I think Bitcoin can increase the blocksize now, therefore it is not a problem for the alternative cryptocurrencies to do so, however even if you believe that this is impossible, or it leads to dangerous centralization, which I disagree with obviously, alternative solutions do exists, like incentivized full nodes and self funding blockchains.
You're forgetting the alternative solution estimated to allow billions of people to make essentially unlimited transactions while retaining node decentralisation once technology makes it safe to scale up to 150MB blocks--
lightning network.
I have not forgotten this at all, I do not consider the lighting network to be a solution for scaling the Bitcoin blockchain directly at all both because it adds a layer of abstraction that is not good for the user experience, and because there are no decentralized solutions to routing yet. The same is true for side chains, so far only federated side chains have proven to be viable, these solutions are essentially centralized third parties, in the case of lighting network they are at least trustless third parties. However I would consider being able to transact on the Bitcoin blockchain directly, and transfer value directly without the need for any third parties, a superior design. Considering that this is possible, Bitcoin can scale. It makes sense to me that this is the path we should take.
By restricting the growth of Bitcoin with such an arbitrary limit we would be turning Bitcoin into a type of settlement network, fundamentally changing the economic policy of Bitcoin. I do question what the point of such settlement layer even would be in a world where everyone can transact directly, cheaply, easily and quickly. It is almost as if the very idea of a settlement layer might even be antithetical to a world where cryptocurrency becomes the dominant form of currency, rendered obsolete like many of the other functions that banks carry out today.
A settlement layer is what large financial institutions use to settle balances between them. It is exclusive, elitist and reinforces or recreates the power structures we have today. By attempting to turn Bitcoin into a settlement layer we are turning it into the very financial systems Bitcoin was meant to counter. I find the entire idea to be unrealistic however, the large banks and financial institutions would be much better off if they designed their own systems for this purpose, even Ripple is a better settlement network then Bitcoin, I do not think these large financial institutions would even adopt Bitcoin because it is not in their interests to do so, the only way I see that happening is because they are "forced" to do so in order to stay relevant, and that could only happen because of mass adoption of Bitcoin as a currency. Not increasing the blocksize undermines Bitcoins ability to be a currency as was always intended, the whitepaper even describes this in its title, Bitcoin: A peer-to-peer Electronic Cash System.
https://medium.com/@jgarzik/bitcoin-is-being-hot-wired-for-settlement-a5beb1df223a#.ozf3pv3vsObviously 150MB blocks are a long ways off from where we are now, but they're certainly closer than the 24GB blocks which would be needed under the current design to allow a similar throughput.
We do not need to increase the blocksize to twenty four gigabyte blocks or whatever, we only need to increase it enough to keep up with demand so that we preserve the economic properties of Bitcoin.
If adoption does increase faster then technological progress then Bitcoin will hit a limit and that is fine, fees will go up and people will move elsewhere as use cases are pushed out, off chain solutions will also help relieve pressure on the main chain. However restricting the growth of Bitcoin now when it is not even necessary is wrong and will most likely lead to its obsolescence. Especially considering that alternative cryptocurrencies are able to scale their blockchains directly, Bitcoin does need to be able to compete.
http://konradsgraf.com/blog1/tag/block-size-debateThe Core plan for blocksize increase is not, "never", but, "not today".
This is not good enough for a six billion dollar economy, they can not even commit to a blocksize increase beyond 2017. Which businesses rely on, certain use cases are pushed out, uncertainty is not good for the market. Not to mention that because of the complexity of segwit the possibility of further blocksize increases might even not be possible because parts of the new code might break when it is increased again according to Core.
It seems that they have judged the difficulties associated with deploying a hard-fork to 2MB outweigh the gains which might be had from such a small increase.
Doubling the capacity of the network is not a small increase and would do much good for the entire Bitcoin ecosystem, by refusing to even do this they have made there position quite clear that they are completely unwilling to compromise on this issue, this has the effect of further widening the rift in the community.
Segwit is far more complex and difficult to implement compared to increasing the blocksize limit, to increase the blocksize limit itself is literally only one line of code, Segwit has thousands of lines of code, and is full of unnecessary complexity in part due to the soft fork. The soft fork method of "anyonecanspend" is an ugly hack essentially neutering all of the nodes that do not upgrade, it might as well be a hard fork, considering that even the blocksize limit itself can be increased using this soft fork method, it certainly does disprove this notion that soft forks are good and hard forks are bad, it depends more on the content of the changes that are made.
Maybe after we see segwit and weak blocks/IBLTs implemented to alleviate some of the technical limitations we can consider a blocksize increase, perhaps to something more substantial than 2MB, though as the calculations regarding the bandwidth/computational resources required for any given blocksize are beyond me, I won't make any guesses as to what size we might want to target.
We could easily have much larger blocks now compared to what we have today, and these innovations to alleviate some of the technical limitations have already been implemented by alternative implementation like Xthin by Bitcoin Unlimited and head first mining by Bitcoin Classic. The truth is that Bitcoin Core has been more focused recently on building everything they need for off chain scaling, compared to actually scaling the Bitcoin blockchain directly which the alternative implementations are more focused on now.
Or maybe a fork to 2MB will be announced after segwit to attempt to lessen complaints, though I can't imagine this will change the minds of anyone convinced that, "blockstream is evil". My understanding is that segwit will fix the biggest technical problem associated with 2MB blocks (validation times potentially getting really long for particular blocks), but deployment is still a problem regardless.
That is not the case actually validation times have already been addressed in libsecp256k1, so that is no longer an issue. Segwit fixes malleability this is true though it includes many other changes, including an arbitary discount for certain transaction types that benefit the lighting network. The ability to make radical changes to Bitcoin through its scripting language by bypassing the consensus mechanism. It actually makes transactions less efficient, the total capacity is increased but not as much as just increasing the blocksize limit to two megabytes would. There are also some very concerning vulnerabilities that allows malicious miners to steal peoples coins, this vulnerability has so far yet to be addressed, I personally would consider that unacceptable.
Segwit would be better implemented as a hard fork, it would lead to much cleaner and more efficient code. Hard forks are an important part of the governance mechanism of Bitcoin, it should not be avoided but embraced as a test of consensus. Segwit is contentious to say the least, I am not against Segwit itself actually I just think the code should not be rushed and it should be implemented as a hard fork without all of these other changes. Increasing the blocksize to two megabytes now is much safer and is actually the conservative choice, not increasing the blocksize represents a fundamental change to the economic policy of Bitcoin.
https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2015-December/011973.html
