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Wanchain’s upcoming Mercury hard fork upgrade hits the testnet

Make sure to upgrade your GWAN client!

Following the hard fork upgrade dedicated to Galaxy Consensus in late August this year, Wanchain will be undergoing another hard fork upgrade codenamed Mercury in the coming days.

This hard fork upgrade named Mercury is scheduled to occur on December 16 2019 at 0:00 UTC on the Wanchain testnet. When the Epoch ID of Galaxy Consensus reaches 18246, all Wanchain GWAN clients on the testnet which has been updated prior to that date will smoothly switch to the new Mercury branch.

In order to ensure the normal syncing process after a hard fork, all validators and all users running GWAN on Wanchain testnet should update their GWAN client to the latest version before December 16, 2019 0:00 AM UTC.

How to update the GWAN client

For updating of the GWAN client, you can choose between updating using scripts or a manual update.

1) Update testnet GWAN using scripts:

We have prepared easy to use scripts for updating GWAN client. Users who have deployed GWAN using scripts, can log in to their server through SSH protocol then execute following instructions:

$ rm updateValidator.sh$ wget https://raw.githubusercontent.com/wanchain/go-wanchain/develop/loadScript/updateValidator.sh && chmod +x updateValidator.sh && ./updateValidator.sh

(Further details about Wanchain PoS scripts can be found here:https://www.explorewanchain.org/#/staking/pos-scripts)

2) Update manually testnet GWAN:

In a customized operating environment, users can manually download GWAN binary version 2.1.4-beta through the link below, and update GWAN client by replacing current one with the newer version:


What’s new in the Mercury upgrade?

The Mercury upgrade will bring two long awaited important features/feature upgrades:

1) Smart Contract API for Safe Random Numbers

2) Raising blocks’ standard gas limit

These 2 new features/upgrades are essential for promoting Wanchain’s ecosystem, increasing Wanchain’s developer friendliness, and promoting new development path of DAPPs. They are detailed in the following:

1) Smart Contract API for Safe Random Numbers

One of key innovation in Wanchain’s Galaxy Consensus is Safe Multi-Party Random Number Generation. It periodically generates a group of random numbers on the blockchain through Galaxy Consensus Protocol. This random number is a true random number that is unbiased, unpredictable, and evenly distributed within its range.

Safe Random Numbers lay the foundation for all blockchain based gaming DAPPs. A truly unpredictable, unbiased (cannot be manipulated by anyone, even miners) random number serves as a safeguard for gaming DAPPs, it can guarantee the fairness and trustworthiness of a game, preventing insider trading and all kinds of hacking attempts.

By opening an API for Smart Contract deployed on the blockchain, DAPPs can be operated in a fully decentralized way. It takes only a front-end web page plus a Smart Contract on Wanchain to build a fully functional gaming DAPP.

Prior to implementation of a true random number, gaming DAPPs mostly rely on block hashes, transaction hashes, or external oracles as sources of randomness. Block hashes and transaction hashes are vulnerable to manipulation by miners and stakeholders, external oracles on the other hand, tend to rely on availability and trustworthiness of a centralized source of randomness. Neither of them can provide both fairness and reliability in a decentralized way, they can merely raise barriers to wrongdoing.

The API for Safe Random Numbers introduced by Wanchain’s Mercury upgrade can provide a source of decentralized true random numbers which can’t be manipulated by miners or individuals. Additionally a Smart Contract API can drastically simplify the amount of development effort and server costs required to provide randomness.

It empowers fully decentralized, serverless DAPPs and makes them a reality — the key take-away of this new API.

2) Raising blocks’ standard gas limit

With the Mercury upgrade, blocks’ default gas limit have been increased from 4.7M to 10M on Wanchain.

This increase greatly improves the development experience of large scale DAPPs on Wanchain and removes the constant need to break down smart contracts in order to fit them on the block due to a low gas limit.

Smart contracts written in Solidity on other blockchain platforms can now be migrated to Wanchain with greater ease, allowing developers to focus more on Wanchain and leverage its unique features, bringing more DAPPs of higher quality to Wanchain.

This upgrade also raises Wanchain’s instantaneous TPS, paving a quick path of data for future DeFi DAPPs to take, improving the efficiency of transactions.

Therefore, the higher gas limit included in Wanchain’s Mercury upgrade will bring benefits for all sorts of applications.

If the Mercury upgrade and hard fork on Wanchain’s testnet goes smoothly, Wanchain’s mainnet will also undergo this upgrade in the coming days.

So, to all validators and all parties running the GWAN node: please pay attention to Wanchain’s future announcements.

Thanks for your support for Wanchain and its decentralized cross-chain mechanism, looking forward to a bright future for blockchain and open finance!

About Wanchain

Wanchain is a blockchain platform that enables decentralized transfer of value between blockchains. The Wanchain infrastructure enables the creation of distributed financial applications for individuals and organizations. Wanchain currently enables cross-chain transactions with Ethereum, and today’s product launch will enable the same functionalities with Bitcoin. Going forward, we will continue to bridge blockchains and bring cross-chain finance functionality to companies in the industry. Wanchain has employees globally with offices in Beijing (China), Austin (USA), and London (UK). Website | Documentation | Telegram| Twitter | Newsletter | Blockchain Explorer | Developer Portal



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