Bitcoin With Heterogeneous Block Sizes (A Scaling Proposal)


New Member
May 20, 2018
These last months I've been working on a Bitcoin generalization to tackle the problem of scalability without eroding decentralization. The paper is below. I'm looking for others interested in the idea, who want to work on the implementation, and on further research.

Here's a short overview:

The block size problem is well known. If blocks are small there is not enough room for transactions, and fees rise. As blocks get increasingly larger fewer nodes are capable of processing them and hashing power gets more concentrated, increasing the success probability of an attack. The block size set a trade-off between decentralization and transactions throughput.

Heterogeneous blocks is a proposal to solve this with a generalization of Bitcoin. Instead of imposing a single size, a block is redefined as a series of sub-blocks of increasing sizes, each doubling the total size up to that point: 1, 1, 2, 4, 8, 16, 32... The sub-blocks in the series exist as different compromises between decentralization and throughput.

Each miner decides a cutoff in the series, and processes sub-blocks up to that point. For example, a miner that choses a to process 4 sub-blocks, will generate blocks containing the first 4 sub-blocks (with sizes 1, 1, 2, 4), and will process the first 4 sub-blocks at most from blocks generated by others. On the other hand, users choose the sub-block size to use individually for each address and transaction.

The construction has these properties:
- The network reaches consensus despite that not all miners observe the blocks completely.
- Big blocks don't affect the security of small blocks, and bigger sub-blocks don't affect the security of smaller sub-blocks.
- It is possible to move coins between the different sub-blocks.

Heterogeneous blocks can be seen as a having Bitcoin and Bitcoin Cash in a same chain, each serving different use cases. The smallest sub-blocks are the most secure to store savings. The biggest sub-blocks are better for small everyday payments, at the risk of more centralization. And in between there is a whole range of trade-offs between the two.

Bitcoin With Heterogeneous Block Sizes: A Scaling Proposal

Abstract: We propose a bitcoin generalization as a solution to the problem of scalability. The block is redefined as a sequence of sub-blocks of increasing sizes that coexist as different levels of compromise between decentralization and transactions throughput. Miners and users can decide individually the sizes they use without affecting others in the network.

sha256: 057706103ea953b08e67bcc6230d479445480346c2453da58183213aa99bda45

Santi J.


New Member
Dec 18, 2018
Seems like a massive rework that affects every part of the protocol. From wallets to nodes to consensus to mining to block formatting. That's not gonna happen.

One problem I see besides having to redesign everything is the Bitcoin won't be fungible. Ones stuck in high-size blocks are worth less than those in low-size blocks. That's a property we generally agree shouldn't be messed with.