# Ethereum Research Update

DevFeed: [Ethereum Research Update](<https://devfeed.tech/articles/ethereum-research-update-16792.md>)

Original publisher: [Read original article](<https://blog.ethereum.org/en/2016/12/04/ethereum-research-update>)

Author: Vitalik Buterin

Published: 2016-12-04T11:27:47Z

Content type: article

Language: en

Sources: [Ethereum Foundation Blog](<https://devfeed.tech/sources/ethereum-foundation-blog.md>)

Topics: [Ethereum](<https://devfeed.tech/topics/ethereum.md>), [Network](<https://devfeed.tech/topics/network.md>), [DDoS](<https://devfeed.tech/topics/ddos.md>), [Metropolis](<https://devfeed.tech/topics/metropolis.md>), [Protocol (disambiguation)](<https://devfeed.tech/topics/protocol.md>), [Solidity](<https://devfeed.tech/topics/solidity.md>), [C++](<https://devfeed.tech/topics/c-plus-plus.md>), [Go](<https://devfeed.tech/topics/go.md>), [Cryptography](<https://devfeed.tech/topics/cryptography.md>)

Tags: [attacks](<https://devfeed.tech/tags/attacks.md>), [c-plus-plus](<https://devfeed.tech/tags/c-plus-plus.md>), [development](<https://devfeed.tech/tags/development.md>), [ethereum](<https://devfeed.tech/tags/ethereum.md>), [fork](<https://devfeed.tech/tags/fork.md>), [go](<https://devfeed.tech/tags/go.md>), [metropolis](<https://devfeed.tech/tags/metropolis.md>), [network](<https://devfeed.tech/tags/network.md>), [protocol](<https://devfeed.tech/tags/protocol.md>), [research](<https://devfeed.tech/tags/research.md>), [research-development](<https://devfeed.tech/tags/research-development.md>), [security](<https://devfeed.tech/tags/security.md>)

## AI overview

Ethereum's fourth hard fork, Spurious Dragon, and the related state-clearing process completed the planned response to recent denial-of-service attacks. The update also describes client-development progress and planned protocol improvements for the Metropolis hard fork.

## Source excerpt

This week marks the completion of our fourth hard fork, Spurious Dragon, and the subsequent state clearing process, the final steps in the two-hard-fork solution to the recent Ethereum denial of service attacks that slowed down the network in September and October. Gas limits are in the proce...