  Bolted is a new architecture for bare-metal clouds that enables tenants to
control tradeoffs between security, price, and performance. Security-sensitive
tenants can minimize their trust in the public cloud provider and achieve
similar levels of security and control that they can obtain in their own
private data centers. At the same time, Bolted neither imposes overhead on
tenants that are security insensitive nor compromises the flexibility or
operational efficiency of the provider. Our prototype exploits a novel
provisioning system and specialized firmware to enable elasticity similar to
virtualized clouds. Experimentally we quantify the cost of different levels of
security for a variety of workloads and demonstrate the value of giving control
to the tenant.
