The Auto Deploy stateless caching feature lets you cache the host's image. The Auto Deploy stateful installs feature lets you install hosts over the network. After the initial network boot, these hosts boot like other ESXi hosts.
The stateless caching solution is primarily intended for situations when several hosts boot simultaneously. The locally cached image helps prevent a bottleneck that results if several hundreds of hosts connect to the Auto Deploy server simultaneously. After the boot operation is complete, hosts connect to Auto Deploy to complete the setup.
The stateful installs feature lets you provision hosts with the image profile over the network without having to set up the PXE boot infrastructure.