NCNs

An overview of the Node Consensus Network (NCN) component.

Overview

A Node Consensus Network (NCN) is a decentralized service or network that reaches onchain consensus on offchain data or workloads. This may include oracles, DePIN services, bridges, co-processors, or new chains. NCNs represent one of the core components in the Jito Restaking ecosystem, alongside Operators and Vaults.

It is one of typical NCN design (On-Chain NCN Program), so every NCN does not have to follow this design.

Key functionalities include:

Authority Management: Designate and validate admins for various NCN operations
Operator and Vault Tracking: Manage relationships with operators and vaults through mutual opt-in mechanisms
Consensus Coordination: Facilitate onchain consensus on offchain execution results
Reward Distribution: Calculate and distribute rewards to participating operators, vaults and stakers
Asset Weight Management: Define supported tokens and their respective weights in the network

On-Chain NCN Program Components

NCN consists of several key components that work together to provide decentralized services:

Pricing

Defines supported tokens and their respective weights in the network, determining how different assets are valued within the NCN ecosystem
Manages token weight tables that influence voting power and reward distribution
Controlled by the weight_table_admin role

Snapshot

Captures the current state of Vaults, Operators, and Operator Stake Weights at specific intervals to establish consensus baselines
Creates a frozen, point-in-time view of the network's state for consistent voting
Includes EpochSnapshot accounts to track total stake weight and participant counts
Records individual OperatorSnapshot accounts for each operator's delegated stake weights

Core Logic

Implements the fundamental consensus mechanisms that govern how nodes participate and validate output within the network
Handles vote tallying and determines when consensus thresholds are reached
Manages epoch transitions and consensus finalization
Defines slashing conditions and enforcement logic

Reward Payments

Manages how rewards are calculated and distributed to participating operators, vaults and stakers based on their contributions to the network
Implements stake-weighted reward distribution mechanisms
Handles fee collection and distribution according to NCN-specific logic
Coordinates with the restaking program for reward processing

Key Components

1. NCN Structure

The NCN account structure is designed to handle various administrative and operational roles within the network:

Field	Type	Description
base	Pubkey	The base account used as a PDA seed.
admin	Pubkey	Overall administrator of the NCN.
operator_admin	Pubkey	Admin responsible for managing operators.
vault_admin	Pubkey	Admin responsible for managing vaults.
slasher_admin	Pubkey	Admin responsible for managing slashers.
delegate_admin	Pubkey	Admin for delegating assets of NCN account.
metadata_admin	Pubkey	Admin responsible for NCN metadata updates.
weight_table_admin	Pubkey	Admin for managing asset weight tables.
ncn_program_admin	Pubkey	Admin for on-chain programs associated with the NCN.
index	u64	Index of the NCN account.
operator_count	u64	Number of operators registered with the NCN.
vault_count	u64	Number of vaults registered with the NCN.
slasher_count	u64	Number of slashers registered with the NCN.

Finding NCN PDA

use jito_restaking_core::ncn::Ncn;

let program_id = jito_restaking_program::id();
let base_pubkey = pubkey!("base pubkey here");
let ncn_pubkey = Ncn::find_program_address(&program_id, &base_pubkey).0;

Node Operator Client

The Node Operator Client represents the core off-chain logic of the NCN. This is where the actual work and computation happens that the NCN is designed to coordinate and secure.

Key characteristics:

Runs arbitrary computation as defined by the NCN's specific requirements
Posts data on-chain through custom instructions
Signs transactions using the operator keypair
Executes the offchain services that the NCN was designed to provide

Sample Node Operator Clients:

Tip Router Operator Client - Handles tip routing calculations and submissions
Solana Merkle Root Uploader - Uploads merkle roots for tip distribution
Stakenet Keeper - Manages stakenet operations and state transitions

Permissionless Cranker

For all of the permissionless operations that need to occur on a regular cycle, NCNs require a client that continually executes instructions to maintain network health and progression.

Functions include:

Triggering epoch transitions and snapshots
Processing routine maintenance operations
Executing time-sensitive consensus operations
Managing account cleanup and optimization

Sample Permissionless Cranker:

Jito Tip Router Keeper - Automated keeper for tip router operations

NCN Operation Cycle

NCNs operate in continuous cycles that involve:

Setup Phase: Establishing relationships with operators and vaults through mutual opt-in
Snapshot Phase: Capturing network state for consistent consensus baselines
Execution Phase: Operators perform offchain work and submit results
Consensus Phase: Onchain vote tallying and consensus determination
Reward Phase: Distribution of rewards based on performance and stake weights
Maintenance Phase: Account cleanup and network parameter updates