On June 30, 2022, the Ethereum (ETH) blockchain activated Gray Glacier, your latest system update. One of the key announcements of this update was to delay the detonation of the “Ethereum difficulty bomb”. In fact, Gray Glacier's sole purpose was to delay the bombing by another 100 days.
In this article, we will look at what the “Ethereum complexity bomb” is, why it is needed, and how its delay affects the Ethereum blockchain.
What is the “difficulty bomb” of Ethereum?
Since August 2015, starting from block 200, the Ethereum blockchain program code has been built increasing the difficulty level of mining. Increasing the level of mining difficulty, in turn, leads to an increase in the block time to solve the necessary puzzles, which in turn leads to a decrease in the ETH reward.
As mining difficulty increases, there eventually comes a point where Mining becomes impossible, or rather, completely unprofitable. Here, “mining difficulty” refers to the hashrate, or the amount of hash energy that miners must expend to solve a block of transactions.
This rise in difficulty levels, as well as the point at which difficulty reaches critical mass, has been dubbed the “Ethereum difficulty bomb.” Although it can be called a "bomb", it does not instantly raise the difficulty level to almost impossible heights. Instead, it is designed to increase the level of difficulty exponentially until miners stop mining and producing blocks.
However, the Ethereum development team has significant leverage over the duration of the bomb through updates and patches. Since the concept's inception, several system upgrades have been implemented to delay the "detonation" of the bomb.
Difficulty Bomb Update Timing
Having worked in August 2015, the increase in complexity became noticeable only a year later, in November 2016. Since then, several hard fork updates have delayed the detonation of the bomb, i.e. the point at which ETH mining becomes almost useless. These updates included:
- October 2017: Byzantium Fork
- February 2019: Constantinople upgrade
- January 2020: Muir Glacier update
- August 2021: London hard fork
- June 2022: Gray Glacier upgrade
Muir Glacier and Gray Glacier were introduced specifically to delay the difficulty bomb.
The Gray Glacier update delays the bomb by about 100 days, with the estimated detonation date pushed back to late September or October 2022.
Why the Ethereum Difficulty Bomb?
Putting aside the many years of delays in the detonation of the bomb, one may wonder why this difficulty bomb is needed at all. The answer lies in the long-planned shift of the blockchain from the current proof-of-work (PoW) block validation method to more efficient proof-of-stake (PoS).
The inefficiency of Ethereum 1.0 and the launch of the Beacon Chain
The current Ethereum main chain, Ethereum 1.0, was launched in July 2015 and is based on the same PoS block confirmation system as Bitcoin. Unfortunately PoW is extremely energy intensive, slow and limited. As a result, despite being the world's leading platform for decentralized applications (DApps), the Ethereum network operates at a terrifying speed of only 12-25 transactions per second (GST). While this is still faster than Bitcoin's 7 TPS speed, it is much slower than what the vast majority of PoS chains are capable of.
This rate limit – combined with the huge collection of over 3 DApps running on the network – caused significant network congestion problems and made Ethereum one of the least accessible chains to use. The Ethereum blockchain has perhaps the highest transaction fees of any popular DApp-enabled platform.
Back in 2015, the Ethereum co-founders and development team foresaw the problems that PoW consensus verification would eventually cause. In the future it was planned to create Ethereum 2.0, a version of the network based on PoS.
Ethereum 2.0 was conceived as a sharded platform, where each shard is a separate subchain that runs in parallel with other shards on the network. The network can have up to 64 shards, as well as a “super chain” that will control and coordinate the work of the shards. When the current Ethereum 1.0 chain stops producing blocks, it will become one of the shards.
In December 2020, Ethereum developers launched Beacon Chain, the coordinating superchain for Ethereum 2.0. At the core Beacon Chain lies more efficient and scalable PoS block validation. The launch of Beacon Chain is a key step in Ethereum's transition to a PoS-based network.
Forcing the transition to Ethereum 2.0
Moving from an inefficient PoW network to a much more scalable Ethereum 2.0 appears to be a win-win situation for all stakeholders: core developers, co-founders, user community, DApp operators – and pretty much everyone else.
However, miners running Ethereum 1.0 will never be impressed with this move. These miners, as well as numerous individuals and businesses, have invested huge sums of money in PoW mining machines for Ethereum 1.0. Moving to a PoS platform will make all this equipment and business obsolete.
At the same time, Ethereum needs as many parties as possible to participate in block verification on the new PoS platform. The Ethereum Difficulty Bomb is designed specifically to address this issue, as its secondary purpose is to encourage Ethereum 1.0 miners to turn their resources and efforts towards Ethereum 2.0 mining.
When block mining on the current PoW-based Ethereum blockchain becomes useless due to an explosion in difficulty, miners (at least a significant portion of them) will hopefully join the ranks of Ethereum 2.0 validators.
Why is the explosion of the Ethereum difficulty bomb delayed?
The main reason for the constant delays in the difficulty bomb explosion is that the Ethereum core developers and key stakeholders do not consider the network ready for a full transition to PoS. Since Ethereum is home to so many DApps, any transition to a new network must be carefully prepared.
Prior to the launch of Beacon Chain, Ethereum 2.0 was still mostly a concept under development. In those years, the “difficulty bomb” was mostly a reminder to the mining community to prepare for a future transition. However, ever since the beacon chain went live, there has been a constant sense of anticipation in the community for the actual transition to Ethereum 2.0.
Unfortunately, there were problems during the development process, due to which the explosion of the bomb was constantly delayed, delayed ... and delayed again. After the Gray Glacier update, we are promised a big bang sometime in September or October. If another delay occurs at this point, ridicule and sharp satire from Ethereum competitors can be expected. To date, the Ethereum difficulty bomb has already become the longest delay in the blockchain industry, surpassing Cardano’s four-year wait from 2017 to 2021 for the implementation of smart contracts.