Public Key Infrastructure (PKI) is mainly used for what purpose?

Public Key Infrastructure (PKI) is fundamentally designed for managing keys for encryption, which is essential for facilitating secure communications over networks. PKI provides a framework that includes hardware, software, policies, and procedures to create, manage, and distribute digital certificates and public-private key pairs. This structure enables secure data encryption, digital signatures, and authentication processes.

The management of keys is critical because encryption relies on these keys to lock (encrypt) and unlock (decrypt) sensitive data. Users and systems can trust that the information is only accessible to authorized parties, thanks to the assurance provided by the digital certificates issued within a PKI framework.

While securing online transactions is an important function of systems that leverage PKI, it is more of an application of the technology rather than its primary purpose. The same applies to managing network devices and monitoring network performance, which are not core functionalities of PKI. Instead, they represent different aspects of network management and security that can benefit from encryption and authentication. Thus, the correct answer highlights the essential role of PKI in key management.