38. Hyperledger Projects Design Philosophy • Consensus Layer • Responsible for generating an agreement on the order and confirming the correctness of the set of transactions that constitute a block • Smart Contract Layer • Responsible for processing transaction requests and determining if transactions are valid by executing business logic. • Communication Layer • Responsible for peer-to-peer message transport between the nodes that participate in a shared ledger instance • Data Store Abstraction (Ledger) • Allows different data-stores to be used by other modules. • Crypto Abstraction • Allows different crypto algorithms or modules to be swapped out without affecting other modules. • Identity Services • Enables the establishment of a root of trust during setup of a blockchain instance, the enrollment and registration of identities or system entities during network operation, and the management of changes like drops, adds, and revocations. Also, provides authentication and authorization. • Policy Services • Responsible for policy management of various policies specified in the system, such as the endorsement policy, consensus policy, or group management policy. It interfaces and depends on other modules to enforce the various policies. • APIs • Enables clients and applications to interface to blockchains. • Interoperation • Supports the interoperation between different blockchain instances 38
  • 39. Hyperledger Fabric releases • https://github.com/hyperledger/fabric#releases 39
  • 40. Overview of Hyperledger Fabric – Key Design Goals • The four P’s • Permissioned • Privacy • Pluggability • Performance 40
  • 41. Permissioned: Existing members determine who can join the network, and update configuration Public blockchains • Download software and connect to network • Configuration updated through developer or community consensus Hyperledger Fabric • Policy-based mechanism to admit new members and to update configuration 6/8 votes (admit A: majority vote) A A B I want to invite A to network A B A B A B A B A B A B A B B I want to invite B to network A B 3/8 votes (reject B: majority vote) Permissioned != Private 41
  • 42. Privacy: Smart contract execution, and transaction data storage limited to a set of nodes in the network based on policy Public blockchains • Every node runs smart contract • Every full node can potentially have a full copy of the ledger Hyperledger Fabric • A subset of nodes will run smart contracts • The ledger updates are limited to set of nodes (channel). • Nodes in a channel can directly share private data with subset of nodes (collections, v1.1 feature) SC SC SC SC SC SC SC SC SCSC SC Channel / Private data collection 42
  • 43. Pluggability: consensus, identity provider, crypto, data format, smart contract language Public blockchains • Fixed or hard to change consensus algorithm (proof of work) • Fixed encryption (e.g., secp256k1) • Identity = public key - self • Domain specific language (DSL) for writing smart contracts Hyperledger Fabric • Pluggable consensus algorithm (PBFT, Kafka) • Pluggable crypto service provider • Pluggable identity provider, zero knowledge proofs • General data format, key / value pair • General purpose languages for writing smart contracts (Javascript, Go) 43
  • 44. Performance: transactions should commit quickly Public blockchains • Use proof of work / proof-of-stake as consensus algorithm due to which it may be a while before transactions are final (e.g., 60 minutes) • Transaction commitments are often probabilistic Hyperledger Fabric • Uses a voting based consensus mechanism • Transaction commitments are immediately final 44
  • 45. Ok, so where is mining in Hyperledger Fabric? • There is no mining – however, the consensus algorithm is pluggable • Consensus properties: safety, liveness • The Kafka service used in Hyperledger Fabric is crash tolerant, but not Byzantine fault tolerant source: https://www.hyperledger.org/wp-content/uploads/2017/08/Hyperledger_Arch_WG_Paper_1_Consensus.pdf Hyperledger Fabric Hyperledger Sawtooth 45
  • 46. Hyperledger Fabric and Ethereum* – A summary Hyperledger Fabric Ethereum Open source Yes Yes Live network No – create your own network Yes Who can join the network? Depends on the rules created by network creators – default majority vote (Permissioned) Anyone Smart contract language Javascript, Go Smart contracts called chaincode in Fabric Solidity, Vyper, LLL Rogue smart contract prevention Explicit review and installation of smart code before execution (no notion of gas) Gas Who executes smart contracts? Subset of nodes (or all) All nodes by default / channels Who stores the blocks? (state visibility) Subset of nodes (or all) All nodes by default / channels Consensus algorithm Execute-order-validate (voting) – no mining PoW, PoS Identity X.509 certificate issued by membership service provider of a peer. Contains public key Public key Incentive for running a node Business network Ether *comparing apples to oranges? (open source software vs live public network) 46
  • 47. Blockchain Applications • Cryptocurrency (enuf said) • Food Safety (provenance of goods from source to destination) • The physical to digital correlation problem… • Vitalik’s view on Blockchain applications (Dec 2018) tweet • 50 examples of blockchain real world use cases • Self-“Sovereign” Identity 47
  • 48. Food Safety Seller Crop / Quantity Buyer Joe (farmer) sold crops (SKU#j1) Mangoes / 100 lbs Alice Alice (distributor) sold crops (SKU#j1) Mangoes / 10 lbs Walmart Alice (distributor) sold crops (SKU#j1) Mangoes / 90 lbs Kroger Tina (farmer) sold crops (SKU#t1) Mangoes / 200 lbs Walmart ‘Joe’ the farmer ‘Alice’ the distributor “Tina” the farmer Seller Crop/Quantity Buye r Joe(farmer)soldcrops(SKU#j1) Mangoes/100lbs Alice Alice(distributor)soldcrops(SKU#j1) Mangoes/10lbs Wal mar t Alice(distributor)soldcrops(SKU#j1) Mangoes/90lbs Krog er Tina(farmer)soldcrops(SKU#t1) Mangoes/200lbs Wal mar t Seller Crop/Quantity Buye r Joe(farmer)soldcrops(SKU#j1) Mangoes/100lbs Alice Alice(distributor)soldcrops(SKU#j1) Mangoes/10lbs Wal mar t Alice(distributor)soldcrops(SKU#j1) Mangoes/90lbs Krog er Tina(farmer)soldcrops(SKU#t1) Mangoes/200lbs Wal mar t Seller Crop/Quantity Buye r Joe(farmer)soldcrops(SKU#j1) Mangoes/100lbs Alice Alice(distributor)soldcrops(SKU#j1) Mangoes/10lbs Wal mar t Alice(distributor)soldcrops(SKU#j1) Mangoes/90lbs Krog er Tina(farmer)soldcrops(SKU#t1) Mangoes/200lbs Wal mar t Seller Crop/Quantity Buye r Joe(farmer)soldcrops(SKU#j1) Mangoes/100lbs Alice Alice(distributor)soldcrops(SKU#j1) Mangoes/10lbs Wal mar t Alice(distributor)soldcrops(SKU#j1) Mangoes/90lbs Krog er Tina(farmer)soldcrops(SKU#t1) Mangoes/200lbs Wal mar t Seller Crop/Quantity Buye r Joe(farmer)soldcrops(SKU#j1) Mangoes/100lbs Alice Alice(distributor)soldcrops(SKU#j1) Mangoes/10lbs Wal mar t Alice(distributor)soldcrops(SKU#j1) Mangoes/90lbs Krog er Tina(farmer)soldcrops(SKU#t1) Mangoes/200lbs Wal mar t Block N Block N+1 Block N+2 Block N+3 48
  • 49. Vitalik’s view on blockchain applications • https://twitter.com/VitalikButerin/status/1072162014498148355 49
  • 50. 50+ examples of blockchains in real world https://medium.com/@matteozago/50-examples-of-how-blockchains-are-taking-over-the-world-4276bf488a4b 50
  • 51. Self-sovereign identity (SSI) • What is SSI? (def. by Christopher Allen) • http://www.lifewithalacrity.com/2016/04/the-path-to-self-soverereign-identity.html • The principles • Existence. Users must have an independent existence. • Control. Users must control their identities. • Access. Users must have access to their own data. • Transparency. Systems and algorithms must be transparent. • Persistence. Identities must be long-lived. • Portability. Information and services about identity must be transportable. • Interoperability. Identities should be as widely usable as possible. • Consent. Users must agree to the use of their identity. • Minimalization. Disclosure of claims must be minimized. • Protection. The rights of users must be protected. • Decentralized identity foundation (https://identity.foundation/) • Sovrin foundation (https://sovrin.org/) – Columbia can be a steward node (https://sovrin.org/stewards/) 51