In this article, let's go over the most important information regarding the Bitcoin Segwit2x Hard Fork happening in mid-November. This is a topic I have been dodging for a while, due to the deep controversy and polarization it has caused in the Bitcoin community.
However, I feel that it's extremely crucial for everyone holding Bitcoin to know what this hard fork is, when it will occur, what it does, and how to secure your coins. Let's get started!
The mid-November Bitcoin Hard Fork goes by many names, including "Segwit2x", "NYA Agreement", and B2X. These all refer to an attempted hard fork occurring at BTC Block 494,784, with the main goal of the hard fork being a block size increase from 1 MB to 2 MB (hence the '2x').
Hard Forks occur when some miners feel that a change in consensus rules needs to occur (the protocol governing the Bitcoin blockchain needs to change).
These miners will start mining blocks that break the original blockchain, following their own different rules. Miners from one chain will ignore blocks from the other.
If miners continue adding onto both chains (new and old), a chain split has occurred and two new cryptocurrencies have formed. This has already happened before on August 1st, 2017 when some miners began to mine incredibly large blocks. This caused the fork leading to the Bitcoin Cash (BCH) cryptocurrency.
So far, three Bitcoin hard forks have been planned or completed, leading to four possible chains.
The first chain is the "original" Bitcoin chain (the sole chain operating in July 2017).
In August 2017, the first hard fork occurred leading to the birth of Bitcoin Cash (BCH). Bitcoin Cash altered the Bitcoin block size to 8 MB allowing for more transactions to be included in one block, though BCH did not and does not plan to use Segregated Witness (Segwit) on their chain.
Bitcoin Gold altered a lot of how Bitcoin works, changing the proof-of-work algorithm from SHA-256 to EquiHash meaning that it can be mined with computer GPUs. Additionally, the mining difficulty of Bitcoin Gold resets every block.
Bitcoin Segwit2x ("Bitcoin 2x" or "B2X") is planned to occur in mid-November (in about eight days). It will alter the block size from 1 MB to 2 MB and will keep Segregated Witness active.
Remember that this latest hard fork will be occuring at block 494,784, which will be in mid-November. You can see a live countdown to the fork here.
In order to make sure your coins are completely secure and that you have the most options available to you, follow the steps below.
Withdraw any Bitcoin stored in an exchange to a private wallet, especially if they haven't released a statement on the fork yet.
A Private Wallet is any wallet running locally on your computer or on physical hardware, such that you know the private key. See this release by Bittrex for an example of a fork statement.
Don't make Bitcoin transactions using an exchange starting 24 hours before the hard fork (around block 494,640). Even more importantly, don't make transactions on either chain at least 24 hours after the hard fork.
Bitcoin Segwit2x does not have replay protection. This means if you send coins on the original chain or send coins on the forked chain, you may also be inadvertently sending your coins on the other chain.
Listen to instructions from the Bitcoin community and exchanges regarding splitting your coins so you can transact without worrying about replay attacks. If you're using Electrum as your private wallet, they have a great guide here regarding splitting your coins after the fork.
After you have read and followed the instructions above, you're free to make your own judgements about the fork and transact freely. Good luck!
Thanks for reading,
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image sources: 1, 2, 3, 4, 5
note: The Segwit2x Hard Fork has been called off! See my note in the comments below for added information.
