Blockchain data is encrypted so that only the user with the correct key can access it. Each block in the chain contains a hash of the previous block, so it is not possible to change the data in a blockchain without changing the entire chain.
In order to give someone access to your blockchain data, you need to provide them with your public key. They can then use this key to encrypt the data they want to send to you. Only you, with your private key, can decrypt the data.
This process of encryption and decryption is known as asymmetric key cryptography. It is a very secure way of sharing data, as it is virtually impossible for anyone to decrypt the data without the key.
If you want to give someone access to your blockchain data, you can do so by providing them with your public key.
Other related questions:
Q: How is authentication done in blockchain?
A: There is no one-size-fits-all answer to this question, as the method of authentication will vary depending on the type of blockchain being used. However, some of the more common methods of authentication used in blockchain systems include digital signatures, biometrics, and Public Key Infrastructure (PKI).
Q: What is permission based blockchain?
A: A permissioned blockchain is a type of blockchain where access to the network is restricted to a pre-approved set of participants. In contrast, a permissionless blockchain (such as Bitcoin) allows anyone to join the network.
Q: How do you define a transaction in a blockchain?
A: A transaction on a blockchain is a digital record of an exchange of value between two parties. Transactions are verified and recorded on the blockchain through a process known as mining.
Q: What is the proof of work in blockchain?
A: There is no one definitive answer to this question, as the proof of work algorithm used in blockchain can vary depending on the particular implementation. However, in general, the proof of work algorithm is designed to ensure that only valid transactions are added to the blockchain, and that it is computationally expensive to add new blocks to the chain. This ensures that the blockchain remains secure and tamper-proof.