bde-sc6 hangout - “insight into virtual currency ecosystems”
TRANSCRIPT
Insight into Virtual Currency Ecosystems(by making use of Big Data technology)
Dr. Bernhard Haslhofer, Austrian Institute of Technology (AIT)
BDE SC6 Webinar, 2017-02-16
About me• Data Scientist @ Austrian Institute of
Technology / Digital Insight Lab
• Research Interest: gain insight from large, connected datasets using machine learning, network analytics and text mining methods
• Current focus: virtual currency analytics
• Project(s): GraphSense
2http://www.graphsense.info http://bernhardhaslhofer.info
Plan for today
• What are Virtual Currency Ecosystems?
• GraphSense | Goals, Features and Demo
• GraphSense | Technical Aspects
• Outlook and Challenges
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What are Virtual Currency Ecosystems?
Virtual Currency• “A type of unregulated, digital money, which is issued and
usually controlled by its developers, and used and accepted among the members of a specific virtual community.” (ECB)
• Functions: measure of value, medium of exchange, store of value
• Currency codes: XBT, ETH, XMR, ….
• Currency symbols: B⃦, Ξ, ɱ, …
• Exchange rates to other currencies (USD, EUR, …)
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Virtual Currency
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Centralized Decentralized
RegulatedE-money
Bank money (deposit)
Unregulated
Internet coupon
Mobile coupon
Centralized virtual currency
Cryptocurrencies (e.g., Bitcoin)
Non-Cryptocurrency (e.g., Ripple, Stellar)
based on https://en.wikipedia.org/wiki/Virtual_currency
• Difference to other currency systems:
• No pre-assumed identities
• No central authority, no trusted third parties
• collective transaction management (blockchain)
• collective money issuance (mining)
Cryptocurrency
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How do I make a Bitcoin transaction?
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P2P Network
Broadcast Transaction
Blockchain
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P2P Network
Blockchain
Miners
Collect pending Transactions
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P2P Network
Blockchain
Miners
Find a block
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P2P Network
Blockchain
Miners
Broadcast new block
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Miners
P2P Network
Synchronize Blocks
Blockchain
Receive Confirmations
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P2P Network
Synchronize Blocks
Blockchain
Receive Confirmations
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How do I get Bitcoins?
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Exchange
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2653 Markets
20Source: https://coinfinity.co/bitcoin-kaufen/
Bitcoin ATMs
Bitcoin Voucher Service
Who accepts Bitcoins?
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Merchants
Merchants
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Payment Providers
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Gambling Sites
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Darknet Marketplaces
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Mixing Services
Virtual Currency Ecosystem
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Gambling Sites
MinersMixing Services
Darknet MarketplacesMerchants
Payment ProvidersBitcoin
ATMs
Bitcoin Voucher Service
Exchange
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GraphSense | Goal, Features, and Demo
Goals and Features
• Provide insight into Virtual Currency Ecosystems
• Microscopic view: inspect atomic entities (block, transaction, address, currency flows)
• Macroscopic view: investigate real-world actors (exchanges, payment services, etc.) and the currency flows between them
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Approach
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GraphSense | Technical Aspects
Overall Architecture
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Data Processing (v.0.2.1)
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Data Processing (v.0.3)
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Cross-ledger Analytics
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L$
OM¢
Challenge #1: Volume• At the moment we only
process Bitcoin transactions
• raw data: 91 GB
• transformed: 217 GB
• DB (with indices): 757 GB
• There are at least 646 other virtual currencies
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Challenge #2: Variety
• Virtual currencies differ in their conceptual design
• Protocols change over time
• Need: flexible, horizontally scalable data storage
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Challenge #3: Velocity• Bitcoin blocks
• limited to 1MB (1000 - 2000 transactions)
• interval between blocks: ~10min
• block size will most likely grow in future
• Other currencies implement higher frequencies
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• GraphSense address graph
• ~ 212 million addresses (nodes)
• ~ 1.36 billion flows between addresses (edges)
• We need graph algorithms that
• compute connected components efficiently on large graphs
• leverage distributed computing paradigms (map-reduce)
• also work for large graphs with a skewed node degree distribution
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Challenge #4: Large Graphs
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Information & Contacts:� CESSDA, Ivana Ilijasic Versic, [email protected]
� Semantic Web Company, Martin Kaltenböck, [email protected]
� Austrian Institute for Technology, Bernhard Haslhofer, [email protected]
Big Data Europe – Information & Outlook� BDE website: http://www.big-data-europe.eu
� Mailing List: http://eepurl.com/bg3vCr
� Big Data Integrator Platform (BDI): https://www.big-data-europe.eu/platform/
� WATCH OUT: 3.5.2017 – Final BDI Release 16-févr.-17www.big-data-europe.eu