“Poison Blocks” aka Big Block Attacks Prove that Bitcoin Needs 128MB Blocksize
A controversial post appeared on /r/btc earlier today explaining why we need 128MB blocksize on the bitcoin network. In the post, /u/ratifythis explained why “poison blocks” and basic economics justify raising the blocksize to 128MB.
Essentially, the user argued that big block attacks will push the bitcoin network forward. Big block attacks occur when a larger miner terrorizes smaller miners with oversized blocks. Instead of seeing this as a problem – like small blocksize supporters – Ratifythis sees this as the natural next phase of competition that will push bitcoin forward.
For those out of the loop, the entire bitcoin community – including BTC and BCH – has been debating how to scale for years. In 2017, disagreements over how to scale led to the split. Bitcoin, on August 1, 2017, split into BTC and BCH. BCH scaled the network by raising blocksize limit to 8MB, and then later to 32MB. BTC’s blocksize limit remains at 1MB as developers attempt to release Lightning Network, an off-chain scaling solution.
Now, within the BCH community, we have another split. BCH’s blocksize already sits at 32MB. That means higher transactional capacity on the BCH network. Instead of accommodating just, say, 1,000 transactions in each block every 10 minutes, BCH can accommodate 32 times that number.
Certain members of the bitcoin community – including Craig Wright and the team at nChain – believe we can do better than a 32MB blocksize. Craig Wright, the Australian computer scientist who has previously claimed to be Satoshi Nakamoto, wants to scale BCH all the way up to 128MB.
A 128MB blocksize is a controversial addition to the BCH network. Some miners support it, while others oppose it. Some claim it will lead to increased centralization of mining power as only the biggest miners will be able to accommodate the larger blocks. Others claim it’s giving BCH the transactional capacity it needs to be the world’s best payment protocol.
Amidst all of this controversy, /u/ratifythis posted to Reddit’s BCH-friendly, Roger Ver-controlled /r/btc forum earlier today.
“So-called “Poison Blocks” (what Greg Maxwell called the “big block attack”) are the way Bitcoin was designed to scale and the ONLY way it ever can,” the user began.
Ratifythis goes on to explain that, due to basic economics, bitcoin will function better with 128MB blocks.
You can read the entire post here. The post garnered only moderate attention on the /r/btc subreddit. Earlier today, however, Craig Wright tweeted that the post was, “A good read” and linked to the post on Twitter.
Is A 128MB Blocksize The Best Way Forward For Bitcoin?
/u/Ratifythis brings up a number of points to suggest that 128MB blocksize is the best way forward for bitcoin. Essentially, the user is arguing that 128MB blocksize doesn’t limit competition on the bitcoin network – it’s just the natural next step for bitcoin’s competitive ecosystem. Since 2009, bitcoin’s network has been secured by competition. Ratifythis sees Bitcoin Core’s scaling approach as a “socialist mindset” that hurts the original intention of bitcoin.
Here are some of the points that Ratifythis brings up to support 128MB blocksize:
- Bitcoin miners “compete ruthlessly” on hashrate. Because of this competition, 51% attacks are discouraged. “Security is fully within the purview of cutthroat market competition, and the result is that it works and works excellently,” explains /u/Ratifythis.
- “Miners don’t yet compete on networking to any great degree.” The user cites a video by Joannes Vermorel who argues that even with terabyte blocks, there would be no great budgetary strain even for small miners. “The artificial blocksize cap is preventing networking from falling fully under the purview of cutthroat market competition, and therefore it doesn’t fully work.”
- Some of the worst miners on the network are effectively being subsidized because volunteer dev teams supply node client code. This keeps the node code from falling fully under the purview of cutthroat market competition. Instead of competing with better code, miners compete on hashrate. “and as a result – surprise, surprise – the node code is insufficient and “lots of work is needed to get to 128MB.”
- Some people claim this is a reason to not lift the cap. Lifting the cap would force miners to do work and compete in new areas.
- Ratifythis compares this to “the kind of socialist mindset that thinks cutthroat competion [sic] among seatbelt makers would lead to seatbelts that kill you.”
- By shielding miners from their inability or unwillingness to suitably optimize their node software is leading to a problem in the bitcoin network: we’re filling bitcoin with unprofessional miners who cannot take us to global adoption.
- 1MB blocksize supporters frequently bring up the idea that larger blocksize will limit the number of devices on which a full node can run. We won’t be able to run a full node on a Raspberry Pi or a low-end laptop, for example. “The fact that people are still arguing against 128MB by referencing tests with laptop nodes suggests that's the real problem here. Core's full node religion still has sway, despite being manufactured from whole cloth. Also known as Blockstream Syndrome, as a play off Stockholm Syndrome (where captives begin to sympathize with their captors).”
Bitcoin “Must Scale” Using Poison Blocks And Big Block Attacks
Here’s where /u/ratifythis makes things interesting. Opponents of blocksize limits frequently claim that “poison blocks” and “big block attacks” will be used by larger miners to force out smaller miners. Under these types of attacks, a big miner can terrorize a smaller miner using oversized blocks that a sizable minority of the network can’t handle due to their slow networking.
Some see poison blocks and big block attacks as a problem. They see it as a reason to keep blocksize low. Ratifythis, however, sees things differently:
“Greg Maxwell's “big block attack” where big miners try to terrorize smaller (less well capitalized) miners using oversized blocks that a sizable minority of the network can't handle due to their slow networking is in fact exactly how Bitcoin MUST scale.
It's not an attack, it's a stress test, and one Bitcoin literally cannot scale without. What he called an attack is the solution to scaling, not any kind of problem. Stress tests are incentivized in Bitcoin as a way of calling the bluff of the lazy miners. You gamble some money on an “attack,” see who the slowpokes are and take their block rewards for your own.”
So far, no miner has taken the risk to pull off a big block attack. But they could be coming.
Ultimately, Ratifythis is arguing that bitcoin succeeds when we have pure competition across all aspects of the bitcoin network. Higher blocksize limits wouldn’t stifle competition: they would encourage competition in new areas. This competition is what has taken bitcoin to the place it is today.
The entire post is worth a read here. Although it hasn’t gained much traction on /r/btc (27 upvotes and 73% upvoted at the time of writing), the post has clearly been approved by Craig Wright.