A minimal sharding protocol that may be worthwhile as a development target now

hwwhww · April 8, 2018, 4:19am

Request for renaming and ordering for consistency:

addHeader(shard_id, chunk_root, period)
- period_id → period
- chunks_root → chunk_root

github.com/ethereum/sharding

SMC modification - stage 1

opened 04:49AM - 08 Apr 18 UTC

closed 03:27AM - 27 Jul 18 UTC

hwwhww

suspended

### What is wrong? [**Old** sharding spec](https://ethresear.ch/t/sharding-phas…e-1-spec/1407) + [A minimal sharding protocol](https://ethresear.ch/t/a-minimal-sharding-protocol-that-may-be-worthwhile-as-a-development-target-now/1650) ### How can it be fixed - [x] "collator" -> "notary" * e.g., `COLLATOR_DEPOSIT` -> `NOTARY_DEPOSIT` - [x] Add constant * `COMMITTEE_SIZE` := 135 * `QUORUM_SIZE` := 90 * Implement notary pool and notary registry: - [ ] `register_notary() returns bool`: Adds an entry to `notary_registry`, updates the notary pool (`notary_pool`, `notary_pool_len`, etc.), locks a deposit of size `NOTARY_DEPOSIT`, and returns `True` on success. Checks: * Deposit size: `msg.value >= NOTARY_DEPOSIT` * Uniqueness: `notary_registry[msg.sender]` does not exist - [ ] `deregister_notary() returns bool`: Sets the deregistered period in the `notary_registry` entry, updates the notary pool (`notary_pool`, `notary_pool_len`, etc.), and returns `True` on success. Checks: * Authentication: `notary_registry[msg.sender]` exists - [ ] `release_natory() returns bool`: Removes an entry from `notary_registry`, releases the notary deposit, and returns `True` on success. Checks: * Authentication: `notary_registry[msg.sender]` exists * Deregistered: `notary_registry[msg.sender].deregistered != 0` * Lockup: `floor(block.number / PERIOD_LENGTH) > notary_registry[msg.sender].deregistered + NOTARY_LOCKUP_LENGTH` - [x] `add_header(shard_id, chunk_root, period) returns bool`: anyone can call this function at anytime. The first header to get included for a given shard in a given period gets in, all others don’t. Returns `True` on success. This function just emits a log. * `HeaderAdded` log (emitted from SMC `add_header` function) * v1 ```python shard_id uint256 # pointer to shard chunk_root bytes32 # pointer to collation body period int128 # (current block number / PERIOD_LENGTH) proposer_address address # the address of proposer ``` * v2 compressed ```python shard_id bytes1 # pointer to shard chunk_root bytes32 # pointer to collation body period bytes3 # (current block number / PERIOD_LENGTH) proposer_address address # the address of proposer ``` - [x] `get_committee(shard_id, period) returns a list of addresses`: use the last block hash `h` before this period as the seed. Selecting `notary_pool[sha3(h) % notary_pool_size], notary_pool[sha3(h + 1) % notary_pool_size], .... notary_pool[sha3(h + (COMMITTEE_SIZE - 1)) % notary_pool_size]` notaries from `notary_pool`. - [ ] `submit_vote(shard_id, chunk_root, period) returns bool`: Sampled notaries call this function to submit vote, returns `True` on success. This function just emits a log. * `Vote` log (emitted from SMC `submit_vote` function) * v1 ```python shard_id uint256 # pointer to shard chunk_root bytes32 # pointer to collation body period int128 # (current block number / PERIOD_LENGTH) notary_address address # the address of notary ``` * v2 compressed ```python shard_id bytes1 # pointer to shard chunk_root bytes32 # pointer to collation body period bytes3 # (current block number / PERIOD_LENGTH) notary_address address # the address of notary ```