<p>Bcash transactions cannot be replayed on the Bitcoin network, and vice versa, Bitcoin transactions cannot be replayed on the Bcash network. This is called 2-way replay protection. In Bcash's case, it's implemented by the mandatory use of a sighash flag that's invalid for a Bitcoin transaction.</p>

CC BY-SA 3.0
2017-10-09T16:38:13.007Z
This is not what I read in all the tutorials? Am I stupid or is there widespread misconseption about this?
Kristoffer Nolgren
CC BY-SA 3.0
2017-10-09T18:12:24.323Z
2-way replay protection was added very late before BCash's hard fork so some tutorials may be out of date.
alcio
CC BY-SA 3.0
2017-10-24T07:49:24.553Z
The pull request introducing the 2-way replay protection was merged into the code base on Jul 26th, while the fork happened on Aug 1st. See https://github.com/Bitcoin-ABC/bitcoin-abc/pull/30
alcio
CC BY-SA 3.0
2017-10-09T13:58:48.747Z
2017-10-09T13:58:48.747Z
alcio
<p>I had some bitcoin during the coinsplit, so now I have bcash that I want to move.</p>

<p>When I send bcash there is a risk that someone copies the transactions and uses it to steal my bitcoin. Most people recommend moving the bitcoin to a new adress for this. this is not practical for me right now, will it work to just move my bcash to a new adress instead before I send them or will this also allow an attacker to copy the transactions?</p>

<security><blockchain-fork><bitcoin-cash>
How to keep my bitcoin safe when I move my bcash?
Kristoffer Nolgren
# How to keep my bitcoin safe when I move my bcash?

(Asked by: username_0 on 2017-10-09)

I had some bitcoin during the coinsplit, so now I have bcash that I want to move.

When I send bcash there is a risk that someone copies the transactions and uses it to steal my bitcoin. Most people recommend moving the bitcoin to a new adress for this. this is not practical for me right now, will it work to just move my bcash to a new adress instead before I send them or will this also allow an attacker to copy the transactions?

**Tags:** security, blockchain-fork, bitcoin-cash


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## 1 answers

### Answer by username_1 on 2017-10-09. Score: 2 | Accepted answer

Bcash transactions cannot be replayed on the Bitcoin network, and vice versa, Bitcoin transactions cannot be replayed on the Bcash network. This is called 2-way replay protection. In Bcash's case, it's implemented by the mandatory use of a sighash flag that's invalid for a Bitcoin transaction.

> **Comments:**
> **username_0**: This is not what I read in all the tutorials? Am I stupid or is there widespread misconseption about this?  
> **username_1**: 2-way replay protection was added very late before BCash's hard fork so some tutorials may be out of date.  
> **username_1**: The pull request introducing the 2-way replay protection was merged into the code base on Jul 26th, while the fork happened on Aug 1st. See https://github.com/Bitcoin-ABC/bitcoin-abc/pull/30  

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