The entire purpose of blockchain is to let people share valuable data in a secure, tamper-proof environment. Therefore, the security of the blockchain is critically important. As we discussed in the Hard Forks and Nodes sections of Blockademy, there are three main participants involved in securing a decentralized network for the blockchain ledger. The participants include miners, developers, and full node users. All three play a vital role in the security of the blockchain they use.
There are two important features responsible for creating a tamper-proof blockchain. These two components are a cryptographic fingerprint and a consensus protocol.
As you may recall, a cryptographic fingerprint is more commonly known as a hash. A blockchain is formed by linking together individual blocks of transaction data. To prevent fraudulent transactions, the blockchain only contains validated transactions. These validated transactions are a series of encrypted letters and numbers, known as a hash.
Hashing takes a considerable amount of time, computing power and energy to successfully complete. Therefore, the miner who conducts the hashing will receive a cryptocurrency reward. The crypto reward will only be triggered when the hashing was completed, and the block was successfully added to the blockchain.
Nodes are responsible for verifying that the miner’s hash matches its block. If all nodes are in agreement, they each update their copy of the blockchain with the new block. This process is known as “consensus protocol.”
Hashing, along with the consensus protocol is what makes the blockchain immutable. Immutable means “unable to be changed.” When a block has been verified and added to the blockchain, changing the block is virtually impossible.
Brief Summary of Blockchain Security
- The main purpose of blockchain is to allow users to share sensitive information securely.
- Creating a tamper-proof blockchain involves hashing and a consensus protocol.
- Blockchain only contains validated transactions.
- These transactions are validated by miners.
- For their work, miners receive a crypto reward.
- Nodes are responsible for verifying that the miner’s hash matches its block.
- If all nodes are in agreement, they each update their copy of the blockchain.
- This process is known as “consensus protocol.”
- Hashing, along with the consensus protocol is what makes the blockchain immutable.