IBC Outside of Cosmos: The Transport Layer

Key Insights

• Inter-Blockchain Communication Protocol (IBC) is a battle-tested messaging protocol that has been successful in the Cosmos ecosystem, but its adoption outside of Cosmos has been limited.
• Building a bridge involves tradeoffs between trustlessness, general message passing, and compatibility. A modular approach allows bridge developers to focus on a few components and effectively let apps customize their end bridge stack.
• Polymer aims to standardize IBC as the transport layer for the multichain world, where apps can achieve true composability and optimized user experiences across chains.

Connecting separate blockchains is one of the major issues within crypto as disparate tech stacks do not natively communicate. The major hangup is connecting blockchains and moving assets across them without needing to trust third parties for secure communication. Since different blockchains have different tech stacks, there currently doesn't exist a universal solution that doesn't make some compromise.

The tradeoff is known as the messaging bridge trilemma. Any given bridge can only sufficiently guarantee two out of three of the following characteristics: decentralization, the ability to be used by any chain, and passing arbitrary data. Builders have started to focus on bridges with the fewest trust assumptions, which is key in preserving bridge security as multiple bridge exploits have transpired in the last year alone.