Ethereum’s Constantinople upgrade: A technical overview

Constantinople is a complicated upgrade that combines five major Ethereum Improvement Proposals, or EIPs for short, proposed by prominent Ethereum developers such as Vitalik Buterin, Wei Fang, and also Vlad Zamfir, who just recently left the Ethereum foundation to work on his own Casper protocol.

The Constantinople update is the last piece of the Metropolis upgrade and will bring much needed network improvements, making way for proof-of-stake (PoS) and sharding which will come with the upcoming Serenity upgrade.

Ethereum roadmap

Before we dive deep into the belly of the beast, it’s important to remember Ethereum’s previous and actual roadmap. Since its initial release, it has suffered multiple crucial upgrades (both hard forks and soft forks, as explained in this guide).

Each single upgrade below represents an important milestone for the Ethereum network, as it moves from a proof-of-work (PoW) consensus protocol into proof-of-stake with the ultimate goal of being a world computer, home to all the best dApps.

At the time of writing, the most up-to-date Ethereum roadmap looks like this:

Constantinople enhancements overview

There are five major goals Constantinople aims to achieve, as reported by Coin Rivet, and each EIP promotes a different change to the protocol:

• EIP 145: Bitwise Shifting Instructions [efficiency and speed]: This improvement means the execution of shifts in smart contracts will be ten times cheaper.
• EIP 1052: Smart Contract Verification [speed and energy]: This change allows for smart contracts to verify one another by pulling just the hash of the other smart contract.
• EIP 1014: CREATE2 [scalability]: This upgrade improves the enablement of state channels, an Ethereum scaling solution based on off-chain transactions.
• EIP 1283: SSTORE [cost]: This change will reduce the gas cost for the SSTORE operation. This reduction enables multiple updates to occur within a transaction more cheaply.
• EIP 1234 Block Rewards & Difficulty Bomb Delay [the big one]: This is the big change for the network. It is comprised of two components: block reward reduction (from three to two ETH) and difficulty bomb delay.

Each EIP is a layer of improvements on top of previous enhancements done during the Homestead and Byzantium upgrades.

The above improvements will help sidechains interact with the Ethereum blockchain (EIP 1014) by making it easier to bridge data in-between networks (EIP 1283), as well as allowing for cheaper smart contract functionality (EIP 145 and 1052) to be implemented. The delay of the difficulty bomb, which will in essence make PoW obsolete in Ethereum, was contested by some members of the community, although due to the delay in the release of Casper’s PoS, I understand why the foundation opted to not impose a difficulty increase.

Client acceptance

At the time of writing, all major clients communicating with the Ethereum blockchain, such as Parity, Geth, and so on, have all accepted and upgraded their infrastructure to match the upcoming Constantinople hard fork, as we can see below.

I’m not expecting any issues with the upgrade tomorrow. By moving forward with Constantinople, the Ethereum Foundation proved their resilience against adversity (once more), an important feature for any project that wishes to survive the long bear market we’re currently facing.

The long-term vision Vitalik imprinted on the Ethereum Foundation team is what excites me the most. As he said during the DevCon4 conference in October 2018:

“Ethereum 2.0 is a combination of a bunch of different features that we’ve been talking about for several years, researching for several years, actively building for several years that are finally about to come together in one cohesive whole.”

At the end of the day, technology simply creates newer frameworks for humans to communicate and exchange value differently. By developing its network towards a cheaper, more scalable, and decentralised ecosystem, Ethereum is making sure it maintains its value-capture model by remaining a central piece in the cryptocurrency sphere.

Nicely done!