chaincraft

Chaincraft: The platform for blockchain education and prototyping

Roadmap

• Gossip: Sharing JSON messages between the nodes (SharedMessage).
• Permanent storage: the JSON messages are stored in key/value.
• Discovery: Global or Local Discovery of new nodes.
• Mandatory and Optional Fields and Types: Some format for JSON, prevalidation. Ban peers sending invalid format.
• SharedObject list that is updated by SharedMessages (inside can go Linked Fields Chaining). Ban peers sending invalid messages.
• Merklelized Storage: to know quicker when some a SharedObject is broken or which index for a linear array of messages/blocks.
• Primitives (RSA, ECSA, VDF, VRF, Signature Aggregation, LSH, Quantum-resistant Primitives)
• Indexing (MongoDB-like)

SharedMessage

• prevalidation(message) : boolean with mandatory/optional fields and types.
• Test isValid(message) for all SharedObjects like Ledgers or Mempools.
• Do update for all shared objects with addMessage(message).

SharedObject

• isValid(SharedMessage) : boolean: a message m if valid is all( isValid(m ) for o in sharedObject)
• addMessage(ShareMessage) : void: is "added" to all ShredObjects if is valid like [o.addMessage(m) for o in sharedObject]
• isMerkelized()/hasDigest() : boolean
• getDigest() : SharedMessage
• isValidDigest() : boolean to check if the digest for the shared object is valid.
• gossipObject(peer,myDigest) : List(SharedMessage) to sync the SharedObject locally, requesting more messages.
• Local SharedObject gossip using hasDigest(), getDigest(), gossipObject() and isValidDigest().

Example (Bitcoin)

• The shared object are Ledger and Mempool.
• A bitcoin transaction tx is only a transfer for simplicity.
• Example: Ledger.isValid(tx) is true if the sender has enough balance in account to do the transfer.
• Example Mempool.addMessage(tx) will do a sorted insert into the priority queue of Mempool based on the fee that the sender is paying, higher fees gets more priority to be included in the next block of transactions.

Design Principles for Prototyping Blockchains and Protocols

• Blockchain Trilemma (Tradeoff):
  • Security
  • Scalability
  • Decentralization
• Time Synchronization (Tradeoff): having better synced time has pros and cons.
  • Totally Async (no validation of timestamps)
  • Eventually Synced (timestamps are used for some things, but you accept timestamp far away in time)
  • Bounded Synced Time (timestamp +/- delta are the only valid messages, where delta is 15 seconds for example).
  • Totally Time-synced, like depend on time being totally synced.
• Identity and Anon User (Tradeoff):
  • Totally Anon Users.
  • Anon Users w/Resources (think Proof-of-Work without signatures)
  • Identified with Signatures.
  • Signature plus protocol to accept the new identity (think adding a validator to Proof-of-Stake).
• Levels of Data Synchronization:
  • Torrent: very liberal and concurrent.
  • Blockchain: very restrictive and sequential.
  • Middle-ground: decentralized app (non-financial)
    • Eventually consistent.
    • All data is validated.
    • Example1: Decentralized Messenger (santi).
    • Example2: Decentralized AI

Brainstorming in DeAI

• Prededetemined Training Sample Blocks List: B1, B2, ..., Bn..
• Eventually: block Bi is processed.
• Is Okey if Bn is processed and validated and distributed and B(n-1) is not yet available.
• Alternative: a node can propose Bn if is missing, Bn-1 is known, or wants to replace existing Bn.

Run tests

Run all tests:

python -m unittest discover -v -s tests

Result:

...
----------------------------------------------------------------------
Ran 38 tests in 61.963s

OK

A single testfile:

python -m unittest tests/test_start.py

To run a single test inside a testfile:

python -m unittest -v -k test_local_discovery_enabled tests/test_local_discovery.py