PoS
Proof-of-Stake (PoS) Authenticator
For security-critical operations — especially those involving subnet membership and DHT participation — Hypertensor recommends using the Proof-of-Stake (PoS) Authenticator.
This authenticator ensures that only nodes with a valid on-chain stake can:
Join the DHT
Update routing tables
Register heartbeat or protocol records
Participate in critical peer-to-peer interactions
How It Works
The PoS authenticator combines cryptographic identity verification with on-chain staking validation.
When a node attempts to make a DHT request, the authenticator:
Verifies the Peer ID Signature
Supports both RSA and Ed25519 schemes.
Ensures the peer controls the corresponding private key.
Checks On-Chain Stake
Queries the Hypertensor blockchain to verify that the peer ID is staked in the target
subnet_id.Prevents unauthenticated or free-rider nodes from participating in the network.
Caches the Result
After a successful stake verification, the result is cached for 5 minutes to reduce load on the chain.
This cooldown ensures a balance between security and performance.
When to Use It
The PoS Authenticator is ideal for:
Joining the DHT
Updating DHT routing tables
Publishing or modifying DHT records
Authenticating peers in sensitive protocols (e.g., scoring, validation, consensus)
⚠️ Nodes without a valid stake will be rejected from performing any critical or trusted actions in the network.
Built-In Support
The Hypertensor subnet template includes ready-to-use PoS authenticators for:
Ed25519RSA
You can select the appropriate one depending on your key infrastructure.
class Ed25519ProofOfStakeAuthorizer(AuthorizerBase):
"""
Implements a proof-of-stake authorization protocol using Ed25519 keys
Checks the Hypertensor network for nodes `peer_id` is staked.
The ``peer_id`` is retrieved using the Ed25519 public key
"""
def __init__(
self,
local_private_key: Ed25519PrivateKey,
subnet_id: int,
hypertensor: Hypertensor
):
super().__init__()
self._local_private_key = local_private_key
self._local_public_key = local_private_key.get_public_key()
self.subnet_id = subnet_id
self.hypertensor = hypertensor
self.peer_id_to_last_successful_pos: Dict[PeerID, float] = {}
self.pos_success_cooldown = 300
self.peer_id_to_last_failed_pos: Dict[PeerID, float] = {}
self.pos_fail_cooldown: float = 300 # 5 minutes default cooldown
async def get_token(self) -> AccessToken:
token = AccessToken(
username="",
public_key=self._local_public_key.to_bytes(),
expiration_time=str(datetime.now(timezone.utc) + timedelta(minutes=1)),
)
token.signature = self._local_private_key.sign(self._token_to_bytes(token))
return token
@staticmethod
def _token_to_bytes(access_token: AccessToken) -> bytes:
return f"{access_token.username} {access_token.public_key} {access_token.expiration_time}".encode()
async def sign_request(
self, request: AuthorizedRequestBase, service_public_key: Optional[Ed25519PublicKey]
) -> None:
auth = request.auth
local_access_token = await self.get_token()
auth.client_access_token.CopyFrom(local_access_token)
if service_public_key is not None:
auth.service_public_key = service_public_key.to_bytes()
auth.time = get_dht_time()
auth.nonce = secrets.token_bytes(8)
assert auth.signature == b""
auth.signature = self._local_private_key.sign(request.SerializeToString())
_MAX_CLIENT_SERVICER_TIME_DIFF = timedelta(minutes=1)
async def validate_request(self, request: AuthorizedRequestBase) -> bool:
auth = request.auth
# Get public key of signer
try:
client_public_key = Ed25519PublicKey.from_bytes(auth.client_access_token.public_key)
except Exception as e:
logger.debug(f"Failed to get Ed25519 public key from bytes, Err: {e}", exc_info=True)
return False
signature = auth.signature
auth.signature = b""
# Verify signature of the request from signer
if not client_public_key.verify(request.SerializeToString(), signature):
logger.debug("Request has invalid signature")
return False
if auth.service_public_key and auth.service_public_key != self._local_public_key.to_bytes():
logger.debug("Request is generated for a peer with another public key")
return False
# Verify proof of stake
try:
proof_of_stake = self.proof_of_stake(client_public_key)
return proof_of_stake
except Exception as e:
logger.debug("Proof of stake failed, validate request", e, exc_info=True)
return False
async def sign_response(self, response: AuthorizedResponseBase, request: AuthorizedRequestBase) -> None:
auth = response.auth
local_access_token = await self.get_token()
auth.service_access_token.CopyFrom(local_access_token)
# auth.service_access_token.CopyFrom(self._local_public_key)
auth.nonce = request.auth.nonce
assert auth.signature == b""
auth.signature = self._local_private_key.sign(response.SerializeToString())
async def validate_response(self, response: AuthorizedResponseBase, request: AuthorizedRequestBase) -> bool:
auth = response.auth
service_public_key = Ed25519PublicKey.from_bytes(auth.service_access_token.public_key)
signature = auth.signature
auth.signature = b""
if not service_public_key.verify(response.SerializeToString(), signature):
logger.debug("Response has invalid signature")
return False
if auth.nonce != request.auth.nonce:
logger.debug("Response is generated for another request")
return False
try:
proof_of_stake = self.proof_of_stake(service_public_key)
return proof_of_stake
except Exception as e:
logger.debug("Proof of stake failed, validate response", e, exc_info=True)
return False
def get_peer_id_last_success(self, peer_id: PeerID) -> float:
return self.peer_id_to_last_successful_pos.get(peer_id, 0)
def update_peer_id_success(self, peer_id: PeerID):
self.peer_id_to_last_successful_pos[peer_id] = get_dht_time()
self.peer_id_to_last_failed_pos.pop(peer_id, None)
def get_peer_id_last_fail(self, peer_id: PeerID) -> float:
return self.peer_id_to_last_failed_pos.get(peer_id, 0)
def update_peer_id_fail(self, peer_id: PeerID):
self.peer_id_to_last_failed_pos[peer_id] = get_dht_time()
self.peer_id_to_last_successful_pos.pop(peer_id, None)
def proof_of_stake(self, public_key: Ed25519PublicKey) -> bool:
peer_id: Optional[PeerID] = get_ed25519_peer_id(public_key)
if peer_id is None:
return False
now = get_dht_time()
# Recently failed — reject immediately
last_fail = self.get_peer_id_last_fail(peer_id)
if last_fail and now - last_fail < self.pos_fail_cooldown:
return False
# Recent success — no need to check again
last_success = self.get_peer_id_last_success(peer_id)
if last_success and now - last_success < self.pos_success_cooldown:
return True
# On-chain proof of stake check
peer_id_vec = self.to_vec_u8(peer_id.to_base58())
proof_of_stake = self.is_staked(peer_id_vec)
if proof_of_stake:
self.update_peer_id_success(peer_id)
return True
else:
self.update_peer_id_fail(peer_id)
return False
def to_vec_u8(self, string):
"""Get peer_id in Vec<u8> for blockchain"""
return [ord(char) for char in string]
def is_staked(self, peer_id_vector) -> bool:
"""
Each subnet node must be staked
"""
is_staked = self.is_subnet_node_staked(peer_id_vector)
return is_staked
def is_subnet_node_staked(self, peer_id_vector) -> bool:
"""
Uses the Hypertensor `proof_of_stake` RPC method that checks
for a subnet nodes peer_id and bootstrap_peer_id being staked
"""
result = self.hypertensor.proof_of_stake(self.subnet_id, peer_id_vector)
if "result" not in result:
return False
# must be True or False
if result["result"] is not True and result["result"] is not False:
return False
return result["result"]
@property
def local_public_key(self) -> Ed25519PublicKey:
return self._local_public_key
Last updated