Introduction of IOST — Klaytn Crosschain

Sep 30, 2019 · 3 min read

Hello! We’re Second Impact(IOST-Q.E.D), developing blockchain game “Herorats.”

The blockchain used in the “Herorats” game is an IOST blockchain! There were three reasons why we chose IOST blockchain. The first was “fast block time,” the second was “low resource fees,” and the third was the development of Smart Contract with Javascript, the language most familiar to developers.

Problem: IOST DApp can only be played by IOST users.

But the limit that I felt after making Dapp with IOST was that only IOST users can play, and developers can only get IOST out of so many cryptocurrency. Although we developed a DApp using the IOST blockchain, we hoped that in addition to IOST users, other blockchain platform users would be able to play our games. Of course, it’s also important to receive multiple cryptocurrencies in the process!

So the first thing we thought of as a solution was token swap. Token swap refers to taking an ETH from a user who has an ETH and issuing an “iETH” that is considered an ETH in the IOST blockchain world and giving that iETH to the user. This is convenient because Etherium users can run IOST’s DApp without having to go through the exchange.

But the premise of this token swap is that Ethereum users must also have an IOST wallet to receive the iETH. Users who are really interested in blockchain may have multiple platforms of wallets, but most blockchain users usually have only one blockchain wallet.

Our Solution: Crosschain

The solution we came up with was “Crosschain”.
In Crosschain, which we developed, we have a special account called “mediator.” This “mediator” is able to receive requests from users of other blockchain platforms and call the IOST blockchain’s Contract function instead of the user.

Klaytn — IOST Crosschain

Here’s a brief schematic of Crosschain! Don’t worry, I’ll post an easy-to-speak posting soon!

Anyway, this Crosschain will allow many blockchain platform users to use the IOST blockchain’s DApp, which will improve the IOST blockchain ecosystem!

IOST — Klaytn Crosschain Demonstration Video

We talked too long, didn’t we?

The first blockchain platform we connected through Crosschain is the Klaytn. Klaytn is a blockchain platform developed by Ground X, a subsidiary of Kakao, which developed the most popular messenger app in Korea, and is currently receiving high expectations in Korea.

Below is a video clip that connects Klaytn through crosschain to our game Herorats!

If you look at each of the elements in the video,
1) Klaytn user pays 1 KLAY through chromium extension and asks to purchase the banana, which is Herorats’ game item.
2) Crosschain observes the Klaytn blockchain world and detects that a banana purchase request has been made.
3) Receive detected “Banana Purchase Request” data to determine where to send the request within the IOST blockchain. (Herorats IOST contract address)
4) A special account, “mediator,” performs the request instead. (Contract call)
5) Check if any problems have occurred in Step 4.
5–1) If Step 4 did not cause any problems, then the Crosschain operation was successful!
5–2) Crosschain will refund 1 KLAY to Klaytn users if the target address is incorrect or if a contact function call has failed.

We’ll post in another post on how this technology works and what the technical limitations are!

+Klaytn Testnet is used in this demo version. As soon as KLAY is listed on the Korean exchange, wewill connect to Klaytn Mainnet and launch the beta version of Crosschain!

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Herorats Game:




Second Impact


Written by

software engineer, blockchain

Second Impact

Make an impact with blockchain

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