Quote from: johnyj on February 10, 2016, 11:25:24 PM

Quote from: madjules007 on February 10, 2016, 10:48:01 PM

The question is absolutely not "can more than 2mb can be uploaded?" The question is not, is it possible to run a node? The question is, at what point do bandwidth limitations disincentivize the operation of full nodes to the extent that centralization endangers security and fungibility? We already know that over the past several years, as block size has gradually increased, operating nodes have persistently fallen. Would you suggest that block size, which is directly related to bandwidth requirements for nodes, is not related to the perpetual decline in nodes? As a node operator, I can tell you that bandwidth is the only possible reason why I wouldn't run a node (as opposed to storage, hard disk resources, hardware). That's the only pressure. Most people do not have unlimited fiber connections. Most people have capped-bandwidth cable or low quality DSL. So the question is not, "can these people run a node, using much or all of their upload bandwidth? Or will they choose not to? The latter is what we must contend with -- and is related to the perpetual decline in nodes over the past couple years.

The falling of full node count is a simple result of people prefer to use off-chain web wallets because of their simplicity and convenience (Before they were using full nodes as their wallet). In fact 99% of my transactions nowadays happen between exchanges and web wallets, my node is never used to process transaction, but simply works as a dedicated mining/relay node

Any proof of this, or just based on your personal anecdote?

Quote from: johnyj on February 10, 2016, 11:25:24 PM

This trend will continue, majority of the average user will often forget about their password or get their phone/computer hacked easily. So they would prefer a human maintained service so that they can reset the password or use 2FA login to increase security (And in case they lose the 2FA device, they also need human support to reset it)

That's sad, as it defeats the purpose of bitcoin, but...SPV and off-chain solutions are fine as long as the number of full nodes remains healthy enough. It's not about growth in SPV or off-chain usage -- it's about decline in full nodes. You can talk all day about how SPV nodes are growing, but if in the end full nodes become highly centralized in the process, bitcoin is susceptible to many security failures.

Quote from: johnyj on February 10, 2016, 11:25:24 PM

On the other hand, thousands of enthusiasts with enough IT expertise will set up dedicated full nodes around the world, they understand bitcoin much better than average Joe, and they will make sure that all these nodes meet the technical requirement of current block size limit

Will they? It's not about whether they understand the technical requirements -- it's whether they are willing to sacrifice the bandwidth at any cost. How do you know?