
Ethereum HODLers, rejoice. The world’s 2nd biggest cryptocurrency has successfully concluded its latest hardfork, Istanbul, allowing Ethereum to take another step towards Serenity, its 2.0 Proof-of-Stake (PoS) final form.
The network upgrade was officially implemented system-wide at block number 9,069,000, just after midnight UTC today (Sunday 8 December 2019).
It marks the third successful hardfork for the popular virtual asset blockchain in 2019, and follows simultaneous and oft-delayed St. Petersburg and Constantinople hardforks in February this year ( here’s our recap). Istanbul is the 8th overall upgrade since the Ethereum project started in 2015.
Last-minute drama (again)
Just as with the February updates, there was once again a bit of last-minute running around. As readers may recall, Constantinople was delayed In January mere hours before deployment, after a third party discovered a potentially devastating bug hidden within one of the EIPs.
Ethereum client Parity, which makes up about ¼ of the network, posted a last-minute cry for help on Twitter for EIP 1344, urging users to upgrade after they forgot to do so themselves. Luckily devs were able to create and implement the necessary changes in time.
https://twitter.com/ParityTech/status/1202636162734731264
What’s new in Ethereum’s Istanbul?

The latest Ethereum update includes 6 Ethereum Improvement Protocols (EIPs), which were agreed to and installed by all Ethereum clients for a system-wide update. They are:
- EIP 152: Creates bridge between ETH and Equihash-type PoW assets like ZCash
- EIP 1344: Boosts protection against Denial-of-service (DDoS) attack
- EIP 1108: Proposes zk-SNARKS proofs to scale network and drop gas costs
- EIP 1844: introduces Ethereum Virtual Machine (EVM) opcodes to balance gas costs vs resource usage
- EIP 2028 and 2200: reduces excess gas costs associated with transactional data
How does Istanbul Improve Ethereum?
Here are 6 ways that the Istanbul hardfork will improve the Ethereum network:
- Faster: in terms of transactional speed (TPS)
- Cheaper: lower gas costs (gwei)
- More scalable: for off-chain data solutions
- More secure: better resilience against DDOS attacks (that previously plagued the network)
- More stable: More bandwidth means more network stability
- More interoperable: enables a bridge between Ethereum and zero-knowledge privacy technology, such as ZCash
How does Istanbul affect Ethereum users?
According to Consensys, the Istanbul hardfork shouldn’t affect users who keep their ETH on reputable hardware wallets, exchanges and software-based wallets. Please check with your wallet provider though.
CoolWallet S and Ethereum Istanbul

CoolWallet S users should be unaffected by Ethereum’s Istanbul hardfork. If you experience any issues though, please get in touch with our Support team on our website.
Serenity, not yet
Ethereum’s Istanbul hardfork is one of the final updates in Ethereum’s current Proof-of-Work (PoW) model, which has been heavily criticized for its electricity-guzzling mining that’s required to keep the network going.

Istanbul helps clears the path to Ethereum 2.0, also known as Serenity, which is set to be the last stage in the network’s development and should be implemented by 2021. With Serenity, Ethereum will move to a more energy-efficient, scalable and stable blockchain.
Ethereum 2.0 Serenity Road Map: 2020 – 2022
Here’s what remains for Ethereum in the leadup to the switch to Serenity:

- Phase 0: Beacon Chain (Q1/2020)
- Phase 1: Shard Chains (2021)
- Phase 2: eWASM (New Ethereum Virtual Machine) (2021)
- Phase 3: Continued Improvement (2022)