Agent Deployment - Agent installation and Multiple Administrative Credentials

Please provide the option when deploying an agent as deployer to specify multiple Administrative Credentials. Consider that on a network you may have both domain based and non-domain based (workgroup) machines. Currently it is my understanding that discovery can only be done with Active Directory based machines. Workgroup or standalone machines have to be done by installing the agent directly on those machines by manual process. Give the discovery agent the ability to scan the network for machines that are candidates for agent installation, and enable us to provide credentials for any / all machines. An alternate method would be to provide the credentials on the Manage...Deployment panel for those machines discovered but not yet installed.