Which component provides centralized management for security and network of multiple ESXi hosts?

The component that provides centralized management for security and networking of multiple ESXi hosts is vCenter Server. This application is essential in a VMware environment, particularly for managing clusters of ESXi hosts. It allows administrators to manage resource allocation, monitor performance, and configure security settings across multiple hosts from a single interface.

vCenter Server facilitates critical functions such as vMotion, which enables live migration of virtual machines, as well as Distributed Resource Scheduler (DRS) and High Availability (HA) features. With vCenter, administrators can enforce consistent security policies across all managed hosts, ensuring that the environment remains secure and compliant.

In contrast, VMware ESXi serves as the hypervisor and does not provide centralized management capabilities; it is focused on hosting virtual machines. VMware Horizon is a platform for desktop and application virtualization, not primarily for managing ESXi hosts. The vSphere Web Client is a tool for interacting with vCenter Server but does not itself provide centralized management; it is merely the interface for managing various features that vCenter Server offers.