Slides of the talk on Parity Technologies & Polkadot at the Silicon Valley Ethereum meetup on 2017/10/08: https://www.meetup.com/de-DE/EthereumSiliconValley/events/243636714/?eventId=243636714

1. Björn Wagner
bjorn@parity.io
@bjornwgnr
paritytech.io

2. CORE BLOCKCHAIN TECHNOLOGY PROVIDER
Dr. Jutta Steiner | CEO Dr. Gavin Wood | CTO

3. ENTERPRISES
PUBLIC BLOCKCHAIN SPACE & BEYOND

5. FIVE KEY FAILURES OF CURRENT
BLOCKCHAIN TECHNOLOGY
Isolatability
Applicability
Scalability
Developability
Governance

6. WHAT IS POLKADOT?
Extensibility Scalability Heterogeneity

7. CURRENT APPROACH
SINGLE CHAIN
Varying degrees of generality over potential applications
State transition
mechanism
Consensus
“canonicalisation”
mechanism

8. POLKADOT APPROACH
RELAY-CHAIN
top-level which coordinates
consensus and transaction
delivery between constituents
PARACHAINS
contain logic and handle
transactions

9. WHAT DOES IT PROVIDE?
Pooled security: all constituent chains of our
community guaranteed
Trust-free transactions: constituent chains can send
transactions to each other

11. WHAT DOES IT PROVIDE?
Pooled security: all constituent chains of our
community guaranteed
Trust-free transactions: constituent chains can send
transactions to each other

12. WHAT DOES IT ENABLE?
PERMISSIONLESS CHAINS
like Ethereum, Zcash or potentially Bitcoin
&
PERMISSIONED CHAINS
i.e. encrypted Proof-of-Authority chains
TO RUN IN THE SAME NETWORK

14. UPDATE ON DEVELOPMENT
EXPANDING PROOF-OF-AUTHORITY
with misbehavior reporting and
stake-proportional drawing
INTEGRATING LIGHT-CLIENT SUPPORT
light client proofs of validation can be created
for each chain
BRIDGING ETHEREUM-LIKE CHAINS
sending messages between two chains with
a secure bridge

15. UPDATE ON DEVELOPMENT
ROBUST P2P NETWORKING
initially modifying devp2p, then moving to
libp2p
GENERALIZING OVER STATE MACHINES
plug in any transaction/account scheme in
Parity

16. FOLLOW THE PROGRESS
CODE:
github.com/w3f
github.com/paritytech/parity
CHAT:
gitter.im/w3f/polkadot-white-paper
TECH WEBSITE:
polkadot.io

17. Find out more
polkadot.network
Join the conversation
@polkadotnetwork
#polkadot-watercooler:matrix.org

18. BACKUP

19. BASICS OF THE RELAY-CHAIN
NO FUNCTIONALITY
No external transactions, no smart contracts
FEES MAY BE LEVIED
Fees paid according to decision of stakeholders

20. Polkadot network
Internal/consortium parachain
Authorities manage parachain
validation, access controls &c.
Transactions and
inter-chain consensus
Open parachains can be tightly integrated
into Polkadot, using Polkadot’s validators to
ensure their correct operation. They are the
easiest and cheapest form of integration.
Closed parachains can be weakly integrated
into Polkadot, giving them the freedom to
manage validation internally e.g. using a set of
recognised authorities.
Bridged chains can be integrated into
Polkadot too. Bridges add complexity and
cost to integration, but allow the chain to
exercise its own means of consensus.

21. WHO POWERS IT?
VALIDATORS
Verify parachain transactions and pass messages
NOMINATORS
Select good validators and increase economic security
COLLATORS
prepare parachain candidates and proofs of validity
FISHERMEN
keep a watchful eye that validators behave correctly

22. WHY DO THEY BOTHER?
VALIDATORS/NOMINATORS
Rewarded via staking-token expansion
COLLATORS
Parachain-specific transaction fees
FISHERMEN
Gifted proportion of the bond of identified culprit

23. EXTENSIBLE, SCALABLE AND
FLEXIBLE
Polkadot’s Relay-chain ensures that messages
between the constituent parachains get
delivered and that they are all operating
correctly.
Parachains can take any form of
globally-coherent consensus system;
potentially even another relay-chain.
Enterprise-friendly encrypted, private,
proof-of-authority chains are supported.
Bridges can exist to ferry transactions
between the relay chain and existing,
independent chains like Ethereum.

24. VALIDATORS, COLLATORS AND
FISHERMEN
Polkadot’s mechanics work by incentivising
three kinds of activity.
Collators work independently on each
parachain collecting and executing
transactions. They provide blocks of
transactions to validators.
Validators route messages between
parachains. They take turns vetting blocks
supplied by collators and finally sign off to
commit one to finality.
Fishermen receive a reward for reporting
misbehaving validators.

25. ACHIEVING CONSENSUS
RELAY-CHAIN PROOF-OF-STAKE
Guarantees shared canonicality of parachains
ECONOMIC FINALITY
Ensure changes and transactions cannot be reverted
PARALLEL VALIDATION GROUPS
Validators partitioned to allow scaling

26. NOTES ON GOVERNANCE
STAKEHOLDER-DRIVEN
Stakeholders hold power over protocol upgrades
COMMUNITY FOCUSED
A portion of block rewards put into a DAO