Which action is performed when the administrator configures the global settings for an IPsec VPN?

When configuring the global settings for an IPsec VPN, multiple critical actions are undertaken to ensure secure data transmission. The selection of the pre-shared key is essential as it serves as a shared secret used for authentication between two endpoints in the VPN. Without this key, the devices cannot establish a secure connection.

Defining encryption methods is likewise a pivotal step in establishing an IPsec VPN. This involves selecting algorithms that will encrypt the data packets during transmission, ensuring that the information remains confidential and protected from unauthorized access while traversing through the network.

Controlling the NAT traversal behavior is also included in the global configurations of an IPsec VPN. NAT (Network Address Translation) can interfere with VPN connectivity, and configuring how NAT is handled helps maintain a stable and operational VPN connection, especially when dealing with devices behind NAT routers.

These actions collectively enhance the security and functionality of the IPsec VPN, making it possible to establish secure connections between different networks. Therefore, the assessment that all these elements are part of the global settings configuration is accurate, reflecting the comprehensive approach needed to set up a secure IPsec VPN.