1. CSE 552 preparation for reading
Blockchains
CSE 552
preparation for reading

2. Systematization of knowledge
A special kind of paper that appears in IEEE S&P
Doesn’t have new research
Surveys existing research
Provides a new viewpoint not necessarily understood by the purveyors of that research
A survey is useful to introduce yourself to a new area

3. A blockchain is a replicated state machine
...but with only probabilistic properties
...
The key is to ensure global consensus on the sequence of inputs
Header

4. Each block can succeed only one log prefix
hash
...

5. Consensus is on the hardest chain to produce
hash
PoW
...
“Work” is to find a such that the hash of the is less than the current target
nonce
block

6. Participation is motivated by payment
hash
PoW
...
$$$ for miner $
Adding a block to the chain (mining) lets you add a transaction creating currency in your personal account
A transaction can also specify that the miner gets whatever “change” is left over from running it

7. Distributed systems in a blockchain
The blockchain itself
The dissemination network
Lets clients send transactions to miners
Lets miners publicize the blocks they mine