status-im
/
eth2.0-specs
mirror of https://github.com/status-im/eth2.0-specs.git
2
0
Fork 0
Code Issues Projects Releases Wiki Activity

Attnet revamp draft

This commit is contained in:
Age Manning 2023-03-30 14:09:16 +11:00
parent ca4468da0d
commit 7cb1630902
No known key found for this signature in database
GPG Key ID: 05EED64B79E06A93
1 changed files with 24 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

33
specs/phase0/validator.md
View File

@ -88,10 +88,11 @@ All terminology, constants, functions, and protocol mechanics defined in the [Ph
| Name | Value | Unit | Duration |
| - | - | :-: | :-: |
| `TARGET_AGGREGATORS_PER_COMMITTEE` | `2**4` (= 16) | validators | |
| `RANDOM_SUBNETS_PER_VALIDATOR` | `2**0` (= 1) | subnets | |
| `EPOCHS_PER_RANDOM_SUBNET_SUBSCRIPTION` | `2**8` (= 256) | epochs | ~27 hours |
| `TARGET_AGGREGATORS_PER_COMMITTEE` | `2**4` (= 16) | validators |
| `EPOCHS_PER_SUBNET_SUBSCRIPTION` | `2**8` (= 256) | epochs | ~27 hours |
| `ATTESTATION_SUBNET_COUNT` | `64` | The number of attestation subnets used in the gossipsub protocol. |
| `ATTESTATION_SUBNET_EXTRA_BITS` | 0 | The number of extra bits of a NodeId to use when mapping to a subscribed subnet |
| `SUBNETS_PER_NODE` | 2 | The number of long-lived subnets a beacon node should be subscribed to. |
## Containers
@ -606,15 +607,29 @@ def get_aggregate_and_proof_signature(state: BeaconState,
## Phase 0 attestation subnet stability
Because Phase 0 does not have shards and thus does not have Shard Committees, there is no stable backbone to the attestation subnets (`beacon_attestation_{subnet_id}`). To provide this stability, each validator must:
Because Phase 0 does not have shards and thus does not have Shard Committees, there is no stable backbone to the attestation subnets (`beacon_attestation_{subnet_id}`). To provide this stability, each beacon node should:
* Randomly select and remain subscribed to `RANDOM_SUBNETS_PER_VALIDATOR` attestation subnets
* Maintain advertisement of the randomly selected subnets in their node's ENR `attnets` entry by setting the randomly selected `subnet_id` bits to `True` (e.g. `ENR["attnets"][subnet_id] = True`) for all persistent attestation subnets
* Set the lifetime of each random subscription to a random number of epochs between `EPOCHS_PER_RANDOM_SUBNET_SUBSCRIPTION` and `2 * EPOCHS_PER_RANDOM_SUBNET_SUBSCRIPTION]`. At the end of life for a subscription, select a new random subnet, update subnet subscriptions, and publish an updated ENR
* Remain subscribed to `SUBNETS_PER_NODE` for `SUBNET_DURATION_IN_EPOCHS` epochs.
* Maintain advertisement of the selected subnets in their node's ENR `attnets` entry by setting the selected `subnet_id` bits to `True` (e.g. `ENR["attnets"][subnet_id] = True`) for all persistent attestation subnets.
* Select these subnets based on their node-id as specified by the following
`compute_subnets(node_id,epoch)` function.
*Note*: Short lived beacon committee assignments should not be added in into the ENR `attnets` entry.
```python
ATTESTATION_SUBNET_PREFIX_BITS = ceil(log2(ATTESTATION_SUBNET_COUNT)) + ATTESTATION_SUBNET_EXTRA_BITS
*Note*: When preparing for a hard fork, a validator must select and subscribe to random subnets of the future fork versioning at least `EPOCHS_PER_RANDOM_SUBNET_SUBSCRIPTION` epochs in advance of the fork. These new subnets for the fork are maintained in addition to those for the current fork until the fork occurs. After the fork occurs, let the subnets from the previous fork reach the end of life with no replacements.
def compute_subnet(node_id, epoch, index):
node_id_prefix = node_id >> (256 - ATTESTATION_SUBNET_PREFIX_BITS)
permutation_seed = hash(uint_to_bytes(epoch // SUBNET_DURATION_IN_EPOCHS))
permutated_prefix = compute_shuffled_index(node_id_prefix, 1 << ATTESTATION_SUBNET_PREFIX_BITS, permutation_seed)
return (permutated_prefix + index) % ATTESTATION_SUBNET_COUNT
def compute_subnets(node_id, epoch):
return [compute_subnet(node_id, epoch, idx) for idx in range(SUBNETS_PER_NODE)]
```
*Note*: Nodes should subscribe to new subnets and remain subscribed to old subnets for at least one epoch. Nodes should pick a random duration to unsubscribe from old subnets to smooth the transition on the exact epoch boundary of which the shuffling changes.
*Note*: When preparing for a hard fork, a validator must select and subscribe to subnets of the future fork versioning at least `EPOCHS_PER_SUBNET_SUBSCRIPTION` epochs in advance of the fork. These new subnets for the fork are maintained in addition to those for the current fork until the fork occurs. After the fork occurs, let the subnets from the previous fork reach the end of life with no replacements.
## How to avoid slashing