Epoch Key

Definition of epoch key in UniRep

Epoch keys are temporary personas which users use them to interact with others.
Instead of giving attestations to an identityCommitment, a random-value-like epochKey is the receiver of an attestation.
Epoch key is computed by

hash(identityNullifier, epoch, nonce) % epochTreeDepth

where nonce and be any value between 0 and numEpochKeyNoncePerEpoch - 1, so that a user can have numEpochKeyNoncePerEpoch epoch keys per epoch.

Only the user knows his identityNullifier so only he knows if he is receiving an attestation, others would see an attestation attesting to a random value.
In the epoch key proof circuit user can prove that he knows the epochKey and can rightfully receive and process the attestations attested to this epochKey.

Epoch Key

Definition of epoch key in UniRep

Epoch keys are temporary personas which users use them to interact with others.
Instead of giving attestations to an identityCommitment, a random-value-like epochKey is the receiver of an attestation.
Epoch key is computed by

hash(identityNullifier, epoch, nonce) % epochTreeDepth

where nonce and be any value between 0 and numEpochKeyNoncePerEpoch - 1, so that a user can have numEpochKeyNoncePerEpoch epoch keys per epoch.

Only the user knows his identityNullifier so only he knows if he is receiving an attestation, others would see an attestation attesting to a random value.
In the epoch key proof circuit user can prove that he knows the epochKey and can rightfully receive and process the attestations attested to this epochKey.