As of May 31, 2023, we have updated our Code of Conduct.
29 votes
Accepted

How is segwit2x different from segwit?

SegWit2x is a combination of both SegWit and a 2MB hardfork (to activate three months after SegWit). SegWit2x uses a different 'bit' for signaling (bit 4 instead of bit 1) than SegWit. SegWit (...
Wouter's user avatar
  • 406
8 votes

Where can you see current Bitcoin miners signalling SegWit2x?

Blocks signalling for the SegWit2x, i.e. the New York Agreement segwit activation (BIP91), are setting bit4. This shows up as a '1' in the second to last position of the version field. Blocks ...
Murch's user avatar
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6 votes
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What is the difference between BTC and Bitcoin Core?

Bitcoin Core is a specific implementation of the Bitcoin protocol, specifically the one in the Bitcoin GitHub Repository. It is the evolved version of the original client Satoshi wrote, in C++. It is ...
meshcollider's user avatar
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5 votes
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What happens to my bitcoins if a hard fork occurs?

Technically, the UASF that will go live on August 1st isn't a hardfork (see What is the User Activated Softfork (UASF) proposal? How do its risks compare to hardforks?), but it may have still have a ...
morsecoder's user avatar
5 votes

What was the number of the block in which SegWit got activated? And first transaction?

This is a very old question but probably someone else needs to know the same: SegWit was activated in block 481824 and that block has two p2wpkh txs: ...
lontivero's user avatar
  • 191
5 votes
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Will there be a hard-fork with BTC and B2X?

Will there be a hard-fork between B2X and BTC? Yes, most likely, although it's hard to know for sure. There seems to be enough people who want the 2x fork that it will happen, and there definitely ...
Eric Allam's user avatar
4 votes

When is the earliest we will see SegWit transactions on main net

Nobody can determine the date for that event. SegWit, like every soft fork, requires a majority of miners to enforce the new rules in addition to economically relevant nodes. The initial BIP that ...
Pieter Wuille's user avatar
4 votes

BIP91 Activation Period

It looks like it is actually periods of 336 blocks instead of a rolling window. It is like what BIP 9 specifies, but uses 336 blocks as the window and 269 blocks as the threshold. The windows begin ...
Andrew Chow's user avatar
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4 votes
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Can there be a half segwit, half normal Bitcoin transaction?

Yes, absolutely. Every output can independently be a normal or SegWit output (when using P2SH-embedded SegWit, you can't even tell until it is being spent). Every input can independently spend a ...
Pieter Wuille's user avatar
4 votes
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If Btc2x doesn't have replay protection does that mean all transactions can be automatically replayed in btc2x?

Since 2x has decided not to implement replay protection, transactions will be indeed compatible to both chains. If a transactions is simply broadcast to the other chain, it will enter the mempools ...
Murch's user avatar
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3 votes
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Can someone explain to me all of the scaling proposals?

Segregated Witness (segwit) is a solution which redefines how the maximum block size is calculated (now called block weight) and creates new output types. These segwit output types are given a ...
Andrew Chow's user avatar
  • 66.4k
3 votes

Can there be a half segwit, half normal Bitcoin transaction?

Yes, that is certainly possible. BIP 143 has examples of such transactions. Transactions that spend from both segwit outputs and non-segwit outputs are still vulnerable to transaction malleability.
Andrew Chow's user avatar
  • 66.4k
3 votes

Where can you see current Bitcoin miners signalling SegWit2x?

You can see that information here (SegWit2x is BIP91): https://www.xbt.eu/
Paul's user avatar
  • 361
3 votes

Is the SegWit2X success due to concentration of mining power?

I feel that the existing answers here fail to highlight that while (the collection of) miners have the authority to select the order of transactions, and impose additional validity rules, they do not ...
Pieter Wuille's user avatar
3 votes

How does the Segwit2x fork implement replay protection?

segwit2x temporarily had an opt-in replay protection, but chose to remove it. it is intentional, as part of their strategy to make only one fork survive.
Jonathan Silverblood's user avatar
3 votes
Accepted

Which full node implementation(s) supports SegWit2x?

If I can choose between Bitcoin Core, Bitcoin ABC, Bitcoin XT, and Bitcoin Classic None of these software support Segwit2x. Currently your only choice of Full node software for Segwit2x is btc1.
Andrew Chow's user avatar
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3 votes
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Limit tx to SegWit1x or 2x chain

All transactions would be replayable on both chains even after one was confirmed in a block on one chain, because since both chains start with the same UTXO set, the transactions spending those UTXOs ...
meshcollider's user avatar
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3 votes
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Who decided that segwit2x isn't going to happen?

Key proponents of the New York Agreement have rescinded their support after large parts of the community opposed their initiative for months. Theoretically, a miner could still activate the fork ...
Murch's user avatar
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3 votes

Who decided that segwit2x isn't going to happen?

Though its major proponents have called it off, there's a miner with an unknown (likely less than 10%) amount of hash power vowing to continue: https://cointelegraph.com/news/segwit-death-challenge-...
Daniel's user avatar
  • 31
3 votes
Accepted

How to check if the segwit2x fork was adopted?

Here's an official announcement of the fork having taken place. According to the official website the fork is planned for block 501451 which has indeed occurred about 8 hours ago. The stats of their ...
gosuto's user avatar
  • 712
3 votes
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Segwit transaction size not smaller

You are mistaking virtual size that got introduced with SEGWIT with the legacy size. 166 bytes is the virtual size. 248 bytes is the legacy one. Unfortunately, Blockchain.info shows only the legacy ...
youssef's user avatar
  • 246
2 votes

What is impact of the possible nitwit fork on August 1? Will it double the coins I have?

No, all clients will be compatible until the HF and will mine one chain. If SegWit2x reaches 80% support during a 336 block signaling period, it means that the SegWit softfork locks in and will ...
user51971's user avatar
2 votes

Segwit2x and Trezor

As you can see from an answer given by a Trezor's staff member in this reddit post on 5th October 2017: We will do an official communication once it is clear what Segwit2x is and what is not. ...
salvarico's user avatar
  • 163
2 votes

How will the 2mb hard fork be implemented?

August 1st has nothing to do with BIP 91, nor will segwit become active on August 1st due to either of BIP 148 or BIP 91. The current projected date for segwit to become active (assuming that BIP 91 ...
Andrew Chow's user avatar
  • 66.4k
2 votes

Segwit2x/btc1 block header changes: wipeout protection for SPV nodes?

From following most of what has been going on in the btc1 repository, it is S2x's express plan to take along SPV wallets with their hard fork. Therefore, they are limiting wipeout protection to ...
Murch's user avatar
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2 votes
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Do I need to run a full node before the 2X fork?

Your coins are safe on Trezor, you don't need to run full node for coins unless you want to help mine. If you want to access Segwit2X coin or any other BTC forked coins (in future) asap after the ...
remedcu's user avatar
  • 1,083
2 votes

Can BIP91 cause a chain split?

The minority of miners that do not support BIP91 (and by extension BIP141), could start rejecting blocks of those who are signaling BIP141, thereby creating a different chain. Is that a possibility ...
Andrew Chow's user avatar
  • 66.4k
2 votes
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At the moment SegWit2x forks, will mining be way easier?

No, it will not be easier. The "difficulty" of mining is determined by the difficulty (the value). The difficulty only adjust itself every 2016 blocks, so when the Segwit2x fork happens, the ...
Andrew Chow's user avatar
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2 votes
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Where's the code related to block 494784 for segwit2x?

It is referenced relatively, namely by using the parameter BIP102HeightDelta. The hardfork is 3 months after the block that Segwit was actived and the number of blocks after is equal to 90(days)*144(...
Bjarne Magnussen's user avatar
2 votes
Accepted

Is there an oveview of organizations support of segwit/segwit2X?

First of all, Segwit and Segwit2x are two different things. Segwit has already activated, Segwit2x has not. Please do not conflate the two. https://coin.dance/poli and http://segwit.party/nya/ list ...
Andrew Chow's user avatar
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