Bitcoin is a decentralised currency, meaning no single entity controls it and everyone can be a Bitcoin user. Bitcoin uses peer-to-peer technology to operate with no central authority: managing transactions and issuing money are carried out collectively by the Bitcoin network. Bitcoin is open-source; its design is public, nobody owns or controls Bitcoin and everyone can take part. Through many of its unique properties, Bitcoin allows exciting uses that could not be covered by any previous payment system. Visit https://bitcoinera.app/ for further information.
Bitcoin Classic is a software through which users can increase their Bitcoin block size from 1 to 2 MB in order to make Bitcoin more scalable. It was created when there was disagreement about how Bitcoin’s block size should scale. It represents one on how that should work, but Bitcoin still faces a scaling challenge, and Bitcoin Classic is not the only solution. Bitcoin Classic allows Bitcoin miners to signal their choice of Bitcoin block size, with each variant represented by a separate numeric value. While it’s possible that Bitcoin will follow Bitcoin Classic’s approach, other solutions may emerge or grow as well.
The Bitcoin block size is a hotly debated topic. There are four solutions being proposed as the next step for Bitcoin by leading community members. Let’s review each of them!
The Bitcoin Classic team, headed up by Jonathan Toomim, has been putting together a fork of Bitcoin Core that implements a 2MB block size increase. They’ve recently released it as version 1.2 beta and have begun using their solution to mine new blocks on the test net. The plan is for this fork to be activated in March 2016, after which all miners will need to begin mining with Bitcoin Classic in order to produce valid blocks.
Bitcoin Classic also contains several other changes that have been previously discussed as potential improvements to Bitcoin. You can read about those changes in Bitcoin Classic’s release notes.
At least three members of Bitcoin Core have stated that they do not support Bitcoin Classic. Gregory Maxwell has said “It is very likely that the Bitcoin economy will converge to an agreement about changes to take place in a distant future after it becomes clear how Bitcoin performs with larger blocks”, and Wladimir J. van der Laan says “I agree with what Gavin said so if you want my support you need at least a rough consensus from the people I trust.” Pieter Wuille has also been quoted saying “We still fail to see how this would be better than just increasing [the] block size limit. We’re not going to merge this code as long as we disagree, which means it’ll probably never be merged.”
Additionally, Bitcoin Core developer Luke Dashjr stated that Bitcoin Classic “does not solve the actual problem” of Bitcoin’s capacity and made a pull request to Bitcoin Core proposing changes that would implement more extensive testing of the network. It’s expected that this will become Bitcoin Core v0.12.0.
The Bitcoin Unlimited project is an alternative solution for scaling Bitcoin proposed by Coingeek and headed up by Andrew Clifford. It takes a very different approach to the block size limit than Bitcoin Classic: instead of fixed limits, it proposes allowing miners and users to vote on block size through miner votes weighted by hash rate and user votes weighted by bitcoin value (using BIP-100 ). The difficulty adjustment algorithm will also be altered to allow Bitcoin Unlimited nodes to switch to lower difficulties in order to mine larger blocks and catch up with Bitcoin Core. Bitcoin Unlimited also considers removing the block size limit in its current form and replacing it with a new hard limit that might be increased in the future after thorough testing. Finally, Bitcoin Unlimited plans on implementing more extensive testing of its changes through Bitcoin Classic-like beta releases before finalising them.
The Bitcoin XT team, headed up by Gavin Andresen, is another alternative solution for scaling Bitcoin. It takes a slightly different approach than Bitcoin Classic or Bitcoin Unlimited: instead of allowing miners and users to vote on block size limits through miner votes and user votes (e.g., BIP-100), it proposes changing Bitcoin’s block size limit to 8MB through Bitcoin Improvement Proposal 101. Bitcoin XT also implements BIP-101, which allows miners to vote on the maximum acceptable value for the Bitcoin block size. If Bitcoin XT becomes widely used, it will likely become difficult or impossible to increase Bitcoin’s block size in the future; however, Bitcoin XT only offers an 8MB limit.