Bitcoin Cash has won a significant amount of market value, infrastructure and community support by providing a compelling vision that resonates with many. The main question now is can the vision succeed without devolving into a dystopia with two or three mega data centers processing all transactions?
The relationship between centralization and blockchain size remains controversial. One of the main variables being studied is block propagation time. The time it takes for a newly found block to reach the rest of the network is critical for a fair playing field for miners. Intuitively, as the size of a block goes up, the longer it may take to reach the rest of the network. This puts pressure on miners to join larger and larger pools so they don’t waste their resources mining without the newest state.
Active research is being done into allowing massively large blocks by decoupling block size from network propagation delay. One promising proposal to deal with propagation delay is to impose canonical ordering on the transactions within a block. Removing the ordering of transactions as a possible variable simplifies the set reconciliation problem. This greatly reduces the amount of information needed to transmit the contents of a block. Assuming network participants have access to the same list of transactions in the memory pool, propagation can approach a constant time.
Constraining the ordering of transactions within a block will allow Bitcoin Cash to eventually adopt the Graphene algorithm for network propagation. This research, led by Gavin Andresen of UMass Amherst, greatly diminishes objections to larger blocks based on mining centralization forces.