What is the first step in the exchange of information for public key cryptography?

In public key cryptography, the first step of the information exchange involves the computers exchanging their public keys. Public key cryptography relies on a pair of keys - a public key that can be shared openly and a private key that must be kept secret. When two parties want to communicate securely, they begin by sharing their public keys.

This enables them to encrypt messages without needing a shared secret beforehand, as anyone with the public key can encrypt messages that only the holder of the corresponding private key can decrypt. By using public keys for encryption and private keys for decryption, secure communication is established. The process effectively lays the foundation for secure exchanges, thus highlighting the critical role of public key exchange in ensuring data confidentiality and integrity in digital communications.

In contrast, exchanging passwords or establishing secure connections may occur in different contexts and not as the initial step in public key cryptography. Sending private keys, however, directly contradicts the principles of public key cryptography, as these keys are meant to remain confidential to maintain security.