Bitcoin Forum

I get that blockchains enable immutable data to be recorded, so that I suppose hackers can't delete or write over data on the block.
But what are the other benefits of blockchain for security? I mean, you could make a distributed secure database that doesn't need blockchain right?

Bitcoin's uses blockchain to keep track of bitcoin ledger in real-time. I don't think there's any other method for doing it, While keeping the system with no need for a central authority to determine what time is it and what has written on the ledger until now.

So what does it mean.

Imagine your bitcoin node stops working at some time for one day. And the next time it starts. It knows the ledger until yesterday. There's a network of nodes running on the internet. It tries to connect to one or more. And ask what happened. You can't trust strangers. So bitcoin's blockchain is here to help.
 
The function time is proof-of-work. It's designed to find a block every 10minutes. Which has a special feature, It can rollback in time (It's very UN-efficient, 51% attack can be done with this feature).
Each block contains a set of valid transactions. By attaching the previous block (-10min) to new block with proof-of-work function. blockchain is formed.

You can make a "distributed secure database" (they already exist), but you can't make one in an environment where you don't trust the participants. The advantage of a blockchain is that anyone can participate.

Precisely. It all depends on the use case.

Blockchains shine when it comes to storing transactional data in a public ledger that anyone can read / write to, ie. an adversarial environment. If you are operating within a trusted environment, ie. one where the permission levels of each user is centrally administered (eg. an internal company database) other solutions will fit the bill much better.

Being a sort of distributed database is not what makes blockchains special, it's that it allows full public read and write access while remaining reasonably secure.

Two major factors that ensure security are control and accessibility and not necessarily the immutable ability of the data itself because when those two are compromised the immutability can no longer be trusted and that is what makes blockchain more beneficial than databases.

On control, for database, it either needs to be centralised in a location no matter how decentralised the model that is being practiced. For example Google databases might be spread across the world but still will be in a location that could be compromised and control in the hands of those who are in charge. But for blockchain this is eliminated as control is in the hands of several individuals which means control cannot be abused for whatever purpose.

The accessibility is the intriguing part in that you don't need approval of the initiator of the transaction or data to see and verify if its there. Today, for anybody to get the information about your balance they either need your express approval or court warrant to do that but for blockchain, its just to easy and could not be doctored as several people will be performing the check without approval.

What make from blockchain a secure infrastructure is the management from double spends. As we know you can doublespend the same coin, but only one of them will confirm, and that's what make the chain legit.

Some months ago in Mexico was a crazy hack to banks, and what the hacker did was a double spend with the SPEI system. The problem about that hack was that both transactions confirm letting the hacker create money from no where. That represent a $15 millions lost for banks and that would never happen with blockchain.

You could make a distributed secure database.
But you wouldn't be able to create a distributed secure trustless database with no one in control of and no single point of failure.

The blockchain itself does not secure anything.
It is the combination of multiple technologies which makes the use of a blockchain very beneficial. Especially for a lot of people extensively distributed.
A single company with a few central buildings wouldn't benefit from a blockchain in that way.

Blockchain's purpose is not only about security but also about transparency of the recorded transaction. The transparency of each recorded transaction is one of the best things this technology has given to us as it is like a irreversible public ledger. This technology is also inexpensive to audit and will take less time to verify unlike having your own "secure database" where you still need to worry about other costs not to mention its system reliability might not be good. That is why a lot of companies are already exploiting the idea of this blockchain technology and turning them into patented technologies like how Walmart successfully patented the blockchain technology on a system for storing medical records.

but it definitely  could be some problems with audit in some countries right?

That is right. The advantages of blockchain is that every one is free to participate and involve in. If there is a system security for blackchain users means that it limits and out of the base and foundation of blockchain. The security is on the users itself, while every user keep their account save and doesn't give any important information of the accounts, it will be very safe. 

Until now there have been many investors using Bitcoin which is well-known for its reliable Blockchain technology on transactions, because the blockchain system records all transactions on the global network, so far it may be difficult to hack, but there are new digital currencies that don't use the Blockchain system but using a tangle system, this system is a new distributed ledger architecture, each transaction in this system refers to the two previous transactions, the reference to this transaction as an agreement, with this transaction ensuring that both transactions and tangle apply and comply with the protocol.

I believe that some of you missed the fact that what makes a blockchain secure and special like the Bitcoin blockchain is proof of work. Creating a "blockchain" for the sake of having it called a "blockchain" is moronic.

Yes Proof of Work is the major security feature and must be the basis of the technology's name but in terms of digital currency, the process of "creating blockchain" and the nodes where the "blockchain" was being stored are working together to provide the "advertised" security.
POW creates blockchain, nodes are hodling/verifying blockchain; blockchain is still a logical choice of term. (one more time: blockchain)

That's just terminology, it still depends on how people define "blockchain".
In applications other than crypto, IMO, they can call it whatever they want.

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There's only one way I can answer this: It's an option, not really necessary to all things that require security.

Blockchain is a data structure that enables the creation of a digital ledger of transactions and shares it within a distributed network of computers. It utilizes cryptography to allow each participant on the network to use the ledger in a secure way without a central authority.

Once a block of data is recorded and placed on the Blockchain ledger, it’s extremely hard to change or remove. Blockchain can be hacked in theory (it would take decades and a supercomputer), but in reality, it’s impossible.

So, in my opinion the blockchain is needed for security.

If hackers can get into your system and have permissions to modify your data, the system has already failed. Even if hackers can't rewrite blocks, they can steal, delete or encrypt your data. Besides, many of those private blockchains are aiming to be editable, so hackers might even be able to modify such blockchains. I know very little about software engineering, but I don't think that blockchain is a revolution in data integrity, services have managed to keep their databases intact without blockchain for decades.

Of course it's needed, instead of storing information in one place, you store them across the entire network of computers. You can also verify whether signatures have changed or not. Users already mentioned much.
To sum up, blockchain adds an extra layer of protection to everything, that's the reason why even goverments are going to implement it. Currently it's possible to register land titles by using blockchain.

Then what is a blockchain? Is Google drive a blockchain? Is Amazon AWS a blockchain? Twitter, Facebook, Instagram?

If there is no agreed upon definition then "blockchain" is nothing more than a term used to join the bandwagon. Anything can be a blockchain according to your belief, which is also moronic.

Haha, that clearly not what i mean.
That's why I hate Terms, a person may know what the "thing" is, but he may be unaware of what it is called.

I mean IMO, the blockchain technology can be called other than "blockchain" if it isn't applied to digital currencies.

But then that will bring us back to my previous post where I was asking "what is a blockchain?". Does the unquestionability of bringing consensus, or the "truth", to a "blockchain" have to be secured by proof of work? Because for me it has to.

Plus you talk about some applications that use "blockchain" that are not cryptocurrencies. Do you believe that they are using a "blockchain"? How would you define that "kind of blockchain" then?

That's the problem though, the label "blockchain" is slapped on pretty much anything that even remotely fits the bill with total disregard of existing expectations in terms of security and permissionlessness.

Obviously language is always flowing, as is terminology, but if you dilute the meaning of a term too much it ceases to transport information.

Worse still, if a term has a (more or less) concrete definition in one context (eg. "a blockchain is a permissionless, distributed ledger secured by a decentralized consensus algorithm") but no concrete meaning in another context (eg. "blockchain is the magical solution to everything that is wrong in the world") using it as a fraudulent label becomes trivial.

Sure, the misappropriation of technical terms towards meaningless marketing-speak is nothing new, but at least to me it seems like "blockchain" is one of the worst offenders yet.

We may be moronic to call blockchain "blockchain" but the fact that even if is wasn't called POW/mining/TheMatrix or something, the information about Proof of Work wasn't been disregarded.
That's how Terminology works and I hate it (Honestly, I'm bad at remembering names).

Okay, let's just stop there.
That's your opinion and you expressed your point, I'm not against it.

We're getting off topic.

If Proof of Work was not disregarded, then would you agree with me when I say that "those claiming to use a blockchain without Proof of Work is not a real blockchain?"

Plus this is not off-topic. It is Proof of Work that secures the Bitcoin "blockchain".

is blokchain needed for security?
yes of course, because the Blockchain System does not use a third party as a center, but uses many parties or computers that are spread on the network itself. This will make irresponsible people difficult to enter the system and have interference that is not possible.

Yes block chain is immutable and make a distributed secure database without block chain is like been no sunshine and rain because a lot of  internet users used a node of the network records and corroborate each transaction data. So, the best distributed secure database is by making use of block chain.

Block chain is a powerful and secure network. In terms of security blockchain provides the solution to identity authentication which was the answer to reduce fraud, crime, fake document, breached accounts and making sign on going through seamless which is why some banking sector are captivated by it. However, it can be use during election for counting genuine vote either. There fore a secure database is incomplete without block chain.

On blockchain each full node is not dependend from a centralized service. The technologies of the blockchain are not new. We had cryptography already and p2p networks. The combination of all those technologies makes blockchain so successful, unique and secure. We will soon see, that Blockchain will take an important part in our personal and business life.

This is the typical canned response. But what secures the blockchain? What makes it hard for "bad actors" from colluding? The answer lies in how Bitcoin works and why it works, and once you deeply understand it, you will start saying "Bitcoin, not blockchain".

This depends on most networks which utilize a blockchain, but not on all.

There are a lot of projects with either a 'permissioned' blockchain, which does only allow participants based on some properties, decided by a central authority.
Or projects which 'seem' to be decentralized, but in fact are extremely centralized (e.g. NEO).


While a blockchain only is useful and necessary in a decentralized and trustless network, a lot of projects are just using it as a buzz word to attract more user / investors.
It is not the 'blockchain' but the network topology which makes a network/system decentralized.