The Problem

I've always assumed Bitcoin would, in time, become the worlds one and only currency. However, after the recent scaling debate, I've decided this may not be the case due to the exponential nature of the blockchain's size. That is, as more people use Bitcoin for more things there are more transactions/day meaning the size of the blockchain grows faster. In my opinion, the problem with scaling Bitcoin isn't transactions/second (there are lots of solutions to this problem) it's the size of the blockchain.

Right now the blockchain is about 127 GBs large. If Segwit2x becomes fully implemented and Bitcoin becomes popular enough to fill each 2 MB block to the brim, the blockchain will grow at 288 MBs/day. That is 105.12 GBs/year. At that rate Bitcoin's blockchain will require approx. 105 TBs of space in 3017. This assumes the blockchain doesn't ever upgrade to allow larger blocks than Segwit2x's 2 MB  per block. This will not be the case. In all likelihood, the BTC protocol will double its block size every 10 - 20 years. This will result in a 1.848 Yottabyte blockchain in 3017. That's 1,848,000,000,000,000 GBs! 

Now, many people will claim that the blockchain's size's rate of growth will never exceed that of storage density. Meaning that while 1.848 YBs may seem stupidly large by today's standards it will be nothing in 3017. That just isn't true.

Many people believed in Moore's law. I say believed because most people who follow microchip technology (of which I am not one) would agree that semiconductor technology has started to rub up against the walls of  quantum physics. That is, the semiconductors that make up modern microchips are close to their smallest possible size.

I bring this up because data storage, like microchips has quantum limits that will eventually prevent it from becoming more efficient. This means an average computer is the year 3017 will likely not have a drive capable of holding even close to 1.848 YBs. This means Bitcoin's current path isn't sustainable. Sure, it will work for a hundred or even a 1000 years if my calculations are a little aggressive, but in the end the blockchain will just grow to large.

So, why should I care? I won't be alive then. Bitcoin won't start to feel the effects of this problem for centuries. You're right, but that shouldn't matter. Most true believers of Bitcoin (and blockchain tech as a whole) think in lifetimes. Not years.

The Solution

So, how do we solve this. Personally, I see a few angles of attack.

The first, and most obvious way to attack this problem is side chains (Segwit). While this doesn't solve the problem it slows it down significantly because, when used to their full extent, I think side chains can reduce Bitcoin's transaction load by 90+%.

The second, and more important, attack point is Bitcoin's protocol. Currently Bitcoin archival nodes keep the entire history of the Bitcoin blockchain because that is the only way to prove mathematically prove chain of ownership and to prevent double spend attacks, but this is only because people require Bitcoin to be trustless. That is, the Bitcoin protocol requires users to be able to trace their coins back to their genesis because it believes no users should be required to trust anyone else to use Bitcoin. This doesn't need to be the case.

I envision a topping protocol that would allow Bitcoin nodes to, after coming to a consensus, delete transactions that are X number of blocks old. This would turn those transaction's recipients into coin genesis points. This solution isn't perfect and likely won't need to be implemented for decades if not centuries, but I think it strikes a balance between trustlessness (an important quality of the blockchain) and long term scalability.

Resteem and Upvote to let others see this please!