Validator Key Sharing

How operator validators are paired with AVS nodes

One of the key aspects of Cambrian's infrastructure is the ability to launch additional machines for AVS validation alongside the primary Solana node using a single private key. Cambrian's implementation will resemble DVT and will comprise the following com-ponents:

• Shamir's secret sharing - Validators (main node and AVS) use BLS keys. Individual BLS "key shares" can be combined into a single aggregated key (signature). The private key for a validator is the combined BLS signature of each node (Solana node and AVS nodes) in the validator cluster.

• Distributed Key Generation (DKG) - A cryptographic process that generates key shares and is used to distribute shares of an existing or new validator key between Cambrian nodes (Solana node and AVS nodes).

• Multiparty Computation (MPC) - the full validator key is generated in secret using multiparty computation. The full key can be known to the validator if it keeps control of both the Solana node and AVS nodes. Or the key may not be known to any operator if there are multiple individuals in the AVS cluster, but there is one common Solana node - they will only know their part of the key (their "share").

• The next component in the case of DVT is a consensus protocol that governs the relationship of nodes in individual clusters - the consensus protocol selects one node as the initiator of a block. It passes the block to other nodes in the cluster who add their key shares to the common signature. In the case of Cambrian, this separate consensus mechanism can be implemented within AVS if there are multiple individuals in the cluster.

• Mechanism of calculation and distribution of rewards between different AVS of one validator depending on its stability of work, distribution conditions from AVS themselves. This may also require an atomic swap or wrapped token mechanism, as different AVSs may have different token standards depending on the VM used.