Cross-Chain Messaging System: Problem and Solution

Watch the Demo

Check out our demo video on YouTube. Sorry for the long video, it took time for transaction confirmation. You can see it in 2x speed or more.

Problem Statement

In the rapidly evolving landscape of blockchain technology, there is a growing interest in creating decentralized games that leverage the unique features of different blockchain networks. However, a significant challenge arises when a game developed on one blockchain (referred to as "X" Blockchain) needs to be accessed and played by users on other blockchains (referred to as "A," "B," and "C" Blockchains).

Currently, there is no standardized mechanism for ensuring that users on different blockchains can interact with and play a game created on a separate blockchain seamlessly. This fragmentation limits the game's reach and usability, confining it to users on the original blockchain and preventing wider adoption and engagement.

To address this issue, we propose the development of a cross-chain interoperability solution that allows users on Blockchains A, B, and C to access and play the game created on Blockchain X.

The objective is to design and implement a robust cross-chain relayer system to facilitate secure and efficient message transmission between various blockchain networks. The system will support six testnet blockchains: Theta Network, Sepolia, Arbitrum, Polygon Amoy, Base, and Gnosis Chiado. This relayer network aims to address the complexities of cross-chain communication, ensuring reliable and secure transactions across different blockchain environments. However, several challenges need to be addressed to achieve this goal effectively.

Interoperability Challenges

Cross-chain communication involves interacting with multiple blockchains, each with its own protocol and data structures. This diversity makes it challenging to achieve seamless interoperability between different networks, requiring standardized solutions to facilitate communication.

Security Concerns

Ensuring the security of cross-chain messages is critical. Messages must be protected from unauthorized access and tampering. Without robust security measures, there's a risk of malicious actors intercepting or altering messages, potentially leading to significant vulnerabilities.

Scalability Issues

As the number of cross-chain transactions increases, maintaining system performance and efficiency becomes more challenging. High transaction volumes can lead to bottlenecks and delays if the system is not designed to handle scalability effectively.

Network Fees

Cross-chain transactions often involve multiple network fees, including fees for sending messages and executing transactions on different chains. Managing and minimizing these costs while ensuring efficient transaction processing is a significant challenge.

Solution: Relayer Network

To address these challenges, the proposed solution is a relayer network with the following components:

Relayer Nodes: Multiple nodes listen for cross-chain events from the on-chain contract. They relay these events to the aggregation node, improving scalability and resilience.

Aggregation Node: This node receives messages from relayer nodes, signs transactions, and authorizes them before passing the signed transactions to a randomly selected relayer node.

Selected Relayer Node: The selected node broadcasts the signed transaction to the respective blockchain, ensuring the message is delivered accurately.

The relayer system will comprise multiple decentralized relayer nodes, each responsible for listening to specific events on the source blockchain and triggering corresponding actions on the destination blockchain. These nodes should operate concurrently and independently to ensure scalability and fault tolerance. The system must be capable of handling high transaction volumes and should be designed to minimize latency and optimize performance.

In addition to basic message relaying, the system should include mechanisms for error handling, and logging to ensure transparency and traceability of transactions. It must also provide an interface for monitoring and managing the relayer nodes, enabling administrators to track the status and performance of the relayer network. The design should be flexible to accommodate future enhancements, such as support for additional blockchain networks or advanced message filtering and processing capabilities.

This network architecture enhances security, scalability, and coordination in cross-chain messaging while managing network fees more effectively.

Quicklinks (Order to run app):

• Run the docker-compose file in root dir for mongodb.
• Smart Contracts code Explnation
• Aggregation Node
• Relayers Node
• Game Server
• Game UI
• Sample Game Server
• Sample Game UI

Note:

• During testing, Aggregation node and Relayer node are not running means, cross chain functions won't work, still single chain functionalities continues to work.
• During testing, the game and nfts shown in demo video will not be shown, because, Edge storage node is running locally. So please create new game and new nft items.
• When running Relayer node, there may be a chance of error like 'filter not found error', try to stop that and start again or, anyway it continues to work after sometimes

Testnet Contract Addresses

Testnet	Coupon Address	Contribution Address	NFT Address	Games Address	NFT Lending Address	OffChain Address	FeeCollector Address	OnChain Address	Messaging Address
Gnosis	0xFb1409344A636F6f9d40eE20473743b42Db142D9	0x34ACE2F0cfeB0d3741B7dAC5F013c72cd580cebc	0x3496b0a8809E8a8f2277a7073154fF1e85514c1D	0xb5F68EB4baD78B050DB55DCb02FCC30815B477ea	0x20F1f6104FAC6eA8b38C6f1e0ed06df35716553a	0x66610Ed3C3CfD75d6e49d92AEaf258D9D2FC78DE	0x34072c72Fd0932F327976d55F030E9aD80799329	0xAC0C8Aa0324E4d4ff1170ba4291C17684B4E7ecE	0x00c07E165A65B0132f5FF263363A2FcB80E060aA
Amoy	0xF1b35AE8250eC1901b04b25649db3938F0C8dfe1	0x174Dc96A7Db75119784076f083904Ff531FA2910	0x405cbdbA7C7F006AE9fC5ad952b2d3DDd2aeb0E9	0x07F539B5cCF429EB1490BF404904c066d41b66A4	0x268765515F08E1a9869C07C27eBefD4E69048884	0xC463BD08bb40D9e0a0F3c7B1c9Ad24754BAd8A23	0xAb7b97D145191a3360cbcd6f78f9a99C6b53C23B	0xD88Faf7A4107587d8D9859d5209ce75419482689	0x635Bbb2D4b5fa6eb2D303a2af72624f22cfE7FD4
Arbitrum	0x3A8dd6cD875fFeA174503Bf89Bbd4962643329DD	0xE0bB71aE2445C79eEeaCF540D2503D4819E6e10b	0x0B0B5939eFe118519c1608f31102d7DCbBb42831	0xFA10087fA507dbED5A1e28dD26F1c75BC695cF58	0x0a03B32fB6E71D6c92aCD1BE5c3f0c5C4082545f	0x600EBB34840a167F4a6ab17e32DA899687a3a79a	0x7Bb165B7D69485A520984EE7369d410e8f7260E2	0xe54627cC49699B15698d4D80721d8ea61bFF992e	0xce88047d4F74e94eBB850589eb6b43505e99e8fd
Base	0x82874Aa6db451459739396f3d340E06baf5aDfE6	0x2A48a2504b6831e86A89991Cf71AFD8574f8383e	0x92530cCBA6E15866EE2f9E9df9bBcbeCADeB4243	0xf8974fd417cDcC9d5Cadf61F35228a18D7784bF0	0x495B97AA35dC152C63662640B1A9e34C261f4cda	0xD9A377f073E0DF0BEC7F94Cf718bB7ff5d824A34	0x9D37c91A7bd18EC6f72128D0730e734a792b6377	0x0098b9724C595D76B032a9D5B01b5D1d7Bc34Fb3	0x3A8dd6cD875fFeA174503Bf89Bbd4962643329DD
Sepolia	0xE0bB71aE2445C79eEeaCF540D2503D4819E6e10b	0x0B0B5939eFe118519c1608f31102d7DCbBb42831	0xFA10087fA507dbED5A1e28dD26F1c75BC695cF58	0x0a03B32fB6E71D6c92aCD1BE5c3f0c5C4082545f	0x600EBB34840a167F4a6ab17e32DA899687a3a79a	0x7Bb165B7D69485A520984EE7369d410e8f7260E2	0xe54627cC49699B15698d4D80721d8ea61bFF992e	0xce88047d4F74e94eBB850589eb6b43505e99e8fd	0x64371f372D372315c56C6E09Cb8aC230dc365B48
Theta	0x991Ee2Ad6400e2C7681fa052bEe20900e6368b9D	0x65C525da23480144aB86FeD969Fe121880BdcFBd	0x7FBf88EB6c04faBcbCDC0E1BD96888d7C27353Cc	0x8506FcE859341A2BF20a9d5B62Ea8e6784C2cdC9	0x4650F931A1b0a7B9EA8e8933e5Cc5c1CF260272F	0x3504a02093096D5a6Be2B6Cf38F039613F1eFe6D	0x7a9F0c075DF9D6b94AD61b12BB219F12Ca9c1A68	0xfCDBed330007f3ae4957C7089793CE62f63A87f9	0xD3e01e843FDE41590CDf4ded06A987C353d6aCA1

• Currently our relayer service support 6 blockchains.

Features of Our Applications:

• Mint NFT on same chain as well as target chain.
• Create Game on same chain as well as target chain.
• You can buy both NFT and Game from your own chain without having the target chain crypto, relayer network takes care of that. You can pay the crypto in your own blockchain crypto.
• Relayer network have network fee of 0.0001 of respective blockchain crypto. As of now it is static.
• We can teleport NFT from One blockchain to another blockchain.
• We can rent our NFT on same chain.
• All the assets are stored in Theta Edgestore.
• Livestream our playtime using the Theta livestream feature.
• We have the feautre of recorded video to upload in Theta Video API, so that every users on platform can watch.

About Edge Server:

• Game developers can develop their game and deploy to any other cloud services.
• Theta Game World provides Edge Servers which is used to host games and servers. By Natively, Edge storage have the permanant CDN delivery. We are utilizing that.
• Frontend or Backend .zip files are uploaded to Edge storage, and after that it is running in docker container.

How Relayer Network runs?

• It only runs, whenever there is a strong and flow contribution towards our relayer network.
• Initially, Admin can have some fund to start the nodes. Afterwards, it purely depends on Gaming Community peoples and Game Enthusiasts.
• If they actively participating in the contribution, then the platform can run throughout.
• If Gamers contribute, they will be rewarded with coupons, which can be withdrawable or used to buy the NFTs.
• It is like the Liquidity Market, if liquidity becomes less, then trading will be difficult, likewise, if Contribution becomes nil, then cross chain transaction will be more difficult. But still, same chain functions remain work intact.

Challenges faced:

• Implementing the cross chain relayer is much challenging and I faced lot of challenge to complete.
• Sometimes, we can't send the signed transaction to the Theta blockchain, since it throws error like Transaction already seen with some error code.
• Since, I am running multiple servers, I cannot deploy on the cloud, and I am not much more knowledgeable in cloud part. So, I embedded my private keys into .env files.