We will begin our discussion of how the IVE can extend your network's security to hosts connecting to your network through the IVE by introducing a very powerful tool called Host Checker. Host Checker is essentially an application that is automatically provisioned to clients that connect to your network through the IVE. Host Checker does exactly what its name implies. It ensures that the host that is connecting to your network meets a certain set of criteria before it can gain access to resources. You can deploy Host Checker to end systems in many ways, and as it has with all of its products, Juniper has emphasized granular control and implementation of this feature to empower you to have a wide variety of scalable options for deployment. In this section, we will begin by discussing how Host Checker works and is deployed, and various options and tools that you have at your disposal. We will also spend some time discussing custom Host Checker policies and rules, as well as support for the Trusted Computing Group's (TCG's) Trusted Network Connect (TNC). These features allow you to expand you ability to ensure end-system compliance in just about any way you can imagine with the use of customized checks.