Which of the following best describes XKMS?

The correct answer identifies XKMS, which stands for XML Key Management Specification, as a service designed to manage Public Key Infrastructure (PKI) operations using XML. This specification facilitates the process of handling key management tasks, allowing clients to request and manage keys and certificates from a trusted source through XML-based messages.

By leveraging XML, XKMS streamlines communication and processing of cryptographic keys, enhancing interoperability and ease of integration with other web services. This makes it particularly valuable for applications that require secure key management without necessitating a deep understanding of the underlying cryptographic details.

The other options do not accurately characterize XKMS. Generating encryption keys is specific to cryptographic key generation rather than managing existing keys and certificates, which is the core function of XKMS. Securing email communications is covered by other protocols such as S/MIME or PGP, while managing network access typically involves network authentication protocols rather than the specific functions related to PKI that XKMS addresses. Thus, option B truly encapsulates the primary purpose and functionality of XKMS in the context of computer security practices.