Interoperability Between Blockchains
How different blockchain networks communicate and exchange value, and the common approaches.
What to remember
- Interoperability lets otherwise-independent blockchains exchange information or value.
- Bridges, atomic swaps, and purpose-built interoperability protocols are common approaches.
- Each approach makes distinct trust and security trade-offs.
- Interoperability mechanisms add their own risk layer on top of the underlying chains' risk.
Why interoperability is needed
Different blockchains generally operate as independent, self-contained systems with no native way to communicate. Interoperability refers to the various techniques developed to let separate blockchains exchange information or value with each other.
Common approaches
- Bridges: lock an asset on one chain and mint a representative wrapped version on another.
- Atomic swaps: a trustless, direct exchange between two chains using cryptographic techniques.
- Interoperability protocols: purpose-built messaging systems (such as the Inter-Blockchain Communication protocol used across the Cosmos ecosystem) that let connected chains pass verified messages to each other.
Real trade-offs
Each approach makes different trust and security trade-offs — a bridge, for example, introduces trust in the bridge's own security, separate from the security of either connected chain, and bridges have been a frequent, well-documented target for exploits.
"Connected" doesn't mean "equally secure"
An asset moved via a bridge or interoperability protocol takes on that mechanism's own security assumptions, in addition to whatever risk the original asset and chain already carried.
What to remember
- Interoperability lets otherwise-independent blockchains exchange information or value.
- Bridges, atomic swaps, and purpose-built interoperability protocols are common approaches.
- Each approach makes distinct trust and security trade-offs.
- Interoperability mechanisms add their own risk layer on top of the underlying chains' risk.