Interoperable

Substrate-based blockchain networks have the choice of either operating as a solo chain, a solo chain with a bridge, or to integrate as a parachain. Integrating as a parachain enables independent Substrate-based blockchains to gain interoperability with the other independent blockchains. The secret sauce of parachain interoperability lies in XCMP (Cross-Chain Message Passing). XCMP enables parachains to share trusted logic, for example, transferring tokens between networks, without any additional trust assumptions!

Blockchain networks that are not parachains, such as Ethereum, are accessible through parachain bridges. By becoming a parachain on networks such as Polkadot or Kusama, your Substrate-based blockchain also gains interoperability with major blockchains such as Bitcoin and Ethereum while gaining pooled security.

Compute and storage come at a cost in any system, even more so with blockchain networks since many nodes perform the same computation and store many copies of the data. Often the concept of "gas" is introduced because of computational resource limitations. Because of Substrate’s modularity, gas is completely optional, and the introduction of off-chain features greatly reduces computation and storage costs.

Off-chain features run in their own execution environment outside of the Substrate runtime. This creates a separation of concerns and ensures block production is not impacted by long-running off-chain tasks.

With Substrate you're not only free to choose your parameters such gas costs, governance, and consensus, you're also free to choose how your blockchain is deployed and if/how it should communicate with other networks. This means your chain can operate completely independently or connect to networks such as Polkadot to gain greater security and interoperability.