One of the fascinating aspects of crypto is that there are numerous blockchains but they do not cooperate. Bitcoin, Ethereum and Solana are examples of such independent networks with their own rules of transaction processing. Diversity of blockchain networks provides more freedom to choose, but at the same time it makes the transition of digital assets from one blockchain to another difficult.

For instance, a person who has ETH assets in the Ethereum network cannot transfer his/her coins to the Solana network because of the difference in operations within separate networks. It means that he/she will not be able to use the application in the Solana network transferring his/her ETH directly to the Solana wallet.

Bridges are developed for transfer or issuance of representation of assets on another network. This process can be realized in different ways depending on the particular bridge and involves either locking assets in one network and creating corresponding tokens in another network, or any other mechanism for transferring them.

It should be noted that bridged token does not necessary have to be equivalent to the original asset in the native network.

Perhaps the main problem associated with crypto asset transfers between blockchains is security. The bridge needs to check the fact of an event on one network and then let it happen on another. Each bridge has a specific solution to the task and its own level of security depending on the solution used.

For example, some bridges depend on validators or other participants in the chain for asset transfers, and some bridges use smart contracts and cryptographic checks. In case of any vulnerabilities or attacks on the verification system, attackers can steal money or mint unbacked tokens. There were several major crypto hacks that were connected with the vulnerabilities in cross-chain bridges.

But there is also a problem with usability. For example, users need to know which blockchain they are on and whether the asset is native or bridged. They also need to be aware of potential fees and time delay. Any mistake will be hard to correct since users will transfer funds through the unsupported route.

There are some projects that work on solving this problem. But there is no way to make all the blockchains fully compatible.