Answers and Explanations

1. D. In x.509, the owner does not use a symmetric key. All the other answers apply to x.509.

2. B and C. A digital certificate includes the Certificate Authority’s (CA) digital signature and the user’s public key. A user’s private key should be kept private and should not be within the digital certificate. The IP address of the CA should have been known to the user’s computer before obtaining the certificate.

3. D. When creating key pairs, PKI has two methods: centralized and decentralized. Centralized is when keys are generated at a central server and are transmitted to hosts. Decentralized is when keys are generated and stored on a local computer system for use by that system.

4. A. IPsec is usually used with L2TP. SSH is a more secure way of connecting to remote computers. PHP is a type of language commonly used on the web. SHA is a type of hashing algorithm.