[BIP Draft] P2P UTXO Set Sharing

The process of getting started with validating blocks and transactions at the current tip, particularly in terms of receiving payments, involves substantial data handling requirements. Specifically, obtaining the full Bitcoin blockchain necessitates downloading approximately 600GB of data. With an optimal bandwidth scenario, such as a 250Mbps connection featuring perfectly well-behaved peers, this download can take just under seven hours. This timeframe is feasible for modern PCs, which are capable of validating the blockchain within a similar duration.

However, bandwidth often presents a bottleneck at the consumer level, potentially prolonging this process. An alternative solution to alleviate this burden is the AssumeUTXO approach, which significantly reduces the initial download requirement. By using a utxo snapshot at block 935000, the required data shrinks to under 9GB. In an ideal network environment with a speed of 100Mbps, this snapshot can be downloaded in approximately 15 minutes. Adding between 8GB and 34GB of actual block data, depending on the age of the utxo snapshot used (ranging from 4 to 17 weeks), the total time needed might extend to about 30 minutes to one hour. This reduced time scale makes it possible to complete the task over a typical lunch break rather than requiring an overnight duration.

These insights are crucial considering common misconceptions about the time needed for a fresh Initial Block Download (IBD), especially from remote locations like Australia, where users previously anticipated multiple days or even a week for completion. Sharing this updated information helps adjust expectations and planning for those involved in Bitcoin development and transactions.