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Enhancing Bitcoin Interoperability with MAP Protocol

MAP protocol is a Bitcoin scaling solution that enables communication between different blockchains.
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Bitcoin disrupted the world when it introduced blockchain technology in 2008. People could send value across the globe without intermediaries for the first time. However, Bitcoin and other early blockchains were limited to their isolated ecosystems due to a lack of interoperability, constraining innovation.

Now, a new solution is poised to unlock more potential of the Bitcoin blockchain - MAP Protocol. By enabling communication between different blockchains, MAP Protocol paves the way for seamless asset transfers, cross-chain smart contracts, and an open blockchain ecosystem.

What is MAP Protocol?

MAP Protocol is a decentralized interoperability protocol leveraging omnichain infrastructure, built on light clients, zero knowledge (ZK) technology, and leverages its novel BRC-201 token standard. It adopts the Simplified Payment Verification (SPV) light client defined by Satoshi Nakamoto. 

But what are light clients? In short, ​​a light client enables applications, devices, or other blockchains to interact with a blockchain efficiently and securely without downloading the entire blockchain state. 

Understanding MAP Protocol’s Three-Layer Architecture

The MAP Protocol can be broken down into three layers: the Protocol Layer, the MAP Ominchain Service Layer, and the Application Layer. Below, we'll dive into the importance of each and how they collectively achieve cross-chain interoperability with heterogeneous blockchains.

Protocol layer

MAP Protocol's core is responsible for peer-to-peer cross-chain communication and transaction verification. It comprises the MAP Relay Chain, Maintainer, and ZK-optimized light clients.

MAP Relay Chain

The MAP Relay Chain is a blockchain-based on the Proof of Stake (PoS) consensus mechanism and implements the Istanbul Byzantine Fault Tolerance (IBFT) consensus algorithm. Validator nodes must stake MAPO, MAP Protocol’s native token, to process cross-chain transactions on the MAP Protocol network.

The relay chain features a virtual machine (VM) similar to Ethereum, making MAP Protocol EVM-compatible. However, a unique attribute is its pre-compiled contracts, embedded with most blockchains' core signature and hashing algorithms, enabling cross-chain interoperable transaction requests to pass through the relay chain.

Algorithms already integrated with the MAP Protocol include: SHA3, SHA-256, Ed25519, Secp256k1, Keccak-256, Sr25519, and Blake2b.

Source: MAPO

At the end of each epoch, the MAP Relay Chain records its block hash and writes it into the most recent Bitcoin block. This check-pointing mechanism enables the relay chain to prevent long-range attacks while inheriting the security of the Bitcoin network.


These are a group of off-chain roles responsible for updating the latest block headers and Merkle tree proofs from the origin chain’s consensus layer to the light client smart contract deployed on the target chain. These light client updates are transactions written to the chain, incurring gas fees to the Maintainer.

After verifying the light client smart contract state, maintainers can no longer tamper with its block headers or Merkle tree proofs, preventing any malicious attacks. To run a MAP Maintainer, users need to meet hardware and staking requirements, along with the financial resources necessary to prepay gas fees on the target chain.

ZK-Optimized Light Clients

Optimizing peer-to-peer cross-chain verification with refactored light clients, MAP Protocol circumvents higher transaction costs associated with existing cross-chain solutions, many of which rely on intermediaries.

MAP Protocol light clients are deployed on the smart contracts of target chains to ensure secure and accurate cross-chain interactions. The light clients are tailored to the specific consensus mechanism of the origin chain, whether PoS or PoW. Due to differences in each consensus’ block header categories, the light client implementations operate as follows:

Origin Chain Light Client (PoS)

The light client of an origin chain deployed on a target chain's smart contract adjusts to changes in the validator set of the origin chain. This takes place when Maintainers update the target chain's light client by recording the validator set's BLS aggregate signature, voting weights, and public keys.

Maintainers require approval from the previous validator committee's signature to ensure these updates are authentic. This system prevents the acceptance of false information unless there's a significant compromise of the origin chain or alteration of the smart contract.

Origin Chain Light Client (PoW)

In PoW chains, the light client on the target chain gets updated with the latest block header from the origin chain. Maintainers perform this task, and the light client's smart contract checks this new information against the previous block header's hash values to verify its accuracy. This step is crucial to block any false data from being recorded.

MAP Omnichain Service (MOS) Layer

The MAP Omnichain Service (MOS) Layer functions similarly to an SDK, offering developers a suite of tools designed to streamline the development and deployment of cross-chain smart contract applications and their accompanying messaging protocols.

Messenger operators are vital in facilitating communication between light clients, and must prepay gas fees on the relay and target chains. Due to the unpredictability of target chain fees, this MOS layer grants developers the flexibility to incentivize Messenger operators through rewards and fee standards.

Application Layer

Lastly, this layer is where most users will interact with various decentralized omnichain applications. Applications like DeFi lending, NFT marketplaces, gaming, AMMs, oracles, and decentralized exchanges can leverage unified liquidity and interoperate here.

Token Supply and Usage

This token distribution strategically supports block generation, network maintenance, ecosystem development, and community growth within the MAP Protocol network. Here’s a breakdown of the token allocation:

  • Developers (Team) of MAP Protocol are allocated 15 million tokens, with a vesting period from 2019 to 2025.
  • The Ecosystem DAO receives 21 million tokens, which are not locked and are governed entirely by the decisions of the MAPO Community. Ensuring decisions are democratically decided through discussions on the MAP forum and on-chain voting, particularly for decisions impacting community members.
  • The MAP Foundation has a 12 million token allocation focused on establishing the initial stage of the MAP Protocol ecosystem and the broader web3 omnichannel ecosystem, setting the foundation for a fully decentralized future.
  • Investors and early supporters have a 22 million token allocation, acknowledging their crucial role and support in the early stages of the MAP Protocol.
  • Mining rewards have 30 million tokens earmarked for Validators on the MAP Relay Chain and Maintainers, incentivizing the maintenance and security of the network.

This distribution model reflects MAP Protocol's commitment to a balanced, inclusive, and growth-oriented ecosystem, ensuring all key contributors are appropriately incentivized.

Vested tokens and those already in circulation are eligible for staking. This means that staked vested tokens also benefit from staking rewards distributed during each Epoch. By the end of 2038, all MAPO tokens will be mined, unlocked, and fully circulated.

BRC-201 Token Standard

The MAP Protocol community released the BRC-201 protocol that enables cross-chain functionality of BRC-20 and ORC-20 assets. This development could vastly improve the accessibility and liquidity of BRC-20 and ORC-20 tokens on Bitcoin expanding to other blockchains.


The MAP Protocol is a unique Bitcoin scaling solution and a comprehensive ecosystem designed for secure and efficient cross-chain communication and application development. MAP Protocol inherits security from the Bitcoin blockchain through checkpointing, building on its trust-minimized architecture. 

By connecting EVM and non-EVM chains using light client verification with pre-compiled contracts embedded with various blockchain signatures and algorithms, it is evident that MAP Protocol is committed to interoperability and unifying different blockchains. Additionally, its introduction of the BRC-201 protocol is an exciting development, potentially expanding the ability to bring BRC-20 and ORC-20 tokens into other ecosystems.