About Me

Marten (Wiebe-Marten Wijnja)

• ~12 years of software development
• ~6 years of blockchains
• ~1.5 years of Resilia

Online: Qqwy

Contents

• Rationale
• Four major concepts
  • short intro of 1 concept
  • ~10-15 minutes of peer (to peer) discussion
• Closing Thoughts

• Non-Technical
  • Not how it works
  • but: what it does
• Properties: Good, Bad, Unimportant?
• Ask Questions!

Style

Recap: What is a Blockchain?

A Blockchain is a software system in which:

• All data is immutable
• Anyone can join and add data
• All members agree about the order of the data

Both large potential and large drawbacks!

• No Training Wheels
  • 'Forgot Password'
    
• Storing data is slow
• Can only store small bits of data at a time
  

Large potential, but large drawbacks:

Difficult to adapt current way of thinking

Solution:

Ease into it

Granular Blockchain

Hashing

• Making a unique colour or fingerprint based on your data chunk

Properties

• Small
• Reproducible
• Impossible to reverse

Example uses

• Password checking
• Integrity of files
• Making computers faster
• Authenticity (Plagiarism protection)

Hashing

Properties

• Small
• Reproducible
• Impossible to reverse

Example uses

• Password checking
• Integrity of files
• Making computers faster
• Authenticity (Plagiarism protection)

Hashing

Discuss!

Asymmetric Cryptography

• Encryption key separated from Decryption Key
  • Public encryption key
  • Private decryption key

• Private key can also be used to make signatures

Properties

• Send/receive encrypted messages

Signatures:

• data authenticity
• non-repudiation               ('I did not write that' is impossible)

Example uses

• HTTPS
• PGP (Secure Email)
• WhatsApp etc.
• Storing private data in public places

Asymmetric Cryptography

Properties

• Send/receive encrypted messages

Signatures:

• data authenticity
• non-repudiation               ('I did not write that' is impossible)

Example uses

• HTTPS
• PGP (Secure Email)
• WhatsApp etc.

Asymmetric Cryptography

Discuss!

Event Sourcing

• Store list of changes in system
  • Audit Trail/Ledger
• Calculate 'current state' whenever desired

Properties

• History is kept
• Author of change known
• Reprocess/analyze as much as you like

Example uses

• Banking systems
• Other administrative systems
• Sensor data
• 'event-driven' architectures

Event Sourcing

Properties

• History is kept
• Author of change known
• Reprocess/analyze as much as you like

Example uses

• Banking systems
• Other administrative systems
• Sensor data
• 'event-driven' architectures

Event Sourcing

Discuss!

Consensus

• Distributed (and maybe decentralized) system
• Multiple parties in agreement about 'state'
• Potentially unreliable network
• Potentially some unreliable parties

A Consortium/Private Blockchain is a software system in which:

• All data is immutable
• Anyone can join and add data
• All members agree about the order of the data

Consensus: 'Classical' Paxos, Raft, etc.

• Fast
• in use for 30+ years
• Small-ish amounts of data

a Decentralized Datastore is a software system in which:

• All data is immutable
• Anyone can join and add data
• All members agree about the order of the data

Consensus: Not needed, because no ordering

(Data integrity is checked by hashing)

• Super fast!
• HUGE amounts of data

Consensus

Summary

• Starting to use a Blockchain is difficult
• Four Concepts:
  • Hashing
  • Asymmetric Cryptography
  • Event Sourcing
  • Consensus
• Easing in: It's not all-or-nothing!
  • Use the right  tool for the right job

Thank you!