What is the purpose of key exchange in symmetric encryption?

The purpose of key exchange in symmetric encryption is to ensure that only the intended parties know the symmetric key. In symmetric encryption, the same key is used for both encryption and decryption of the data, which means that keeping this key secure is paramount. If an unauthorized party gains access to the key, they can read the encrypted data and potentially impersonate authorized users.

The key exchange process is critical because it establishes a shared secret between two or more parties without allowing anyone else to intercept that key. This is typically done through various secure protocols or algorithms designed specifically for this purpose, ensuring that communication is protected against eavesdropping.

While backup copies are important for data integrity, they are not directly related to the key exchange process. Enhancing the speed of data transfer and encrypting data during transmission are functions of encryption itself, but they don't specifically address the role of key exchange in managing the security of the symmetric key. Therefore, ensuring that only the intended parties have access to the symmetric key is the central focus of the key exchange process.