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Ethereum [ETH] hardfork: Goodbye Constantinople, Hello Istanbul!


ambcrypto.com 05 March 2019 05:10, UTC
Reading time: ~4 m

Ethereum [ETH], the cryptocurrency second only to Bitcoin and a leading smart contract platform, has always been one of the most talked about projects in the crypto-space since it was introduced by Vitalik Buterin. Over the past few years, the project has marked several milestones, both in terms of development and adoption.

The potential of the project was also recognized by several key players within the cryptocurrency space. Notably, among them was Roger Ver, Founder of Bitcoin.com, formerly nicknamed “Bitcoin Jesus.”

According to reports, Ver had stated that Ethereum could “overtake” Bitcoin by the end of 2018. In the meantime however, the bear market took control of the cryptocurrency market, which led to the world’s second largest cryptocurrency closing the year with a loss of around 90% of its value.

Nonetheless, the project always stood out for its technical advancements, especially with all the buzz surrounding the platform’s shift to Proof-of-Stake [PoS] consensus mechanism.

The upgrade was in the spotlight during the recent Ethereum Devcon, with Vitalik giving a brief introduction to Ethereum 2.0. Based on the roadmap, to get to the final phase, Ethereum would have to first complete the first three phases: Frontier, Homestead, and Metropolis. The first two phases were checked out by the Ethereum Foundation a long time ago.


Unlike the first two phases of Ethereum – Frontier and Homestead – Metropolis was divided into two: Byzantium hardfork and Constantinople hardfork. According to the official blog post, this phase is “when we [EF] finally release a relatively full-featured user interface for non-technical users of Ethereum”.

Byzantium hardfork was one of the smoother upgrades and introduced eight Ethereum Improvement Protocols [EIP]s. All of these protocols went live in October 2017 on block #4,370,000. The key feature of the upgrade was the delay of the difficulty bomb, reducing the block reward from 5ETH to 3ETH.

However, Constantinople, the second half of Metropolis, faced several hurdles, with the fork being pushed to a further date twice. This upgrade was also one of the most-awaited in the Ethereum community. The initial proposal for the upgrade consisted of five Ethereum Improvement Protocols, with the main spotlight again on the delay of the difficulty bomb and the thirdening – reduction of the block rewards further from 3ETH to 2ETH.

The first time the upgrade was delayed, it was due to issues faced during the Ropsten Testnet Constantinople hardfork. The second was when it was discovered that one of the proposed improvement protocols made way for a Reentrancy attack. This hardfork was pushed to February 2019, and scheduled to occur on block #7,280,000.

In order to solve the vulnerability issue, the team decided to have two hardforks, Constantinople and St. Petersburg, both of which would occur on the same block. This first upgrade would implement all five proposed protocols and the second upgrade would either disable the EIP paving way for the vulnerability or downgrade the update. This was later declared successful by the members of the Foundation, with the hardfork taking place on February 28, 2019.

Hello Istanbul!

The team is currently getting ready for the next hardfork, which will take place in about eight months from now. According to reports, this hardfork could also include the proposal made for Constantinople hardfork, and the estimated deadline to submit all the proposals for Istanbul is slated to be May 2019.

However, July 2019 would see the soft implementation of Istanbul compatibility on all Ethereum clients and August 2019 is the estimated timeline for the Testnet upgrade. Finally, the hardfork is expected to go live in the month of October, 2019.

Other upgrades in Pipeline:

Apart from Istanbul, other upgrades the team is focusing on are Ethereum 2.0 aka Serenity, the final phase and ProgPow implementation.

ProgPow, aka Programmatic Proof-of-Work is the upgrade that is much-awaited by the mining community of Ethereum. Due to rising concerns over centralization, this implementation will reportedly bring down the control of ASIC miners and support the GPU mining part of the community.

Serenity is the final phase of Ethereum. The main highlight of the upgrade is the shift from Proof-of-Work consensus algorithm to Proof-of-Stake Consensus algorithm and the introduction of Beacon and Casper on Ethereum. This phase would also make way for the eWasm upgrade.

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