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)

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)

Device Group Hierarchy
Shared
DATACENTER_DG
DC_FW_DG
REGIONAL_DG
OFFICE_FW_DG
FW-1_DG
Analysis
Considerations:
FW-1 is assigned to the FW-1_DG device group.
FW-2 is assigned to the OFFICE_FW_DG device group.
There are no objects configured in REGIONAL_DG and OFFICE_FW_DG device groups.
The address object Server-1 appears in multiple device groups with different IP addresses. The device groups have a hierarchy, which means objects can be inherited from parent groups unless overridden in the child group.
FW-1_DG:
Server-1 has IP 4.4.4.4, which will be pushed to FW-1 because it is in the FW-1_DG device group.
OFFICE_FW_DG (for FW-2):
Since there are no objects in OFFICE_FW_DG and REGIONAL_DG, FW-2 will inherit from Shared.
In the Shared group, Server-1 has IP 1.1.1.1.