January 27, 2023

What is IBC?

The Inter-Blockchain Communication protocol allows different blockchains to communicate with each other without introducing any additional trust assumptions.
By AJ Scolaro


Blockchains are sovereign systems are not compatible with each other by default. Bridges are tools used to allow crypto users to transfer the value associated with a token from one chain onto another chain. Bridges don’t actually transfer tokens across blockchains, but rather lock a token on its native blockchain and mint or unlock a “wrapped” representation of the token on the destination blockchain. When a user wants to regain access to their tokens on the original blockchain the bridge relocks, or burns, the wrapped tokens and unlocks the tokens on the original blockchain.

Since many blockchains weren’t built with interoperability in mind from day one, bridges are often vulnerable to attacks and unreliable for users.



In the current version of the internet the “Transmission Control Protocol” (TCP) is used as a communication standard to allow devices and programs to share data over a network, and the “Internet Protocol” (IP) is used to determine where the data is delivered. TCP and IP work together to organize, authenticate, and transport data between devices. In other words, the TCP/IP model is what permits the communication of information on the internet. TCP/IP is widely used because of its reliability for users and simplicity for developers.

The Inter-Blockchain Communication Protocol, or IBC, can be thought of as the TCP/IP model for web3. IBC provides the communication standard needed for blockchains to securely order, authenticate, and transport data between each other in a decentralized manner. 

Another way to think about IBC is to think of it as a postal service for blockchains. Similarly to how a postal service is solely responsible for the delivery of mail from one place to another and doesn’t control or know the contents of the mail being delivered, IBC is responsible for the secure transfer of data packets between IBC-enabled blockchains and doesn’t limit what type of data can be transferred or know what the data being transferred represents.

How Does it Work?

When a user uses the IBC to transfer value between blockchains, tokens are first locked up on their native blockchain. Next, the native blockchain shows the destination chain the exact amount of tokens that are locked up. Once the destination chain verifies for itself that the information being transmitted is correct, it mints tokens to represent the value associated with the locked tokens on the original blockchain. While the actual token being transferred never actually leaves its native blockchain, the value associated with it does. From a user’s perspective, tokens are transferred from one blockchain and received on another in a matter of seconds.

When a user wishes to transfer tokens back from the destination blockchain to the native blockchain, the tokens that represent the native tokens are burned on the destination chain and the native tokens are unlocked on the original blockchain. Once again, from a user’s perspective the tokens are simply transferred from the destination blockchain and received on the native blockchain within seconds.

It’s important to note that IBC simply transfers data between blockchains. It is up to the destination blockchain to make use of the data provided.

What Makes the IBC Unique?

The IBC offers simplicity and flexibility that is unrivaled by other cross-chain communication protocols. The IBC allows data to be ordered, authenticated, and transferred between blockchains, but doesn’t set boundaries for what the data is or how it needs to be structured. This makes the IBC an attractive interoperability solution for developers who want their products to be as accessible as possible. When a blockchain enables the IBC, users of the greater crypto ecosystem are able to easily access the products and services built on the blockchain, and the blockchain’s pre-existing users are able to easily access all other IBC enabled blockchains. 

In addition to simplicity and flexibility for builders, the IBC offers the highest levels of safety for users looking to transfer value between chains. If an IBC transfer fails for any reason, data is not lost but rather returned to the blockchain that initiated the transfer. This means that those who use the IBC to transfer value between chains don’t have to worry about the potential loss of assets. The relayers that facilitate the transfer of data between blockchains are both permissionless and trustless so users have no need to fear a centralized bridge failure. If a relayer isn't working as intended, anyone can spin up and deploy a new one.

With the IBC, data can easily be transferred between its native chain and any IBC-enabled destination chain. Data that exists on a destination chain cannot be transferred to another destination chain without first going back through the native chain. This helps serve as a security mechanism to ensure that if one chain is compromised, the rippling effects can be minimized.


Take the Quiz


Badges serve as proof a user has completed the corresponding Umeeversity Quiz. Badge owners should not expect to receive any UMEE tokens or additional rewards.