In this keynote, delivered at the Blockchain Forum of BPM 2019, I summarized and reflected on research on BPM and blockchain over the last four years, including model-driven engineering, process execution, and analysis and process mining. I also covered selected use cases and applications, as well as recent insights on adoption. The keynote closed with a discussion of open research questions.
Blockchain and BPM - Reflections on Four Years of Research and Applications
1. Blockchain and BPM –
Reflections on Four Years of Research and Applications
Prof. Dr. Ingo Weber | Chair for Software and Business Engineering | BPM Blockchain Forum 2019
ingo.weber@tu-berlin.de | linkedin.com/in/ingomweber/ | Twitter: @ingomweber
6. Blockchain 2nd gen – Smart Contracts
• 1st gen Bitcoin transactions are financial transfers
• Now Blockchain ledger can do that, and
store/transact any kind of data
• Blockchain can deploy and execute programs: Smart Contracts
• User-defined code, deployed on and executed by whole
network
• Can enact decisions on complex business conditions
• Can hold and transfer assets, managed by the contract itself
• Ethereum: pay per assembler-level instruction
7. Cryptocurrencies and Tokens
Cryptocurrencies
– ‘Baked in’ to the core platform of public blockchains -base currency of
blockchains
– Symbiotic relationship
– Blockchain keeps track of the ownership of portions of that currency, e.g.
Alice owned 2Ether, transferred 1 Ether to Bob, offered 0.01Ether to miner
– Cryptocurrency enables the incentive mechanism for blockchain
operations
Digital tokens
– Created and exchanged using smart contracts
– Represent assets
• Fungible asset: individual units are interchangeable, e.g. company share,
gold
• Non-fungible asset: represents a unique asset, e.g. cryptokitties, car title
Not all applications are the same:
– Transferring coins / tokens vs. tracking movement of physical goods
– Core difference: where is the default version of the truth, on or off-chain?
8. Fungible and Non-fungible Tokens
Fungible tokens: interchangeable
– E.g., $2 coin, $10 note
– Main concern: how many?
– Ethereum: ERC20 standard
• https://theethereum.wiki/w/index.p
hp/ERC20_Token_Standard
• Example: OmiseGO (OMG).
“The OmiseGO blockchain comprises a
decentralized exchange, liquidity provider
mechanism, clearinghouse messaging
network, and asset-backed blockchain
gateway. … It uses the mechanism of a
protocol token to create a proof-of-stake
blockchain to enable enforcement of market
activity amongst participants. Owning OMG
tokens buys the right to validate this
blockchain, within its consensus rules.”
Non-fungible tokens
– E.g., houses, cars, patents
– Main concern: which ones?
– Ethereum: ERC721
• https://github.com/ethereum/EIPs/i
ssues/721
• Example: cryptokitties
https://www.cryptokitties.co/
• Kitties are non-fungible, individual,
and their appearance depends on
the individual features
9. What is a Blockchain?
Parable of the blind men and the elephant, see e.g., https://wildequus.org/2014/05/07/sufi-story-blind-men-elephant/
(source of figure)
10. What is a Blockchain?
No, it’s a
code
execution
platform!
It‘s a
database!
Actually,
it‘s a
network!
Clearly,
it’s a
BPMS!
Parable of the blind men and the elephant, see e.g., https://wildequus.org/2014/05/07/sufi-story-blind-men-elephant/
(source of figure)
11. Defining Blockchain (1)
Distributed Ledger
• An “append-only” transaction store distributed across machines
• A new transaction might reverse a previous transaction, but both remain part of
the ledger
Blockchain
• A distributed ledger structured into a linked list of blocks.
• Each block contains an ordered set of transactions
• Use cryptographic hashes to secure the link from a block to its predecessor.
12. Defining Blockchain (2)
A Blockchain System consists of
• A blockchain network of nodes
• A blockchain data structure
– For the ledger replicated across the blockchain network
– Full nodes hold a full replica of the ledger
• A network protocol
– Defines rights, responsibilities, and means of communication, verification, validation, and
consensus across the nodes in the blockchain network
– Includes ensuring authorization and authentication of new transactions, mechanisms for
appending new blocks, incentive mechanisms
13. Defining Blockchain (3)
A Public Blockchain is a blockchain system with the following characteristics:
• Has an open network
– Nodes can join and leave without requiring permission from anyone
• All full nodes can verify new transactions and blocks
• Incentive mechanism to ensure the correct operation
» Valid transactions are processed and included in the ledger and invalid
transactions are rejected
A Blockchain Platform is the technology needed to operate a blockchain
• Blockchain client software for processing nodes
• The local data store
• Alternative clients to access the blockchain network
14. Decentralized Applications and Smart Contracts
Smart contracts
• Programs deployed as data and executed in transactions on the blockchain
• Blockchain can be a computational platform (more than a simple distributed database)
• Code is deterministic and immutable once deployed
• Can invoke other smart contracts
• Can hold and transfer digital assets
Decentralized applications or dapps
• Main functionality is implemented through smart contracts
• Backend is executed in a decentralized environment
• Frontend can be hosted as a web site on a centralized server
» Interact with its backend through an API
• Could use decentralized data storage such as IPFS
• “State of the dapps” is a directory recorded on blockchain: https://www.stateofthedapps.com/
15. Book: Architecture for Blockchain Applications
Xiwei Xu, Ingo Weber, Mark Staples.
Architecture for Blockchain Applications.
Springer, 2019.
➔ Includes definitions for the terms on the previous slides
16. Functions Blockchain can Provide in a Dapp
Blockchain as…
Ingo Weber
16 |
Architectural
Element
Communi-
cation
Mechanism
Asset
Management
and Control
Mechanism
Storage
Element
Computational
Element
17. Blockchain Non-functional Properties
Immutability
• If data is contained in a committed transaction, it will eventually become
immutable
Non-repudiation
• The immutable chain of cryptographically-signed historical transactions
provides non-repudiation of the stored data
Integrity: cryptographic tools support data integrity
Transparency: public access (on permission-less blockchains)
Equal rights
• Allows every participant the same ability to access and manipulate the
blockchain
• Trust: Achieved from the interactions between nodes within the network
• Censorship resistance
18. Blockchain Non-functional Properties
Data privacy
• No privileged users
• Tradeoff between data privacy and transparency
Scalability
• Size of the data: due to the global replication of all data across the network
• Transaction throughput: 3-20 transactions per second (tps)
– VISA network handles 1700 tps on average
• Latency of data transmission
– Write latency caused by propagation
– Number of transactions included in each block (1MB for bitcoin)
– Latency between submission and confirmation caused by consensus protocol
All addressed through various research and development
– But there is no one-size-fits-all solution (yet?)
Limitations
20. Blockchain in
Production (1)
R3 Corda claimed 10
productive deployments at
the end of 2018 (some
confidential). Examples:
• India’s Federal Bank:
remittance
• GuildOne: energy
R3 CorDapps marketplace:
21. Blockchain in
Production (1)
R3 Corda claimed 10
productive deployments at
the end of 2018 (some
confidential). Examples:
• India’s Federal Bank:
remittance
• GuildOne: energy
R3 CorDapps marketplace:
R3’s CEO David Rutter:
“Pretend for a moment that you have this crazy idea that you want to deploy new technology
that could change everything about business, everything about the business processes…”
Corda’s Lead Platform developer Mike Hearn:
“It’s just little ad hoc business processes that would traditionally be done by people because
software development is too expensive. But we make it cheap enough and scaled down
enough that we could end up with millions of these apps.”
Source: https://www.ledgerinsights.com/brics-explore-blockchain-for-trade-finance/
22. Blockchain in Production (2)
Hyperledger use cases in production:
• Food source tracking using blockchain
• Ensuring food safety and quality (data: location, certifications, temperature, test results)
• Used by Golden State Foods, McCormick and Co., Nestlé, Tyson Foods and Wal-Mart Stores Inc., and more
• Blockchain for the airline industry
• Passenger ticketing processes (transparency “to help improve record-keeping, save money and improve
security and agility in a complex business.”)
• Developed by NIIT Technologies
• Traceability of organic coffee
• Traceable supply chain, from harvesting to roasting, packaging, and shipping
• Used by Cambio Coffee
• Blockchain for better enterprise operations management
• “to streamline operational procedures such as tracking and tracing the movement of goods, charity donations,
authenticity certification, property assessment, transaction settlements, digital copyrights and more.”
• Used by JD.com (China’s largest retailer) in its Retail-as-a-Service offering, e.g., China Pacific Insurance
Company for traceable e-invoices
• Blockchain for insurance compliance data
• “to automate insurance regulatory reporting”
• Developed by the American Association of Insurance Services
Source: https://www.hyperledger.org/blog/2018/11/30/six-hyperledger-blockchain-projects-now-in-production
23. Selected Blockchain Projects
Australian Securities Exchange:
• Settlement of trades to be sped up from 2-3 days to minutes, freeing up billions of $$
• Under development, industry engagement & testing ongoing
• Go-live of the blockchain system planned for March or April 2021
Modum.io:
• Ensure drugs do not exceed a temperature threshold
• Tamper-proof IoT device & blockchain storage of data
• Otherwise: use refrigeration trucks, 4-8x pricier
Australian National Blockchain
• Joint initiative by IBM, Data61 CSIRO, HSF, KWM
• Platform for blockchain-based legal contracts
• For a fee, implement your business contracts in code
24. Some Challenges for Blockchain Adoption
2018 was said to be the year of wide-spread productive deployment for
blockchain…
…which did not happen to that degree. Why?
Some challenges:
1.Can you find a trade-off between confidentiality and transparency that all
parties find acceptable?
2.Is the system dominated by a single entity?
3.Do you need a blockchain? Does it offer significant benefits?
25. 2018 was said to be the year of wide-spread productive deployment for
blockchain…
…which did not happen to that degree. Why?
Some challenges:
1.Can you find a trade-off between confidentiality and transparency that all
parties find acceptable?
2.Is the system dominated by a single entity?
3.Do you need a blockchain? Does it offer significant benefits?
Some Challenges for Blockchain Adoption
26. 2018 was said to be the year of wide-spread productive deployment for
blockchain…
…which did not happen to that degree. Why?
Some challenges:
1.Can you find a trade-off between confidentiality and transparency that all
parties find acceptable?
2.Is the system dominated by a single entity?
3.Do you need a blockchain? Does it offer significant benefits?
Do companies talk about their productive systems, or just about PoCs?
Some Challenges for Blockchain Adoption
27. 2018 was said to be the year of wide-spread productive deployment for
blockchain…
…which did not happen to that degree. Why?
Some challenges:
1.Can you find a trade-off between confidentiality and transparency that all
parties find acceptable?
2.Is the system dominated by a single entity?
3.Do you need a blockchain? Does it offer significant benefits?
Do companies talk about their productive systems, or just about PoCs?
Some Challenges for Blockchain Adoption
28. Disruptive Potential? (1/3)
Many articles call blockchain a disruptive technology
Think about the disruption caused by the World Wide Web and the cloud:
– WWW changed the lives of consumers, cloud changed the lives of the producers
Blockchain’s most direct impact will likely be in the backend
– But there are exceptions – especially where there is no centralized authority or it
cannot be trusted, or going around it pays off
– Example: the Zaatari refugee camp in Jordan that ‘runs’ on blockchain
Based on Foreword of our book by Len Bass, PhD, CMU
29. Disruptive Potential? (2/3)
Example: the Zaatari refugee camp in Jordan that
‘runs’ on blockchain
– See https://www.technologyreview.com/s/610806/inside-the-jordan-refugee-
camp-that-runs-on-blockchain/
Iris scan allows refugees to spend money from
their blockchain accounts
Outcomes:
– Saves approx. 98% of fees - similar to the use case
of international money transfers through blockchain
– Might serve as identity solution, in absence of
government IDs
Based on Foreword of our book by Len Bass, PhD, CMU
30. Disruptive Potential? (3/3)
Disruptive use cases?
– Supply chain: increase efficiency, decrease latency and fees
– Proof of identity:
• Most disruptive if respective government authorities are dysfunctional or uncooperative
• Virtual driver licence in NSW said to use blockchain (but details unknown as yet)
Advantages of using blockchain can be substantial, but not necessarily
disruptive to the consumer
Based on Foreword of our book by Len Bass, PhD, CMU
31. Reflection
However, Amara’s law says:
“We tend to overestimate the effect of a technology in the short run
and underestimate the effect in the long run.”
Some other insights
– 120 Blockchain startups in Berlin alone
– Harder for established companies? How hard is it to accept the implications &
changes that come with blockchain?
– Analogy with Uber?
– Analogy with Dotcom bubble?
33. 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”
Cross-organizational processes: by now a common use
case for blockchain applications
34. Blockchain-based Process Execution
Different modeling paradigms for blockchain-based processes:
– Flow-based [1-11]
• Activity-centric, BPMN-based [1-10]
– Single-pool BPMN Process Diagrams [2,5]
– BPMN Choreography Diagrams [1,11]
• Artifact-centric [11]
– Declarative [14]
– Rule-based [13]
– Flexible: participants decide on-the-go, blockchain tracks execution [12]
Code generation vs. interpretation [8]
Static vs. dynamic role binding [4]
BPMS [5] vs. MDE [9]
Ethereum vs. Bitcoin [12]
Integration with asset control and management / registries [9]
Integration with traditional BPMS: blockchain connector, e.g., Bonita, Bizagi
35. Advantages of MDE vs. Coding in the Blockchain Context
Code generation can implement best practices and well-tested building blocks
– Code can adhere to blockchain “standards” (like ERC-20, ERC-721, …)
Improved productivity, especially for novices in a particular technology
– However: someone should understand the code and review it
Models can be independent of specific blockchain technologies or platforms
– Avoid lock-in to specific blockchain technologies
Models are often easier to understand than code – particularly useful in
communicating with business partners about smart contracts
– Facilitates building trust
– Domain experts can understand how their ideas are represented in the system
37. 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 provides:
• Independent, global process monitoring
• Conformance checking: only expected messages are
accepted, only from the respective role
• Automatic payments & escrow
• Data transformation
• Encryption
39. 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*
40. 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*
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
41. Translator
Translate subset of BPMN elements to Solidity
– BPMN Choreography diagrams or regular BPMN models with lanes
Order goods
Bulk Buyer
Manufacturer
Place order for
supplies
Manufacturer
Middleman
+
Forward order for
supplies
Middleman
Supplier
Place order for
transport
Middleman
Special carrier
+
Deliver supplies
Special carrier
Manufacturer
Report start of
production
Manufacturer
Bulk Buyer
Deliver goods
Manufacturer
Bulk Buyer
Send waybill
Supplier
Special carrier
Request details
Special carrier
Supplier
Provide details
Supplier
Special carrier
42. Caterpillar Design Principle: Models with a Single Pool
Model the collaborative process as if it were an intra-organizational business
process executed on top of a traditional BPMS
– In other words, the collaborative process is modeled as if all the parties shared the
same process execution infrastructure (the blockchain).
→ Model as a single-pool BPMN Process Diagram
– not a collaborative process or a choreography where parties communicate via
messages
– Each independent party in the process is represented as a lane
– Hand-offs between parties are simply represented via sequence flows that go from
one lane to another (and not via messages).
43. Caterpillar Design Principle: Models with a Single Pool
Model the collaborative process as if it were an intra-organizational business
process executed on top of a traditional BPMS
– In other words, the collaborative process is modeled as if all the parties shared the
same process execution infrastructure (the blockchain).
→ Model as a single-pool BPMN Process Diagram
– not a collaborative process or a choreography where parties communicate via
messages
– Each independent party in the process is represented as a lane
– Hand-offs between parties are simply represented via sequence flows that go from
one lane to another (and not via messages).
45. Blockchain Functions vs. Approaches
Blockchain as…
Architectural
Element
Communi-
cation
Mechanism
Asset
Management
and Control
Mechanism
Storage
Element
Computational
Element
Caterpillar
46. Blockchain Functions vs. Approaches
Blockchain as…
Choreography-based approach → BPM Research Track S4: Tue 5:00pm
Architectural
Element
Communi-
cation
Mechanism
Asset
Management
and Control
Mechanism
Storage
Element
Computational
Element
Choreography-based
approach
47. Blockchain Functions vs. Approaches
Blockchain as…
Architectural
Element
Communi-
cation
Mechanism
Asset
Management
and Control
Mechanism
Storage
Element
Computational
Element
Lorikeet
50. Process Mining / Analytics
Process mining can be used to understand how clients and software interact
– Also for blockchain applications and dapps
But: understanding log data from blockchain is hard [18]
Two independent approaches, both presented at BPM 2019, tackle the problem
– “Mining Blockchain Processes: Extracting Process Mining Data from Blockchain
Applications” [16] → Blockchain Forum Session 2, Wednesday 11:00am - 12:30pm
• Can be used on any blockchain application, designed with process-awareness or not
– “Extracting Event Logs for Process Mining from Data Stored on the Blockchain” [19]
→ SPBP Workshop, Monday 4:00pm - 5:30pm
• Makes the assumption that the blockchain data was generated from executing a process
model
52. Some General Observations
Keep an eye on “cost”, even on private networks
– Cost reflects effort, and that impacts all blockchain networks
– Tamper-proof, immutable, lasting storage tends to be most expensive
→ Binary encoding of variables helps
Blockchain ensures integrity of data and computation, but not data quality
53. Some General Observations
Keep an eye on “cost”, even on private networks
– Cost reflects effort, and that impacts all blockchain networks
– Tamper-proof, immutable, lasting storage tends to be most expensive
→ Binary encoding of variables helps
Blockchain ensures integrity of data and computation, but not data quality
One approach for data from
outside objects: check
digital-physical parity [17]
– Example: food traceability
X
56. Seven Challenges from [15] (1/2)
1. Developing a diverse set of execution and monitoring systems on blockchain.
Research in this area will have to demonstrate the feasibility of using blockchains for
process-aware information system. […]
2. Devising new methods for analysis and engineering business processes based on
blockchain technology. Research in this topic area will have to investigate how
blockchain-based processes can be efficiently specified and deployed. […]
3. Redesigning processes to leverage the opportunities granted by blockchain.
Research in this context will have to investigate how blockchain may allow re-
imagining specific processes and the collaboration with external stakeholders. The
whole area of choreographies may be re-vitalized by this technology. […]
4. Defining appropriate methods for evolution and adaptation. Research in this area will
have to investigate the potential guarantees that can be made for certain types of
evolution and adaptation. […]
Progress
(indicative)
57. Seven Challenges from [15] (2/2)
5. Developing techniques for identifying, discovering, and analyzing relevant processes
for their adoption of blockchain technology. Research on this topic will have to
investigate, which characteristics of blockchain as a technology best meet
requirements of specific processes. […]
6. Understanding the impact on strategy and governance of blockchains, in particular
regarding new business and governance models enabled by revolutionary innovation
based on blockchain. Research in this topic area will have to study which processes
in an enterprise setting could be organized differently using blockchain and which
consequences this brings. […]
7. Investigating the culture shift towards openness in the management and execution of
business processes, and on hiring as well as upskilling people as needed. Research
in this topic area will have to investigate how corporate culture changes with the
introduction of blockchains, and in how far this differs from the adoption of other
technologies. […]
?
?
Progress
(indicative)
58. Some Additional Challenges
Privacy / confidentiality vs. transparency
– Better trade-offs needed
– For instance, different visibility settings needed for different subprocesses, but with
integrity guarantees (see e.g. Master thesis of Jan Ladleif, HPI)
More seamless integration between on-chain and off-chain process parts
– Revive the concepts of public/private processes?
– Challenging, because all parties might have different private processes they won’t
share (otherwise these wouldn’t be private)
Much more work to be done on process mining / analysis
– Two works presented at this conference, both show technical feasibility of extracting
data from blockchain
60. Summary
Introduction
– Main insights on blockchain-based application architecture
– Defining Blockchain
Blockchain Adoption to Date
– Past the peak of the hype
– Some productive deployments, some dramatic improvements
• But not as many quick wins as some may have thought
State of the Art: Blockchain and BPM
– Lots of work on execution
– Process mining of blockchain data is starting
Open questions
– More research needed
“Modeling and Enforcing Blockchain-Based Choreographies” → BPM Research Track S4: Tue 5:00pm
“Mining Blockchain Processes: Extracting Process Mining Data from Blockchain Applications” [16]
→ Blockchain Forum Session 2, Wednesday 11:00am - 12:30pm
62. Thank you for your
attention!
Blockchain and BPM –
Reflections on Four Years of Research and Applications
Prof. Dr. Ingo Weber | Chair for Software and Business Engineering | BPM Blockchain Forum 2019
ingo.weber@tu-berlin.de | linkedin.com/in/ingomweber/ | Twitter: @ingomweber
63. References
1. Ingo Weber, Sherry Xu, Regis Riveret, Guido Governatori, Alexander Ponomarev and Jan Mendling. Untrusted business
process monitoring and execution using blockchain. BPM 2016, Rio de Janeiro, Brazil , September, 2016
2. L. Garcia-Banuelos, A. Ponomarev, M. Dumas, and I. Weber, “Optimized execution of business processes on blockchain,” in
BPM, 2017, pp. 130–146.
3. A. Tran, Q. Lu, and I. Weber, “Lorikeet: A model-driven engineering tool for blockchain-based business process execution
and asset management,” in Demo Track at BPM, 2018, pp. 56–60.
4. O. Lopez-Pintado, M. Dumas, L. Garcia-Banuelos, and I. Weber, “Dynamic role binding in blockchain-based collaborative
business processes,” in CAiSE, 2019, pp. 399–414.
5. O. Lopez-Pintado, L. Garcia-Banuelos, M. Dumas, I. Weber, and A. Ponomarev, “Caterpillar: A business process execution
engine on the Ethereum blockchain,” Software: Practice and Experience, pp. 1162–1193, 2019.
6. H. Nakamura, K. Miyamoto, and M. Kudo, “Inter-organizational business processes managed by blockchain,” in WISE, 2018,
pp. 3–17.
7. G. Falazi, M. Hahn, U. Breitenbücher, and F. Leymann, “Modeling and execution of blockchain-aware business processes,”
SICS Software-Intensive Cyber-Physical Systems, 2019.
8. Orlenys López-Pintado, Marlon Dumas, Luciano García-Bañuelos, and Ingo Weber. Interpreted execution of business
process models on blockchain. In EDOC'19: IEEE International Enterprise Computing Conference, October 2019.
9. An Binh Tran, Qinghua Lu, and Ingo Weber. Lorikeet: A model-driven engineering tool for blockchain-based business
process execution and asset management. In BPM'18: International Conference on Business Process Management, Demo
track, Sydney, NSW, Australia, September 2018.
10. Jan Ladleif, Mathias Weske, and Ingo Weber. Modeling and enforcing blockchain-based choreographies. In BPM'19:
International Conference on Business Process Management, Vienna, Austria, September 2019.
64. References
11. Hull R, Batra V.S, Deutsch Y Chenband A, III F.F.T Heath, Vianu V. Towards a Shared Ledger Business Collaboration
Language Based on Data-Aware Processes. In: Proceedings of 14th International Conference on Service-Oriented
Computing, ICSOC 2016, Banff, AB, Canada; 2016.
12. C. Prybila, S. Schulte, C. Hochreiner, and I. Weber, “Runtime verification for business processes utilizing the bitcoin
blockchain,” Future Generation Computer Systems, 2017
13. Idelberg, Florian and Governatori, Guido and Riveret, Regis and Sartor, Giovanni. Evaluation of Logic-Based Smart
Contracts for Blockchain Systems. 10th International Web Rule Symposium, July, 2016
14. Madsen, M. F., Gaub, M., Høgnason, T., Kirkbro, M. E., Slaats, T., & Debois, S. (2018). Collaboration among Adversaries:
Distributed Workflow Execution on a Blockchain. 2018 Symposium on Foundations and Applications of Blockchain.
15. Jan Mendling, Ingo Weber, Wil Van Der Aalst, Jan vom Brocke, Cristina Cabanillas, Florian Daniel, Søren Debois, Claudio Di
Ciccio, Marlon Dumas, Schahram Dustdar, Avigdor Gal, Luciano García-Bañuelos, Guido Governatori, Richard Hull,
Marcello La Rosa, Henrik Leopold, Frank Leymann, Jan Recker, Manfred Reichert, Hajo A. Reijers, Stefanie Rinderle-Ma,
Andreas Solti, Michael Rosemann, Stefan Schulte, Munindar P. Singh, Tijs Slaats, Mark Staples, Barbara Weber, Matthias
Weidlich, Mathias Weske, Xiwei Xu, and Liming Zhu. Blockchains for business process management - challenges and
opportunities. ACM Transactions on Management Information Systems (TMIS), 9(1):4:1-4:16, February 2018.
16. Christopher Klinkmüller, Alex Ponomarev, An Binh Tran, Ingo Weber, and Wil van der Aalst. Mining blockchain processes:
Extracting process mining data from blockchain applications. In Blockchain Forum of the International Conference on
Business Process Management (BPM), Vienna, Austria, September 2019.
17. Sin Kuang Lo, Xiwei Xu, Chen Wang, Ingo Weber, Paul Rimba, Qinghua Lu, and Mark Staples. Digital-physical parity for
food fraud detection. In ICBC'19: International Conference on Blockchain, San Diego, CA, USA, June 2019.
18. Di Ciccio, Claudio; Cecconi, Alessio; Mendling, Jan; Felix, Dominik; Haas, Dominik; Lilek, Daniel; Riel, Florian; Rumpl,
Andreas; Uhlig, Philipp. Blockchain-Based Traceability of Inter-organisational Business Processes. In BMSD 2018.
19. Mühlberger, Roman; Bachhofner, Stefan; Di Ciccio, Claudio; García-Bañuelos, Luciano; Pintado, Orlenys. (2019). Extracting
Event Logs for Process Mining from Data Stored on the Blockchain.