The best decryption best practice that the administrator should consider is A: Consider the local, legal, and regulatory implications and how they affect which traffic can be decrypted. This is because decryption involves intercepting and inspecting encrypted traffic, which may raise privacy and compliance issues depending on the jurisdiction and the type of traffic1. Therefore, the administrator should be aware of the local, legal, and regulatory implications and how they affect which traffic can be decrypted, and follow the appropriate guidelines and policies to ensure that decryption is done in a lawful and ethical manner1.

* Ping Interval-Specify the interval between pings that are sent to the destination IP address (range is 200 to 60,000ms; default is 200ms).
* Ping Count-Specify the number of failed pings before declaring a failure (range is 3 to 10; default is 10).

A syslog listener is the best choice for deploying User-ID to ensure maximum coverage in an environment with multiple forms of authentication. A syslog listener is a feature that enables the firewall or Panorama to receive syslog messages from other systems and parse them for IP address-to-username mappings. A syslog listener can collect user mapping information from a variety of sources, such as network access control systems, domain controllers, MDM solutions, VPN gateways, wireless controllers, proxies, and more2. A syslog listener can also support multiple platforms and operating systems, such as Windows, Linux, macOS, iOS, Android, etc3. Therefore, a syslog listener can provide a comprehensive and flexible solution for User-ID deployment in a large-scale network. Reference: Configure a Syslog Listener for User Mapping, User-ID Agent Deployment Guide, PCNSE Study Guide (page 48)

The two key exchange algorithms that consume the most resources when decrypting SSL traffic are ECDHE and DHE. These are both Diffie-Hellman based algorithms that enable perfect forward secrecy (PFS), which means that they generate a new and unique session key for each SSL/TLS session, and do not reuse any previous keys. This enhances the security of the encrypted communication, but also increases the computational cost and complexity of the key exchange process. ECDHE stands for Elliptic Curve Diffie-Hellman Ephemeral, which uses elliptic curve cryptography (ECC) to generate the session key. DHE stands for Diffie-Hellman Ephemeral, which uses modular arithmetic to generate the session key. Both ECDHE and DHE require more CPU and memory resources than RSA, which is a non-PFS algorithm that uses public and private keys to encrypt and decrypt the session key123. Reference: Key Exchange Algorithms, Best Practices for Enabling SSL Decryption, PCNSE Study Guide (page 60)