The vSphere Client architecture enables administrators to manage vSphere environments of varying scale and complexity with a single user interface. It supports environments ranging from a single vCenter Server with an embedded Platform Services Controller to a number of vCenter Server instances in Enhanced Linked Mode or Hybrid Linked Mode.

The user interface component runs in a browser and manages the HTML5 views presented to the user. The user interface communicates with the vsphere-ui service, requesting HTML and Javascript files and vSphere inventory data, and authenticating as needed. The user interface also manages a sandbox for each active plug-in, and provides client library services to the plug-in user interface.

The vsphere-ui service is an OSGi Java application server that runs on every vCenter Server node. The vsphere-ui service communicates with all of the services provided by vCenter Server and the Platform Services Controller, by using a variety of API styles and protocols. The vsphere-ui service maintains an authenticated session connection as a client of each of the services.

The vsphere-ui service also provides REST and Web Sockets APIs to the vSphere Client user interface running in the browser. The service supports authentication for users of the vSphere Client by redirecting the browser to a login user interface provided by the VMware vCenter Single Sign-on service running in the Platform Services Controller.