Rethinking Isolation Mechanisms for Datacenter Multitenancy


V. Gandhi and J. Mickens, “Rethinking Isolation Mechanisms for Datacenter Multitenancy,” in HotCloud, Boston, MA, 2020.

Date Presented:



In theory, trusted execution environments like SGX are promising approaches for isolating datacenter tenants. In practice, the associated hardware primitives suffer from three major problems: side channels induced by microarchitectural co-tenancy; weak guarantees for post-load software integrity; and opaque hardware implementations which prevent third-party security auditing. We explain why these limitations are so problematic for datacenters, and then propose a new approach for trusted execution. This approach, called IME (Isolated Monitor Execution) provides SGX-style memory encryption, but strictly prevents microarchitectural co-tenancy of secure and insecure code. IME also uses a separate, microarchitecturally-isolated pipeline to run dynamic security checks on monitored code, enabling post-load monitoring for security invariants like CFI or type safety. Finally, an IME processor exports a machine-readable description of its microarchitectural implementation, allowing tenants to reason about the security properties of a particular IME instance.


Last updated on 04/25/2021