Embodiments are directed to enrollment of an endpoint device in a secure domain. An enrollment request is sent to a delegated registrar (DR) device to initiate a trust-establishment procedure with the DR device to establish initial connectivity and an initial symmetric key to be shared between the DR and the endpoint device. The DR device provides to the endpoint device limited-use credentials for group-access key establishment, and group connectivity parameters for accessing a group administrator (GA) device. The endpoint device and the GA device perform a group-enrollment procedure in which the endpoint device provides the limited-use credentials to the GA device and receives, from the GA device, the group-access key.