<p>Bitcoin is secured through proof-of-work mining using SHA256 as the mining algorithm. Bitcoin Cash uses the same algorithm, so the specialized ASIC hardware used to mine one coin, could also be used to mine the other. </p>

<p>PoW coins are susceptible to ‘<a href="https://bitcoin.stackexchange.com/q/658/63872">51% attacks</a>’, which are possible when a bad actor controls a majority of the network’s hashpower. </p>

<p>So generally, when considering ‘how secure’ a blockchain is, we consider how possible, or likely, it is for a single entity (or a group of colluding entities) to gain control of a majority of the hash power available for a coin. The more hashpower a coin has pointed at it, the more secure we can consider it to be. This is because an attacker would need a larger amount of hashpower under their control in order to enact an attack. </p>

<p>From <a href="https://fork.lol/pow/hashrate" rel="noreferrer">fork.lol</a>, we can see that over the last 7 days, the BTC hashrate has been approx 47.3 exahashes/second, while the BCH hashrate has been approx 1.6 exahashes/second. </p>

<p>By this measure, Bitcoin Cash is <strong>most certainly</strong> not ‘more secure’. </p>

CC BY-SA 4.0
2019-03-23T16:27:01.910Z
2019-03-23T16:27:01.910Z
chytrik
<p>I disagree with Chytrik: The hashrate and the number of miners are not the only factors that affect security. Here are some other factors:</p>

<ul>
<li>Frequency of code review of nodes/wallets</li>
<li>Reputation of the companies who create wallet</li>
<li>The number of nodes in the network</li>
<li>Formal verification of software</li>
<li>How well-documented the protocol is (in long term)</li>
<li>Frequency of breaking changes (and other changes)</li>
<li>Code readability and simplicity</li>
<li>Whether software is signed before signed</li>
</ul>

<p>Which means security is hard to measure.</p>

<p>If you had 1 BTC a year before, and today you open the wallet for the second time and that 1 BTC is still there, miners are not whom to thank.</p>

CC BY-SA 4.0
2019-03-25T00:09:34.773Z
Good points, I agree with this, but I think that for coins that share a mining algorithm, the proportion of hashrate pointed at each network is still quite important. But in any case, even if security is hard to measure in an absolute sense, I think that BTC outdoes BCH for every point you mentioned. Ergo, BCH is not the ‘most secure blockchain’, as per OP’s question.
chytrik
CC BY-SA 4.0
2019-03-24T09:08:11.210Z
2019-03-24T09:08:11.210Z
MCCCS
<p>As Nate mentioned, this is just a marketing statement. Any sane coin would try and promote themselves in this manner. Most are incorrect.</p>

<p>The most basic counter example being that many Bitcoin mining pools have enough hash power to perform a 51% attack on the Bitcoin cash chain. That alone is enough to not qualify it as the "World's most robust" chain.</p>

CC BY-SA 4.0
2019-03-23T15:46:42.483Z
2019-03-23T15:46:42.483Z
Raghav Sood
<p>I found in <a href="https://www.bitcoincash.org/index.html" rel="nofollow noreferrer">https://www.bitcoincash.org/index.html</a> that this technology is 
the world's most robust blockchain but searching for the details that explains why it is so secure I don't find any information. Some one knows a source that probes why this technology is secure and some technical information about the security implemented on it ?</p>

CC BY-SA 4.0
2019-03-23T15:31:44.007Z
Statements like "the world's most robust blockchain" are meaningless marketing fluff and should be ignored.  But you can certainly read about how the currency works and draw your own conclusions about its security.  The main ideas are the same as for Bitcoin, about which much more has been written.  You can browse questions on this site, for instance.
Nate Eldredge
<bitcoin-cash>
Is Bitcoin Cash more secure?
melmansuri
# Is Bitcoin Cash more secure?

(Asked by: username_0 on 2019-03-23)

I found in <https://www.bitcoincash.org/index.html> that this technology is
the world's most robust blockchain but searching for the details that explains why it is so secure I don't find any information. Some one knows a source that probes why this technology is secure and some technical information about the security implemented on it ?

**Tags:** bitcoin-cash

> **Comments:**
> **username_1**: Statements like "the world's most robust blockchain" are meaningless marketing fluff and should be ignored.  But you can certainly read about how the currency works and draw your own conclusions about its security.  The main ideas are the same as for Bitcoin, about which much more has been written.  You can browse questions on this site, for instance.  

---

## 3 answers

### Answer by username_2 on 2019-03-23. Score: 5

Bitcoin is secured through proof-of-work mining using SHA256 as the mining algorithm. Bitcoin Cash uses the same algorithm, so the specialized ASIC hardware used to mine one coin, could also be used to mine the other.

PoW coins are susceptible to ‘[51% attacks](https://bitcoin.stackexchange.com/q/658/63872)’, which are possible when a bad actor controls a majority of the network’s hashpower.

So generally, when considering ‘how secure’ a blockchain is, we consider how possible, or likely, it is for a single entity (or a group of colluding entities) to gain control of a majority of the hash power available for a coin. The more hashpower a coin has pointed at it, the more secure we can consider it to be. This is because an attacker would need a larger amount of hashpower under their control in order to enact an attack.

From [fork.lol](https://fork.lol/pow/hashrate), we can see that over the last 7 days, the BTC hashrate has been approx 47.3 exahashes/second, while the BCH hashrate has been approx 1.6 exahashes/second.

By this measure, Bitcoin Cash is **most certainly** not ‘more secure’.


---

### Answer by username_3 on 2019-03-24. Score: 2

I disagree with username_2: The hashrate and the number of miners are not the only factors that affect security. Here are some other factors:

* Frequency of code review of nodes/wallets
* Reputation of the companies who create wallet
* The number of nodes in the network
* Formal verification of software
* How well-documented the protocol is (in long term)
* Frequency of breaking changes (and other changes)
* Code readability and simplicity
* Whether software is signed before signed

Which means security is hard to measure.

If you had 1 BTC a year before, and today you open the wallet for the second time and that 1 BTC is still there, miners are not whom to thank.

> **Comments:**
> **username_2**: Good points, I agree with this, but I think that for coins that share a mining algorithm, the proportion of hashrate pointed at each network is still quite important. But in any case, even if security is hard to measure in an absolute sense, I think that BTC outdoes BCH for every point you mentioned. Ergo, BCH is not the ‘most secure blockchain’, as per OP’s question.  

---

### Answer by username_4 on 2019-03-23. Score: 2

As username_1 mentioned, this is just a marketing statement. Any sane coin would try and promote themselves in this manner. Most are incorrect.

The most basic counter example being that many Bitcoin mining pools have enough hash power to perform a 51% attack on the Bitcoin cash chain. That alone is enough to not qualify it as the "World's most robust" chain.


---

