Blockchains
This is a notebook from [ブロックチェーン2.0概況](https://www.youtube.com/watch?v=3xGChlcsj_4).
# Blockchain No.12
## scriptless script on schnorr
This technique enables for a musician to send a music on blockchain,
with each time they make a schnorr signature.
## MAST
Merklized Abstract Syntax Tree enables partitioning of contract code and sharded storing of codes.
Each separated child script returns True to the parent script.
## Bitcoin
~~~
- FlyClient (extended spv : super light client)
- SPV client : only all blockheader
- using a technique, 'Merkle Mountain Range'
- Graphene (minimize the time taken for block propagation to 10% of CompactBlock)
- using Bloom filter and IBLT
- Bloom filter enables spv wallet to judge my transaction is included in a block
- IBLT enables to reconsile data pool called mempool
- former version: Xtreme Thinblock
- BUIP010
- Sharing 'memory pool (mempool)' stops duplication of including the same transactions in different blocks
- Bobtail(minimize the variaty of block time )
- 80% of blocktimes are in [1 min, 24 min]
- Microchain(smart phone full node)
- Bolt(completely Private payment channel) : we cannot detect who is sender, or receiver
- ValueShuffle(CoinJoin + Confidential Transaction)
- CoinJoin : use a mixed list of fresh addresses
- ValuShuffle apply Confidential Transaction to Coinjoin
- Discreet log Contract DLC
- using Schnorr signature and smart contracts, this solves the oracle problem
- oracle problem
- 2of2 multisig can cause a deadlock of deposit
- 2of3 multisig is preferable
- this third party 'oracle' can have a risk to be bought by one side.
- scriptless script
- run script without putting script on the chain
- XCAT(cross chain atomic swap trade)
- radio broadcasted bitcoin transactions
~~~
## Devcon(Ethereum)
~~~
- sharding : 2 universe
- main
- sub sharding network
- casper : POS
- FFG : used to move PoW to Pos
- CBC : consensus management after finishing migration to PoS
- plasma : multiple layer
- Inter Blockchain Communication IBC
- by Cosmos
- Zero knowledge proof satisfies
- Completeness
- Soundness
- Zero knowledge
- TrueBit
- make the calculation of smart contract off chain
~~~