Segwit2x Definition
What is SegWit2x?
SegWit2x is the second half of the New York Agreement to increase Bitcoin’s block size. It is a combination of the original SegWit update and a proposed 2MB hard fork of the Bitcoin blockchain.
SegWit2x was suggested because the first SegWit didn’t adequately address the blockchain scaling problem. The hope was that by increasing Bitcoin’s blockchain to 2MB, miners could process transactions faster and reduce blockchain bloat and transaction backlog.
How SegWit2x is different?
SegWit2x differs from its predecessor in three key ways:
- SegWit2x wasn’t proposed by Bitcoin Core, the blockchain’s main development team. SegWit2x still hasn’t been endorsed by them.
- SegWit2x is more of a patch than a new upgrade like SegWit was. It builds off of SegWit, rather than starting an update from scratch.
- Though SegWit could have theoreitcally increased the block size by four times, it actually kept the block size constant at 1MB and shrunk transaction size. SegWit2x proposed to double Bitcoin block size to 2MB.
The hard fork was slated for implementation on November 16, 2017, but was cancelled because of lack of consensus. The hash rate of miners supporting SegWit2x has dropped below 10%, and all nodes running the software are permenantly stalled.
Though SegWit2x failed, its potential implementation caused a civil war of sorts between the following parties:
| In Favor of SegWit2x | In Opposition of SegWit2x |
| Many of Bitcoin's larger mining pools who would benefit from increased block size and quicker transaction settlement | Individual node operators and users who wanted to preserve the integrity of the network |
| Bitcoin startups like Coinbase, BitPay, and Blockchain | Several blockchain businesses including Bitrated and Bitonic |
| Developers including Gavin Andresen, the former lead maintainer of Bitcoin Core | A large majority of the current Bitcoin Core developers who currently maintain the software. |
There was worry that the network would split because of SegWit2x, but this hasn’t materialized, and it likely never will.