# Bridging

There are inherent flexibility issues with **native** and **application-specific** chains when compared to traditional EVM chains. An application-specific chain is limited as it can not support a complete service that involves interaction between more than one application. Those problems could heavily damage the reputation of a project built on them.

Our solution to this issue is to allow AppLayer-enabled blockchains to natively communicate with each other by using the Chain Abstraction Network (hereby denominated **CAN**) as a middleman, where AppLayer serves as an intermediary between two dApp chains trying to communicate with each other. We call that **bridging**.

It's possible to bridge *arbitrary data* and *tokens*, both *between AppLayer nodes* and *between AppLayer and external networks*.

## How is safety ensured?

The Validator and Sentinel nodes that read from a given chain are determined using RandomGen, the trustless decentralized randomness generator developed by AppLayer Labs. We ensure to keep a fair selection of nodes, however, there is a possibility of a 51% attack.

For example, in a network with 100 nodes, if a malicious user controls 51 of them, and all of them get selected for driving a cross-chain request and a block, they could collude and forward any message they want.

We avoid this by introducing Sentinels to the network. Sentinels are AppLayer Labs-powered Validators that ensure this collusion does not happen. Sentinels can not create new blocks, but rather work together with Validators to fortify the network’s security.