Quote from: gmaxwell on February 05, 2015, 07:53:29 PM

Quote from: ABitNut on February 05, 2015, 09:20:05 AM

Of course, 28 minutes is still long. That is based on 2013 data.

This data is massively outdated... it's before signature caching and ultra-prune, each were easily an order of magnitude (or two) improvements in the transaction dependent parts of propagation delay. It's also prior to block relay network, not to mention the further optimizations proposed but not written yet.

I don't actually think hosts are faster, actually I'd take a bet that they were slower on average, since performance improvements have made it possible to run nodes on smaller hosts than were viable before (e.g. crazy people with Bitcoind on rpi). But we've had software improvements which massively eclipsed anything you would have gotten from hardware improvements. Repeating that level of software improvement is likely impossible, though there is still some room to improve.

There are risks around massively increasing orphan rates in the short term with larger blocks (though far far lower than what those numbers suggest), indeed... thats one of the unaddressed things in current larger block advocacy, though block relay network (and the possibility of efficient set reconciliation) more or less shows that the issues there are not very fundamental though maybe practically important.

In the end, the whole block of transactions must be present on the blockchain at the most distant end of the network in 3 minutes to allow newly discovered blocks to be added upon it. Ideally, you need to transmit 20MB data in 1-2 minutes. Maybe it is possible to use multi-threaded P2P downloading to accelerate the data transfer