A significant milestone in the world of Bitcoin mining has emerged as seven of the largest mining pools have collectively opted to endorse the Stratum V2 open standard. This move, announced recently, marks one of the most substantial decentralization efforts in the industry in recent years. The pools involved include Foundry, AntPool, F2Pool, SpiderPool, MARA Pool, Block Inc, and DMND, all of which have joined the Stratum V2 working group.
Stratum V2 is an open-source protocol that revolutionizes how mining pools interact with individual miners. One of the most important changes introduced by this new standard is that individual miners are now empowered to construct their own block templates. This shift means that the decision on which transactions get included in each new block now lies with the miners themselves, rather than with the operators of the pools.
According to data from Hashrate Index, Foundry alone commands an impressive 34.2% of the global Bitcoin hashrate, with AntPool contributing 14.2%, F2Pool at 11.3%, and SpiderPool at 10.5%. MARA Pool adds another 4.7%. Collectively, these seven pools represent approximately 75% of the total Bitcoin hashrate, which raises significant implications for the decentralization of transaction selection within the Bitcoin network.
Historically, under the Stratum V1 standard, pool operators have held the majority of decision-making power regarding transaction selection for new blocks. This concentration of power has raised concerns within the community about the potential risks associated with having a small number of pools wielding significant influence over transaction orders. The dominance of a single pool controlling over 30% of the hash rate exacerbates these concerns, as it allows that pool to dictate the order in which transactions are processed in a potentially centralizing manner.
While the adoption of Stratum V2 does not inherently change the concentration of hashrate across these pools, it fundamentally alters who gets to decide what transactions are included in each block. This is a critical concern for the Bitcoin community, which has long worried about the implications of centralized decision-making in the mining process.
The Stratum V2 protocol has existed since 2022 and was conceptualized through a partnership between Braiins and Spiral, which co-founded the working group. Until recently, the protocol was viewed as an experimental project with limited traction. However, with the addition of prominent players like Foundry and AntPool, it now sees increased legitimacy and momentum, signifying the onset of a new phase in its implementation.
The development occurs at a time when the broader mining landscape faces challenges, with CoinShares estimating that up to 20% of miners are currently operating at a loss. The hashprice—the revenue miners earn per unit of computing power—has been hovering around $38.57 per petahash per second daily, which is close to breakeven for those utilizing mid-generation hardware. Additionally, the network difficulty is slated to increase again on May 15, from 132.47 trillion to 135.64 trillion, highlighting the competitive pressures within the mining sector. Currently, the network hashrate stands at an impressive 998 exahash per second, reflecting the ongoing evolution of Bitcoin mining dynamics.
