Public Key
What Is a Public Key
A public key in blockchains is a crucial component of cryptographic systems that enables secure transactions and communication between participants on the network. It is part of a cryptographic key pair, consisting of a public key and a private key. The public key is shared openly and used to receive transactions, while the private key, which is kept secret by the owner, is used to sign and authorize those transactions. The relationship between the public and private keys ensures that only the rightful owner of the private key can approve transactions associated with the corresponding public key, enabling secure and verifiable interactions in the blockchain network.
In blockchain systems, public keys are typically derived from private keys using cryptographic algorithms such as Elliptic Curve Cryptography (ECC). Once a public key is generated, it can be shared freely with other network participants without compromising security. When a transaction is initiated, the sender will encrypt it using the recipient’s public key, and only the recipient, with their corresponding private key, can decrypt and access the transaction details. This process ensures confidentiality and authenticity, which are fundamental to the trustless nature of blockchain networks.
Public keys are also used to create addresses on blockchain platforms like Bitcoin and Ethereum. These addresses, which are shorter, hashed versions of the public key, serve as the destination for sending and receiving assets on the blockchain. Since the public key can be shared openly, anyone can send assets to a public address, but only the individual with the corresponding private key can access or spend those assets. This cryptographic principle allows blockchains to function securely without the need for central authorities or intermediaries.