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www.csiro.au
Blockchain: Background and
Data61 Research Overview
Ingo Weber | Principal Research Scientist & Team Leader
ingo.weber@data61.csiro.au
Conj. Assoc. Professor, UNSW Australia | Adj. Assoc. Professor, Swinburne University
Blockchain Research at Data61
Blockchain Research at Data61
• Designing Systems
with Blockchain
– Design Trade-offs
– Model-driven
development
– Governance and risk
management
• Trustworthy
Blockchain Systems
– Formal
– Empirical
Blockchain | Data61, CSIRO3 |
• Defining and Using
Smart Contracts
– As Legal Contracts
– Business Process
Projects with Australian Treasury
• DLT Foresight
– What might plausibly happen,
across society & economy?
• Technical Risks & Opportunities
– How do needs in various use cases
fit blockchain’s capabilities?
Blockchain | Data61, CSIRO4 |
• Funded by Australian National Innovation Science Agenda
• Two reports, launched 6 June 2017
• See www.data61.csiro.au/blockchain
Designing Systems with Blockchain
Data61 : Preliminary Findings on Blockchain/DLT Projects5 |
• Design Process
• A taxonomy of blockchain-based systems for architecture design, X. Xu, I. Weber, M.
Staples et al., ICSA2017.
• The blockchain as a software connector, X. Xu, C. Pautasso, L. Zhu et al., WICSA2016.
• Quality Analysis
• Comparing blockchain and cloud services for business process execution, P. Rimba, A.
B. Tran, I. Weber et al., ICSA2017.
• Predicting latency of blockchain-based systems using architectural modelling and
simulation, R. Yasaweerasinghelage, M. Staples and I. Weber, ICSA2017.
• Model-Driven
• Regerator: a Registry Generator for Blockchain, A. B. Tran, X. Xu, I. Weber, CAISE2017.
• From business process models, see next slide
• Integration with other systems
• EthDrive: A Peer-to-Peer Data Storage with Provenance, X. L. Yu, X. Xu, B. Liu, CAISE2017.
• Governance and risk management
• Risks and Opportunities for Systems Using Blockchain and Smart Contracts, Treasury
report
Defining and Using Smart Contracts
Data61 : Preliminary Findings on Blockchain/DLT Projects6 |
• Business Process
• Untrusted business process monitoring and execution
using blockchain,
I. Weber, X. Xu, R. Riveret et al., BPM2016
• Optimized Execution of Business Processes on
Blockchain,
L. García-Bañuelos, A. Ponomarev, M. Dumas, Ingo
Weber, BPM2017
• Caterpillar: A blockchain-based business process
management system,
O. López-Pintado, L. García-Bañuelos, M. Dumas, and I.
Weber, BPM2017 Demo
• Runtime verification for business processes utilizing
the Bitcoin blockchain,
C. Prybila, S. Schulte, C. Hochreiner, and I. Weber,
Future Generation Computer Systems (FGCS), accepted
August 2017
• Legal vs. Smart Contracts
• Evaluation of Logic-Based Smart Contracts for
Blockchain Systems,
F. Idelberg, G. Governatori, R. Riveret et al., RuleML2016
Trustworthy Blockchain Systems
Data61 : Preliminary Findings on Blockchain/DLT Projects7 |
• Formal
• The Blockchain Anomaly, C. Natoli, V. Gramoli, NCA2016
• On the Danger of Private Blockchains, V. Gramoli, DCCL2016
• (Leader/Randomization/Signature)-free Byzantine Consensus for Consortium
Blockchains, T. Crain, V. Gramoli, M. Larrea, M. Raynal, arXiv:1702.03068, 2016
• Empirical
• On availability for blockchain-
based systems, I. Weber, V.
Gramoli et al., SRDS 2017
• New kids on the block: an
analysis of modern blockchains,
L. Anderson, R. Holz, A.
Ponomarev et al.,
arXiv:1606:06530, 2016
Demonstration
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber8 |
Red Belly Blockchain (with USyd)
• New technology particularly for private / consortium blockchain
• In lab experiment achieved 400,000 tps with 100 nodes and
660,000 tps with 300 nodes
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber9 |
Architecting Applications on Blockchain
A taxonomy of blockchain-based systems for architecture design, X. Xu, I. Weber, M. Staples et al., ICSA2017.
Comparing blockchain and cloud services for business process execution, P. Rimba, A. B. Tran, I. Weber et al.,
ICSA2017, short paper.
Predicting latency of blockchain-based systems using architectural modelling and simulation, R.
Yasaweerasinghelage, M. Staples and I. Weber, ICSA2017, short paper.
On availability for blockchain-based systems, I. Weber, V. Gramoli et al., SRDS 2017
Overview
• Many interesting applications for Blockchain
• Basically of interest in most lack-of-trust settings where a distributed
application can coordinate multiple parties
• Examples:
– Supply chains
– Handling of titles, e.g., land, water, vehicles
– Identity
• Many startups and initiatives from enterprises / governments
• ... but also many challenges
• When to use blockchain
• Trade-offs in architecture
– Downsides: cost, latency, confidentiality
– What to handle on-chain, what off-chain?
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber11 |
Our work – AAP team
• Architecting applications on Blockchain:
• Taxonomy and design process
• “Cost of Distrust”: how much more expensive is blockchain?
• Availability analysis from viewpoint of DApss
• Latency: simulation under changes
• Model-driven development of smart contracts
• Business process execution
• Model-based generation of registries and UIs
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber12 |
Blockchains are Not Stand-Alone Systems
Data61 : Preliminary Findings on Blockchain/DLT Projects13 |
UI for humans
IoT
integration
Auxiliary
databases
Legacy
systems
Key
management
private
data
BIG DATA
Blockchain is a component
Non-Functional Trade-Offs
• Compared to conventional database & script engines,
blockchains have:
(-) Confidentiality, Privacy
(+) Integrity, Non-repudiation
(+ read/ ? write) Availability
(-) Modifiability
(-) Throughput / Scalability / Big Data
(+ read/ - write) Latency
Data61 : Preliminary Findings on Blockchain/DLT Projects14 |
Security: combination of
CIA properties
Design process
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber15 |
Taxonomy
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber16 |
Blockchain-related design decisions regarding (de)centralisation, with an indication of
their relative impact on quality properties
Legend: ⊕: Less favourable, ⊕⊕: Neutral, ⊕⊕⊕: More favourable
Taxonomy
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber17 |
Blockchain-related design decisions regarding storage and computation, with an
indication of their relative impact on quality properties
Taxonomy
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber18 |
Blockchain-related design decisions regarding blockchain configuration
Cost of Distrust
• RQ: How much more expensive is blockchain over Cloud services?
• Lens: business process execution
• AWS SWF vs. Ethereum public blockchain
– In both cases: pay per instruction
• Experiments on two use cases:
– Incident management (literature)
– 32 instances on public Ethereum vs. 1000 runs on SWF
– Invoicing (industry, 5316 log traces, 65K events)
– Full log replayed on SWF and private Ethereum
• Result:
• 2 orders of magnitude more expensive to use blockchain
– exchange rate: 1 Ether = US$ 11.32 (26/8/2016)
• ~US$ 0.35 per process instance on public blockchain
– outweighed by cost of escrow (if needed) for about US$ 10 of value
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber19 |
Availability
• Availability: the system‘s readiness for correct service
• Blockchain as component: read: +++ ; write: ?
• Ethereum: 12 blocks confirmation is accepted, said to take 3 mins
• Measurements:
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber20 |
Availability
• Potential issue: block gas limit
• Gas limit is set by miners through “voting”
• The sum of Gas of all transactions in a block must be less than the limit
• Response to DDoS attack: lower block gas limit
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber21 |
Availability
• Potential issue: block gas limit
• Gas limit is set by miners through “voting”
• The sum of Gas of all transactions in a block must be less than the limit
• Response to DDoS attack: lower block gas limit
• Who would be affected by that?
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber22 |
Latency simulation
• Goal: predict latency for blockchain-based application before
building it
• Challenge specifically for latency: mean and variation
• Means: Architecture performance modeling
• Paladio Component Models with individual latency distributions +
connections + probability of branching
• Allows changing the models for What-If analysis
• For instance: change inter-block time on private blockchain – what does that
mean for overall application latency?
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber23 |
Latency simulation
• Goal: predict latency for blockchain-based application before
building it
• Challenge specifically for latency: mean and variation
• Means: Architecture performance modeling
• Paladio Component Models with individual latency distributions +
connections + probability of branching
• Allows changing the models for What-If analysis
• For instance: change inter-block time on private blockchain – what does that
mean for overall application latency?
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber24 |
Latency: what if we change required
number of confirmation blocks?
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber
25 |
1 block 6 blocks
12 blocks
Using Smart Contracts for Business
Process Monitoring and Execution
Ingo Weber, Sherry Xu, Regis Riveret, Guido Governatori, Alexander Ponomarev and Jan Mendling
Untrusted business process monitoring and execution using blockchain. BPM 2016
Luciano García-Bañuelos, Alexander Ponomarev, Marlon Dumas, and Ingo Weber
Optimized Execution of Business Processes on Blockchain. BPM 2017
Orlenys López-Pintado, Luciano García-Bañuelos, Marlon Dumas, and Ingo Weber.
Caterpillar: A blockchain-based business process management system. BPM Demo 2017
Motivation
• Integration of business processes across organizations:
a key driver of productivity gains.
• Collaborative process execution
• Doable when there is trust – supply chains can be tightly
integrated
• Problematic when involved organizations have a lack of trust in
each other
 if 3+ parties should collaborate, where to execute the process
that ties them together?
• Common situation in “coopetition”
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber27 |
Motivation: example
Issues:
- Knowing the status, tracking correct execution
- Handling payments
- Resolving conflicts
 Trusted 3rd party ?
 Blockchain!
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber28 |
Approach in a nutshell
• Goal: execute collaborative business processes as smart
contracts
• Translate (enriched) BPMN to smart contract code
• Triggers act as bridge between Enterprise world and blockchain
• Smart contract does:
– Independent, global process monitoring
– Conformance checking: only expected messages are accepted,
only from the respective role
– Automatic payments & escrow
– Data transformation
– Encryption
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber29 |
Architecture
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber30 |
Runtime
• Instantiation:
• New instance contract per process instance
• Assign accounts to roles during initialization
• Exchange keys and create secret key for the instance
• Messaging:
• Instead of sending direct WS calls: send through triggers & smart contract
• Instance contract handles:
– Global monitoring
– Conformance checking
– Automated payments*
– Data transformation*
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber31 |
Bulk Buyer BB Trigger
Smart
Contract
Manufact-
urer
Mf. Trigger
API call:
Order goods
Blockchain
Transaction
(BCTX)
Smart Contract effect
Check
conformance
API call
MiddlemanMm. Trigger
API call:
Place order
Execute
internal logic
BCTX
Smart Contract effect
Check
conformance
API call
Demonstration
Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber32 |
Summary
• Architecting and developing applications on Blockchain is challenging
• Our research:
– Designing applications with Blockchain
– Software Architecture methods for Blockchain-based applications
– Empirical and formal research on Blockchains
– How to use smart contracts
– Model-driven development of smart contracts
• Using Blockchain for process monitoring and execution
• Applicable in lack-of-trust settings for collaborative process execution
• Our approach:
– translate from process models to Solidity
– use triggers to connect Blockchain and Enterprise systems
• Evaluation results: latency and cost should be acceptable in many cases
• Screencast video and more details – see papers
www.csiro.au
Thank you
Ingo Weber | Principal Research Scientist & Team Leader
ingo.weber@data61.csiro.au
My publications: http://imweber.de/publications.html
AAP team Blockchain research: https://research.csiro.au/data61/blockchain/
Blockchain reports: https://www.data61.csiro.au/blockchain/
References
1. On availability for blockchain-based systems, Ingo Weber, Vincent Gramoli, Mark Staples, Alex Ponomarev,
Ralph Holz, An Binh Tran, and Paul Rimba. In SRDS’17: IEEE International Symposium on Reliable Distributed
Systems, Hong Kong, China, September 2017.
2. Optimized execution of business processes on blockchain, Luciano García-Bañuelos, Alexander Ponomarev,
Marlon Dumas, and Ingo Weber. 15th International Conference on Business Process Management (BPM’17),
Barcelona, Spain, September 2017.
3. Orlenys López-Pintado, Luciano García-Bañuelos, Marlon Dumas, and Ingo Weber. Caterpillar: A blockchain-
based business process management system. In BPM'17: International Conference on Business Process
Management, Demo track, Barcelona, Spain, September 2017.
4. Runtime verification for business processes utilizing the Bitcoin blockchain, C. Prybila, S. Schulte, C. Hochreiner,
and I. Weber, Future Generation Computer Systems (FGCS), accepted August 2017
5. Risks and opportunities for systems using blockchain and smart contracts, Mark Staples, Shiping Chen, Sara
Falamaki, Alex Ponomarev, Paul Rimba, An Binh Tran, Ingo Weber, Xiwei Xu, and Zhenjiang Zhu. Technical
report, Data61, CSIRO, Sydney, Australia, June 2017.
6. Regerator: a Registry Generator for Blockchain, An Binh Tran, Xiwei Xu, Ingo Weber, Mark Staples and Paul
Rimba. 29th International Conference on Advanced Information Systems Engineering (CAISE’17).
7. EthDrive: A Peer-to-Peer Data Storage with Provenance, Xiao Liang Yu, Xiwei Xu and Bin Liu. 29th International
Conference on Advanced Information Systems Engineering (CAISE’17).
8. The Balance Attack or Why Forkable Blockchains are Ill-Suited for Consortium, Christopher Natoli and Vincent
Gramoli. 2017 IEEE/IFIP International Conference on Dependable Systems and Networks (DSN’17).
References
9. Blockchain Consensus, Tyler Crain, Vincent Gramoli, Michel Raynal, Mikel Larrea. Proceedings of AlgoTel 2017.
10. A taxonomy of blockchain-based systems for architecture design, Xiwei Xu, Ingo Weber, Mark Staples, Liming Zhu, Jan Bosch, Len
Bass, Cesare Pautasso and Paul Rimba. 2017 IEEE International Conference on Software Architecture (ICSA’17), Gothenburg,
Sweden, April 2017.
11. Comparing blockchain and cloud services for business process execution, Paul Rimba, An Binh Tran, Ingo Weber, Mark Staples,
Alexander Ponomarev and Xiwei Xu. Short paper, 2017 IEEE International Conference on Software Architecture (ICSA’17),
Gothenburg, Sweden, April 2017.
12. Predicting latency of blockchain-based systems using architectural modelling and simulation, Rajitha Yasaweerasinghelage, Mark
Staples and Ingo Weber. Short paper, 2017 IEEE International Conference on Software Architecture (ICSA’17), Gothenburg,
Sweden, April 2017.
13. The Blockchain Anomaly, Christopher Natoli, Vincent Gramoli. Proceedings of the 15th IEEE International Symposium on Network
Computing and Applications (NCA’16), IEEE Oct 2016
14. Evaluation of Logic-Based Smart Contracts for Blockchain Systems, Idelberg, Florian and Governatori, Guido and Riveret, Regis
and Sartor, Giovanni. 10th International Web Rule Symposium, July, 2016
15. New kids on the block: an analysis of modern blockchains, Luke Anderson, Ralph Holz, Alexander Ponomarev, Paul Rimba, Ingo
Weber. arXiv:1606:06530, 2016
16. On the Danger of Private Blockchains, Vincent Gramoli. Workshop on Distributed Cryptocurrencies and Consensus Ledgers
(DCCL’16), 2016
17. Untrusted business process monitoring and execution using blockchain, Ingo Weber, Sherry Xu, Regis Riveret, Guido Governatori,
Alexander Ponomarev and Jan Mendling. BPM 2016, Rio de Janeiro, Brazil , September, 2016
18. The blockchain as a software connector, Sherry Xu, Cesare Pautasso, Liming Zhu, Vincent Gramoli, Alexander Ponomarev, An Binh
Tran and Shiping Chen. WICSA2016, Venice, Italy, April, 2016

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Blockchain: Background and Data61 Research Overview

  • 1. www.csiro.au Blockchain: Background and Data61 Research Overview Ingo Weber | Principal Research Scientist & Team Leader ingo.weber@data61.csiro.au Conj. Assoc. Professor, UNSW Australia | Adj. Assoc. Professor, Swinburne University
  • 3. Blockchain Research at Data61 • Designing Systems with Blockchain – Design Trade-offs – Model-driven development – Governance and risk management • Trustworthy Blockchain Systems – Formal – Empirical Blockchain | Data61, CSIRO3 | • Defining and Using Smart Contracts – As Legal Contracts – Business Process
  • 4. Projects with Australian Treasury • DLT Foresight – What might plausibly happen, across society & economy? • Technical Risks & Opportunities – How do needs in various use cases fit blockchain’s capabilities? Blockchain | Data61, CSIRO4 | • Funded by Australian National Innovation Science Agenda • Two reports, launched 6 June 2017 • See www.data61.csiro.au/blockchain
  • 5. Designing Systems with Blockchain Data61 : Preliminary Findings on Blockchain/DLT Projects5 | • Design Process • A taxonomy of blockchain-based systems for architecture design, X. Xu, I. Weber, M. Staples et al., ICSA2017. • The blockchain as a software connector, X. Xu, C. Pautasso, L. Zhu et al., WICSA2016. • Quality Analysis • Comparing blockchain and cloud services for business process execution, P. Rimba, A. B. Tran, I. Weber et al., ICSA2017. • Predicting latency of blockchain-based systems using architectural modelling and simulation, R. Yasaweerasinghelage, M. Staples and I. Weber, ICSA2017. • Model-Driven • Regerator: a Registry Generator for Blockchain, A. B. Tran, X. Xu, I. Weber, CAISE2017. • From business process models, see next slide • Integration with other systems • EthDrive: A Peer-to-Peer Data Storage with Provenance, X. L. Yu, X. Xu, B. Liu, CAISE2017. • Governance and risk management • Risks and Opportunities for Systems Using Blockchain and Smart Contracts, Treasury report
  • 6. Defining and Using Smart Contracts Data61 : Preliminary Findings on Blockchain/DLT Projects6 | • Business Process • Untrusted business process monitoring and execution using blockchain, I. Weber, X. Xu, R. Riveret et al., BPM2016 • Optimized Execution of Business Processes on Blockchain, L. García-Bañuelos, A. Ponomarev, M. Dumas, Ingo Weber, BPM2017 • Caterpillar: A blockchain-based business process management system, O. López-Pintado, L. García-Bañuelos, M. Dumas, and I. Weber, BPM2017 Demo • Runtime verification for business processes utilizing the Bitcoin blockchain, C. Prybila, S. Schulte, C. Hochreiner, and I. Weber, Future Generation Computer Systems (FGCS), accepted August 2017 • Legal vs. Smart Contracts • Evaluation of Logic-Based Smart Contracts for Blockchain Systems, F. Idelberg, G. Governatori, R. Riveret et al., RuleML2016
  • 7. Trustworthy Blockchain Systems Data61 : Preliminary Findings on Blockchain/DLT Projects7 | • Formal • The Blockchain Anomaly, C. Natoli, V. Gramoli, NCA2016 • On the Danger of Private Blockchains, V. Gramoli, DCCL2016 • (Leader/Randomization/Signature)-free Byzantine Consensus for Consortium Blockchains, T. Crain, V. Gramoli, M. Larrea, M. Raynal, arXiv:1702.03068, 2016 • Empirical • On availability for blockchain- based systems, I. Weber, V. Gramoli et al., SRDS 2017 • New kids on the block: an analysis of modern blockchains, L. Anderson, R. Holz, A. Ponomarev et al., arXiv:1606:06530, 2016
  • 8. Demonstration Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber8 |
  • 9. Red Belly Blockchain (with USyd) • New technology particularly for private / consortium blockchain • In lab experiment achieved 400,000 tps with 100 nodes and 660,000 tps with 300 nodes Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber9 |
  • 10. Architecting Applications on Blockchain A taxonomy of blockchain-based systems for architecture design, X. Xu, I. Weber, M. Staples et al., ICSA2017. Comparing blockchain and cloud services for business process execution, P. Rimba, A. B. Tran, I. Weber et al., ICSA2017, short paper. Predicting latency of blockchain-based systems using architectural modelling and simulation, R. Yasaweerasinghelage, M. Staples and I. Weber, ICSA2017, short paper. On availability for blockchain-based systems, I. Weber, V. Gramoli et al., SRDS 2017
  • 11. Overview • Many interesting applications for Blockchain • Basically of interest in most lack-of-trust settings where a distributed application can coordinate multiple parties • Examples: – Supply chains – Handling of titles, e.g., land, water, vehicles – Identity • Many startups and initiatives from enterprises / governments • ... but also many challenges • When to use blockchain • Trade-offs in architecture – Downsides: cost, latency, confidentiality – What to handle on-chain, what off-chain? Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber11 |
  • 12. Our work – AAP team • Architecting applications on Blockchain: • Taxonomy and design process • “Cost of Distrust”: how much more expensive is blockchain? • Availability analysis from viewpoint of DApss • Latency: simulation under changes • Model-driven development of smart contracts • Business process execution • Model-based generation of registries and UIs Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber12 |
  • 13. Blockchains are Not Stand-Alone Systems Data61 : Preliminary Findings on Blockchain/DLT Projects13 | UI for humans IoT integration Auxiliary databases Legacy systems Key management private data BIG DATA Blockchain is a component
  • 14. Non-Functional Trade-Offs • Compared to conventional database & script engines, blockchains have: (-) Confidentiality, Privacy (+) Integrity, Non-repudiation (+ read/ ? write) Availability (-) Modifiability (-) Throughput / Scalability / Big Data (+ read/ - write) Latency Data61 : Preliminary Findings on Blockchain/DLT Projects14 | Security: combination of CIA properties
  • 15. Design process Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber15 |
  • 16. Taxonomy Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber16 | Blockchain-related design decisions regarding (de)centralisation, with an indication of their relative impact on quality properties Legend: ⊕: Less favourable, ⊕⊕: Neutral, ⊕⊕⊕: More favourable
  • 17. Taxonomy Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber17 | Blockchain-related design decisions regarding storage and computation, with an indication of their relative impact on quality properties
  • 18. Taxonomy Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber18 | Blockchain-related design decisions regarding blockchain configuration
  • 19. Cost of Distrust • RQ: How much more expensive is blockchain over Cloud services? • Lens: business process execution • AWS SWF vs. Ethereum public blockchain – In both cases: pay per instruction • Experiments on two use cases: – Incident management (literature) – 32 instances on public Ethereum vs. 1000 runs on SWF – Invoicing (industry, 5316 log traces, 65K events) – Full log replayed on SWF and private Ethereum • Result: • 2 orders of magnitude more expensive to use blockchain – exchange rate: 1 Ether = US$ 11.32 (26/8/2016) • ~US$ 0.35 per process instance on public blockchain – outweighed by cost of escrow (if needed) for about US$ 10 of value Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber19 |
  • 20. Availability • Availability: the system‘s readiness for correct service • Blockchain as component: read: +++ ; write: ? • Ethereum: 12 blocks confirmation is accepted, said to take 3 mins • Measurements: Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber20 |
  • 21. Availability • Potential issue: block gas limit • Gas limit is set by miners through “voting” • The sum of Gas of all transactions in a block must be less than the limit • Response to DDoS attack: lower block gas limit Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber21 |
  • 22. Availability • Potential issue: block gas limit • Gas limit is set by miners through “voting” • The sum of Gas of all transactions in a block must be less than the limit • Response to DDoS attack: lower block gas limit • Who would be affected by that? Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber22 |
  • 23. Latency simulation • Goal: predict latency for blockchain-based application before building it • Challenge specifically for latency: mean and variation • Means: Architecture performance modeling • Paladio Component Models with individual latency distributions + connections + probability of branching • Allows changing the models for What-If analysis • For instance: change inter-block time on private blockchain – what does that mean for overall application latency? Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber23 |
  • 24. Latency simulation • Goal: predict latency for blockchain-based application before building it • Challenge specifically for latency: mean and variation • Means: Architecture performance modeling • Paladio Component Models with individual latency distributions + connections + probability of branching • Allows changing the models for What-If analysis • For instance: change inter-block time on private blockchain – what does that mean for overall application latency? Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber24 |
  • 25. Latency: what if we change required number of confirmation blocks? Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber 25 | 1 block 6 blocks 12 blocks
  • 26. Using Smart Contracts for Business Process Monitoring and Execution Ingo Weber, Sherry Xu, Regis Riveret, Guido Governatori, Alexander Ponomarev and Jan Mendling Untrusted business process monitoring and execution using blockchain. BPM 2016 Luciano García-Bañuelos, Alexander Ponomarev, Marlon Dumas, and Ingo Weber Optimized Execution of Business Processes on Blockchain. BPM 2017 Orlenys López-Pintado, Luciano García-Bañuelos, Marlon Dumas, and Ingo Weber. Caterpillar: A blockchain-based business process management system. BPM Demo 2017
  • 27. Motivation • Integration of business processes across organizations: a key driver of productivity gains. • Collaborative process execution • Doable when there is trust – supply chains can be tightly integrated • Problematic when involved organizations have a lack of trust in each other  if 3+ parties should collaborate, where to execute the process that ties them together? • Common situation in “coopetition” Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber27 |
  • 28. Motivation: example Issues: - Knowing the status, tracking correct execution - Handling payments - Resolving conflicts  Trusted 3rd party ?  Blockchain! Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber28 |
  • 29. Approach in a nutshell • Goal: execute collaborative business processes as smart contracts • Translate (enriched) BPMN to smart contract code • Triggers act as bridge between Enterprise world and blockchain • Smart contract does: – Independent, global process monitoring – Conformance checking: only expected messages are accepted, only from the respective role – Automatic payments & escrow – Data transformation – Encryption Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber29 |
  • 30. Architecture Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber30 |
  • 31. Runtime • Instantiation: • New instance contract per process instance • Assign accounts to roles during initialization • Exchange keys and create secret key for the instance • Messaging: • Instead of sending direct WS calls: send through triggers & smart contract • Instance contract handles: – Global monitoring – Conformance checking – Automated payments* – Data transformation* Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber31 | Bulk Buyer BB Trigger Smart Contract Manufact- urer Mf. Trigger API call: Order goods Blockchain Transaction (BCTX) Smart Contract effect Check conformance API call MiddlemanMm. Trigger API call: Place order Execute internal logic BCTX Smart Contract effect Check conformance API call
  • 32. Demonstration Blockchain Smart Contracts: Use and Application in BPM | Ingo Weber32 |
  • 33. Summary • Architecting and developing applications on Blockchain is challenging • Our research: – Designing applications with Blockchain – Software Architecture methods for Blockchain-based applications – Empirical and formal research on Blockchains – How to use smart contracts – Model-driven development of smart contracts • Using Blockchain for process monitoring and execution • Applicable in lack-of-trust settings for collaborative process execution • Our approach: – translate from process models to Solidity – use triggers to connect Blockchain and Enterprise systems • Evaluation results: latency and cost should be acceptable in many cases • Screencast video and more details – see papers
  • 34. www.csiro.au Thank you Ingo Weber | Principal Research Scientist & Team Leader ingo.weber@data61.csiro.au My publications: http://imweber.de/publications.html AAP team Blockchain research: https://research.csiro.au/data61/blockchain/ Blockchain reports: https://www.data61.csiro.au/blockchain/
  • 35. References 1. On availability for blockchain-based systems, Ingo Weber, Vincent Gramoli, Mark Staples, Alex Ponomarev, Ralph Holz, An Binh Tran, and Paul Rimba. In SRDS’17: IEEE International Symposium on Reliable Distributed Systems, Hong Kong, China, September 2017. 2. Optimized execution of business processes on blockchain, Luciano García-Bañuelos, Alexander Ponomarev, Marlon Dumas, and Ingo Weber. 15th International Conference on Business Process Management (BPM’17), Barcelona, Spain, September 2017. 3. Orlenys López-Pintado, Luciano García-Bañuelos, Marlon Dumas, and Ingo Weber. Caterpillar: A blockchain- based business process management system. In BPM'17: International Conference on Business Process Management, Demo track, Barcelona, Spain, September 2017. 4. Runtime verification for business processes utilizing the Bitcoin blockchain, C. Prybila, S. Schulte, C. Hochreiner, and I. Weber, Future Generation Computer Systems (FGCS), accepted August 2017 5. Risks and opportunities for systems using blockchain and smart contracts, Mark Staples, Shiping Chen, Sara Falamaki, Alex Ponomarev, Paul Rimba, An Binh Tran, Ingo Weber, Xiwei Xu, and Zhenjiang Zhu. Technical report, Data61, CSIRO, Sydney, Australia, June 2017. 6. Regerator: a Registry Generator for Blockchain, An Binh Tran, Xiwei Xu, Ingo Weber, Mark Staples and Paul Rimba. 29th International Conference on Advanced Information Systems Engineering (CAISE’17). 7. EthDrive: A Peer-to-Peer Data Storage with Provenance, Xiao Liang Yu, Xiwei Xu and Bin Liu. 29th International Conference on Advanced Information Systems Engineering (CAISE’17). 8. The Balance Attack or Why Forkable Blockchains are Ill-Suited for Consortium, Christopher Natoli and Vincent Gramoli. 2017 IEEE/IFIP International Conference on Dependable Systems and Networks (DSN’17).
  • 36. References 9. Blockchain Consensus, Tyler Crain, Vincent Gramoli, Michel Raynal, Mikel Larrea. Proceedings of AlgoTel 2017. 10. A taxonomy of blockchain-based systems for architecture design, Xiwei Xu, Ingo Weber, Mark Staples, Liming Zhu, Jan Bosch, Len Bass, Cesare Pautasso and Paul Rimba. 2017 IEEE International Conference on Software Architecture (ICSA’17), Gothenburg, Sweden, April 2017. 11. Comparing blockchain and cloud services for business process execution, Paul Rimba, An Binh Tran, Ingo Weber, Mark Staples, Alexander Ponomarev and Xiwei Xu. Short paper, 2017 IEEE International Conference on Software Architecture (ICSA’17), Gothenburg, Sweden, April 2017. 12. Predicting latency of blockchain-based systems using architectural modelling and simulation, Rajitha Yasaweerasinghelage, Mark Staples and Ingo Weber. Short paper, 2017 IEEE International Conference on Software Architecture (ICSA’17), Gothenburg, Sweden, April 2017. 13. The Blockchain Anomaly, Christopher Natoli, Vincent Gramoli. Proceedings of the 15th IEEE International Symposium on Network Computing and Applications (NCA’16), IEEE Oct 2016 14. Evaluation of Logic-Based Smart Contracts for Blockchain Systems, Idelberg, Florian and Governatori, Guido and Riveret, Regis and Sartor, Giovanni. 10th International Web Rule Symposium, July, 2016 15. New kids on the block: an analysis of modern blockchains, Luke Anderson, Ralph Holz, Alexander Ponomarev, Paul Rimba, Ingo Weber. arXiv:1606:06530, 2016 16. On the Danger of Private Blockchains, Vincent Gramoli. Workshop on Distributed Cryptocurrencies and Consensus Ledgers (DCCL’16), 2016 17. Untrusted business process monitoring and execution using blockchain, Ingo Weber, Sherry Xu, Regis Riveret, Guido Governatori, Alexander Ponomarev and Jan Mendling. BPM 2016, Rio de Janeiro, Brazil , September, 2016 18. The blockchain as a software connector, Sherry Xu, Cesare Pautasso, Liming Zhu, Vincent Gramoli, Alexander Ponomarev, An Binh Tran and Shiping Chen. WICSA2016, Venice, Italy, April, 2016