Why is blockchain not secure?

Blockchain is not immune to hacking.

blockchain

isn't immune to piracy, but being decentralized gives blockchain a better line of defense. To alter a chain, a hacker or criminal would need control of more than half of all computers in the same distributed ledger (unlikely, but may be explained later). The blockchain was created to be completely immutable, so once data is placed inside the blockchain, it cannot be manipulated.

This means that data stored within the blockchain itself is highly secure. One supposed guarantee of the security of a blockchain system is “decentralization”. If the copies of the blockchain are kept on a large, widely distributed network of nodes, there is no weak spot to attack, and it is difficult for anyone to accumulate enough computing power to subvert the network. But recent work by Sirer and his colleagues shows that neither bitcoin nor Ethereum is as decentralized as you might think.

They found that the top four bitcoin mining operations had more than 53 percent of the system's average mining capacity per week. With the same measure, three Ethereum miners accounted for 61 percent. Blockchain transactions are also protected by cryptography. Each transaction is signed with a private key and can then be verified with a public key.

If the transaction data changes, the signature becomes invalid. As a result, the block is ignored and will not reach the chain. Blockchain technology enables decentralization through member participation in a distributed network. There is no single point of failure and a single user cannot change the transaction log.

However, blockchain technologies differ in some critical security aspects. While the words transparency and public don't sound safe, in the case of Bitcoin it is. Despite the user's anonymity, all transactions on the network are accessible to the public, making it difficult to hack or trick the system. This is a problem both for public blockchains, which do not control who hosts a node, and for private blockchains (also called permissioned blockchains), since data cannot be deleted here.

The cryptocurrency hacks that drive recent headlines are often flaws in places where blockchain systems connect to the real world, for example, in third-party software clients and applications. Without going into too much detail, the longest chain is usually the one that most blockchain pairs support, so the only way to hack consensus protocols is to imitate this majority through a 51 percent attack. IBM Blockchain services and consulting can help you design and activate a blockchain network that addresses governance, business value and technology needs, while ensuring privacy, trust and security. Vitalik Buterin, co-founder of Ethereum, another blockchain system like Bitcoin and Hyperledger, has pointed out that, in fact, there is a “scalability trilemma” in which only two of the three properties can be achieved: decentralization, security or scalability.

It is clear that security challenges, specifically the vulnerability of private keys, must be addressed before the full potential of blockchain technology can be realized. Herein lies the fundamental deficit that undermines the security of blockchain solutions: protecting private keys. But the security of even the best-designed blockchain systems can fail in places where sophisticated mathematical and software rules come into contact with humans, who are skilled cheaters, in the real world, where things can get complicated. As other practical implementations for technology are discovered, blockchains are becoming the main contenders for solving a number of cybersecurity challenges and providing end-to-end security to global institutions.

Many cutting-edge financial firms, for example, have used blockchain to speed up processes and reduce costs without compromising security. But if a miner, or a group of miners, could gather enough resources, they could reach more than 50% of the mining power of a blockchain network. Meanwhile, several states in India are exploring blockchain-based systems to improve information efficiency and improve cybersecurity. A comprehensive security strategy for an enterprise blockchain solution includes the use of traditional security controls and technology-exclusive controls.

The code and the agreements contained in it exist on a distributed and decentralized blockchain network. But what else can you expect from something that has been revolutionizing the world? Let's break down the chain and explain what exactly makes blockchain secure. . .