An embodiment may include circuitry to be included, at least in part, in a host. The host may include at least one host central processing unit (CPU) to execute, at least in part, at least one host operating system (OS). The circuitry may perform, at least in part, at least one operation in isolation both from interference from and control by the at least one host CPU and the at least one host OS. The at least one operation may include user authorization determination and user presence determination. The authorization determination may be in response, at least in part, to indication of physical presence of at least one user in proximity to the host. The user presence determination may determine, at least in part, whether, after the indication has been provided, the physical presence of the at least one user in the proximity to the host has ceased.