Packer communicators are used to upload files and execute scripts when creating images. The two most common communicators are: ssh – An SSH connection will be established to the machine. This communicator is used by Linux winrm – A WinRM connection will be established. This communicator is used by Windows. OpenSSH is available as an Optional Feature in Windows 10 (version
Source: Packer – Use the SSH communicator for Windows images – ivobeerens.nl