If You Own Bitcoin, Bitcoin Cash (Or Any Other Cryptocurrency) You Should Read This

in #bitcoin3 years ago

I'm not a big fan of FUD, on the contrary, I try to keep a balanced perspective and make my decisions by taking into account as many factors as I can. So please don't take this article as FUD, because it isn't. It's a real possibility and, if you keep some cryptos in your portfolio, you will be affected.


Bitcoin Cash is a fork of Bitcoin. It has a bigger block size and that's all it has compared with Bitcoin. More importantly, it has the same hashing algorithm as Bitcoin. You'll see down the road why this is important.

Bitcoin is supported by a group of developers, called Bitcoin Core. Bitcoin Cash is supported by a group of miners (many from China) and a few public persons. I won't be talking about the moral compass of the BCash supporters, because this is not about that. I do have my opinions, though, but I won't make them public now, this is purely technical.

Potential Danger

Because Bitcoin and Bitcoin Cash share the same hashing algorithm (and mining equipments), and because Bitcoin Cash has only 10% of the total hashing power, there is a real danger of a 51% attack.

What is a 51% attack?

In Proof of Work algorithms, transactions are validated after solving a difficult mathematical problem. The one with the most calculation (hashing) power wins. So just because there is at least 90% more hashing power outside the BCash ecosystem, ready to step in at any time, it means a single player can take control over the blockchain.

Now here's where it can get tricky.

The attacker will not control all transactions, openly and publicly. Instead, he will try to mine an alternative blockchain branch, while still making transactions on the main branch. Because it has more hashing power, his alternative branch will become in time, the longer one.

At some point, after he sold his coins in the main branch, he will switch the branches. Now the longest branch - the one he secretly mined - will be the public one. All past transactions will be vanished. It will look like he never spent his coins.

This is a very, very simple explanation, but I urge you to go through this article and read it a few times. It was the reason I decided to write this article.

The Implications

This is not a political article and I'm not taking sides. I don't even own Bitcoin or Bitcoin Cash and I am, as you may know, long term bearish towards Bitcoin as a token, but bullish on the blockchain technology pioneered by Bitcoin. I'm all for appcoins like STEEM (obviously).

This is purely from a technical perspective.

If such an attack is conducted and if it succeeds, it will send poisonous ripples in the entire crypto market. It will be Mt. Gox again. Given the amount of money in the markets right now, it will probably be a few orders of magnitude bigger than Mt. Gox.

I just think this is something you should be aware of.

I'm a serial entrepreneur, blogger and ultrarunner. You can find me mainly on my blog at Dragos Roua where I write about productivity, business, relationships and running. Here on Steemit you may stay updated by following me @dragosroua.

Dragos Roua

You can also vote for me as witness here:

If you're new to Steemit, you may find these articles relevant (that's also part of my witness activity to support new members of the platform):


It’s scary itself just investing then you add so many other dangers

that's life :) or the journey of it, cough, cough :)

:)))))))))))))))))) that was hilarious

Thanks for this useful update @dragosroua.

After reading your post, I am really frightful now. Who knows if steem could also be attacked like this?

STEEM cannot be attacked like this :) It uses a different minting algorithm, called DPoS (the whole witness thing voting, you know?). But being a crypto, it will also be impacted by the negative sentiment.

Core fundamentalists can initiate hashrate attack on more weaker BCash. It could be done by one of the major pools singlehandedly.
That's why I won't buy BCH for more than 20 mbtc. Bitcoin Gold seems even stronger.

In such a scenario, the entire market, even the safest of coins, are going to take a big hit. Market cap will squeeze and a lot of progress will be undone.

Does being in USDT help in such a case?

USDT is not a cryptocoin in true sence.
Trust and bilieve in one particular coin give it value. ANd trust is quite an ephemerial thing.

SBD (when it returns t0 1 USD peg) is a better option IMO.

I was thinking of SBD as well but it has broken the peg and I don't see why it won't go too lower than pegged amount. Nonetheless, with +-0.10$ fluctuation, SBD can be a really good option.

Sbd cant go lower than peg. If does you will be able to buy steem with 1 sbd = 1 usd at platform and sell for more sbd on exchange.

SBD isnt supposed to be pegged to 1 us dollar. it simply means that 1 SBD is worth a minimum of 1 usd worth of steem. 2 different concepts. if you read the steem whitepaper this is what it says.

so, its not pegged to 1 usd. its just supposed to be worth a minimum of 1 usd of steem.

try bitusd

just take profit now and then, don't be 100% crypto

That took me to zero in 2017. Not a good trader at all.

I mean sell 1% every week while things are reaching new all time highs...
Take a look at decentralized exchange, I am trying OpenLedger.io,
instant deposits of steem, and low trading and withdraw fees

Thanks. That's a good suggestion. Cashing out a little chunk every now and then. If such an attack happens and market crashes, that withdrawn money would come very handy to buy coin at their lowest.

How long can it take for this attack to happen? Any ideas.

You mean how long the attacker wants to hold the secondary chain hidden? Nobody knows. The actual takeover in terms of hashing power can happen instantly.

That's what I wanted to know. Instant take over rings some alarm bells for me. Next question though. Is it technologically possible to prevent it from happening?

From a technical point of view, no. Technically speaking, this is a Bitcoin fork, which uses Bitcoin hashing power. So, technically speaking, it can happen.

That means that PoS coins like steem can't be affected by this kind of attack, not event theoretically, right?

yes but bitcoin is still the ocean everything floats on so whenever it crashes it takes any coin with it, whenever there are bearish days on the market out of the 1000++ currencies only 5-10 are on a upward trajectory, to contrast whenever things are business as usual there are 50-100 coins on the negative for the day

because bitcoin (and ethereum as for now) is a household name.
Not for very long in my opinion.

yes, that's true.

PoS has its own set of weaknesses, but a a 51% attack is not part of it. Steem is DPoS, which is a bit different.

I will always stick with who ever has the best developers. I am going to keep all forks until I understand it better don't want to miss out on a new improved version

Thankful for the warning. Good to be aware of this.

Bitcoin and Bitcoin Cash are far too centralised in my viewpoint, just a few people in control of them both.

ohhhhh that's a knowledge for me. i did no know about it, now after reading your article i am able to understand the whole scenerio. and i am lucky that i am steemian and i have steem.
Thanks @dragosroua.
Steem on.!

he was faster than me with less than a second...


Thank You for this information, I was totally unfamiliar with these concepts!

Thanks so much for this warning and information. Is there any way to protect against this type of attack?

diversification, probably, but even in this case, the negative waves send in the entire crypto world will affect the value of other assets.

in an ideal world, exchanges shouldn't show support to vulnerable coins, but they do, because money.

because not only money but extra money and people are greedy, as it stands bch wasn't even a market cap not too long ago now it's a couple of billions, why? probably the new bitcoin train and hype as always ....

Yes, that would cause large negative ripples across the entire crypto market.

I see, I was unaware of the dangers of bitcoin cash, although i knew about the 51% attack exists, I thought that was a long overcome danger for bitcoin, i see now I was wrong, thanks for bringing this matter to my attention.


that's what someone crashing the market would say :D

thnx for explanation i saw this 51% on bitcoin talk but there wasnt details only panic, here is more details and link to source:) so bitcoin gold got same hashing as this 2 too?

Staying diversified as you said helps mitigate these risks. I'm currently allocating more and more into Steem; I see a VERY bright future for us. Cheers!

Yeap, that's a safer approach. But if this happens, the entire market will be affected.

I agree, we'll see a lot of panic selling. If that does happen, I'll be backing up the truck into Steem :)

I personally think a 51% attack is close to impossible to pull of Even on bitcoin cash, cause even if the hashing power only is 10% of bitcoin I think it’s still a lot. I do think this is a big possibility with a lot of the smaller coins tough, and it’s definitely something everyone dealing in crypto should be aware of!

well, stranger things have happened...

Indeed^^ diversification of risk is always smart!

That is a big mess in my mind, could have been worse, although not sure by what magnitude, I do think nothing has hit yet, but for this year there was two successful forks and segwit shit and even some potential future bitcoin forks were added to exchanges :D how mad can you get :D

@dragosroua I have like 10 cents in Bitcoin Cash and no Bitcoin, do you think I should worry ??

I was going to say that we'd probably notice if 51% of BCash's hashes disappeared from the Bitcoin hash rate, but Bitcoin seems to be +- 1500 Phashes a day and BCash peaked at 2500 Phashes total. We wouldn't even notice. Has a takeover like this ever happened before? Back in the old days to demonstrate that it actually works?

Saya sangat menyukai posting anda.... 👉👌👌👍👍👍👍👏👏👏👏

the article is good. how your prediction about the 2018 steam development going forward @dragosroua

Thanks for sharing and i think all who are in the cryptos should read this

It was expected, bitcoin technology, opened the way to the cryptos but it is obsolete, and more time more possible attacks or vulnerabilities will appear, for that reason coins like IOTA, I consider that they are great initiatives and it is an advance in the correct direction, despite the problems that is presenting in the last months.

I do not know about the attack of 51% thanks to @dragosroua, it is something that I will take into consideration, now that I am venturing into the world of cryptos.

Most coins are prone to 51% attacks. POS coins can be attacked by 51% holding.

Very important article that all of us need to know. Thanks for sharing the information with us.

I read about merged mining before and it done on coin with same algorithm so can people mine bitcoin and bitcoin cash the same time?

thanks for the important info

I am incline to believe that some people currently are master mining the 51% BCH attack as we speak. If I understand correctly they have to be mining with more than 51% of the current hash rate and they decided to say start a new chain at the very beginning and put in a hashing rate twice or more than real BCH hash rates they will be catching up at half the time. To do it three folds or more cuts the time even more. Who is not to say this can not be done?

A lot of the commenters made good points that other smaller altcoins can be affected. This is disappointing to here because in decentralized world all coins start at zero hashes. So to have such an easy way to ruin POW coins makes this technology obsolete. The growth possibility for any coin that has not been established for many years would never see the growth like btc. I wonder if programmers have developed math difficulty algorithms that can stop a 51% hash attack. That type of coin can be prove it worth in value beyond any other POW coin.

Good info, but isn't the fact that cryptos in general are becoming more and more mainstream, BTC and BCH being some of the most well known, kinda work against such an attack? Not saying it isn't possible, just harder to pull off.

Thanks for awaking about such thing

articles are very good and also very useful @dragosroua

This is about bitcoin cash, not bitcoin. I know you don't like bitcoin but ...
... it will rise again, what to do? :-)

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