A trusted computing host is described that provides various security computations and other functions in a distributed multitenant and/or virtualized computing environment. The trusted host computing device can communicate with one or more host computing devices that host virtual machines to provide a number of security-related functions, including but not limited to boot firmware measurement, cryptographic key management, remote attestation, as well as security and forensics management. The trusted computing host maintains an isolated partition for each host computing device in the environment and communicates with peripheral cards on host computing devices in order to provide one or more security functions.