# System Parachains

**System Parachain** includes essential ***InfraBlockchain*** protocol functionalities, but these functionalities reside in the parachains rather than Relay Chain. By hosting core protocol logic in parachains instead of Relay Chain, ***InfraBlockchain*** utilizes its self-hosting capability through parallel execution, a unique extension technology. The System Parachain removes transactions performing protocol functions from Relay Chain, allowing the [Blockspace](https://docs.infrablockchain.net/infrablockchain-docs/infrablockchain/learn/architecture#block-space) to be more dedicated to its core functionalities (e.g. [parachain validity verification](https://docs.infrablockchain.net/infrablockchain-docs/infrablockchain/learn/architecture#parachain-state-transition)).

The governance of the System Parachain is conducted by Relay Chain and serves as a special parachain for the entire ***InfraBlockchain*** network. The System Parachains within ***InfraBlockchain*** include:

* [**Asset Hub**](#asset-hub): A system chain governing functionalities related to tokens (e.g. [System Token](https://docs.infrablockchain.net/infrablockchain-docs/infrablockchain/learn/protocol/system-token)).
* [**Bridge Hub**](#bridge-hub): A system chain overseeing bridges between different networks.

### Asset Hub

#### Overview

***Asset Hub*** is a system chain within the ***InfraBlockchain*** ecosystem responsible for governing functionalities related to tokens (e.g. [System Token](https://docs.infrablockchain.net/infrablockchain-docs/infrablockchain/learn/protocol/system-token)). It assists token issuers (e.g. System Token issuer) in generating tokens within the ***InfraBlockchain*** network, tracking the total token supply (including tokens[ transferred to other parachains](https://docs.infrablockchain.net/infrablockchain-docs/infrablockchain/tutorials/build/transfer-assets-with-xcm)). Additionally, it facilitates the creation, minting, and burning of on-chain assets, managing on-chain assets deposited and created in accordance with [Uniques Pallet](https://github.com/InfraBlockchain/infrablockchain-substrate/tree/822bc6c9706774a98122eb432f412b871a98a4bd/substrate/frame/uniques) and the new [NFTs Pallet](https://github.com/InfraBlockchain/infrablockchain-substrate/tree/822bc6c9706774a98122eb432f412b871a98a4bd/substrate/frame/nfts).

Since the token-related logic is executed directly in the runtime rather than through smart contracts, the cost of executing transactions in parachains is approximately 1/10 of that on Relay Chain. This low fee level implies that **Asset Hub is well-suited for handling system token balances and transfers, as well as managing on-chain assets across the network.**

### Bridge Hub

**Bridge Hub** is a system chain responsible for functionalities related to bridging in the context of building a ***Federated Multi-BlockChain***, where multiple ***InfraBlockchain*** ecosystems are interconnected.