Abstract: Rootkit-resistant disks (RRD) label all immutable system binaries and configuration files at installation time. During normal operation, the disk controller inspects all write operations received from the host operating system and denies those made for labeled blocks. To upgrade, the host is booted into a safe state and system blocks can only be modified if a security token is attached to the disk controller. By enforcing immutability at the disk controller, a compromised operating system is prevented from infecting its on-disk image.

Abstract: A method and system for determining and enforcing security policy in a communication session are provided in distributed systems. Policy encompasses the provisioning, authorization, and access control within the protected environment. Hence, all communication security requirements are explicitly stated through policy. A policy instantiation is constructed at run-time through policy determination. Conditional, abstract, and discretionary policies stated by communication participants are reconciled to arrive at an instantiation. The resulting instantiation is a concrete specification of the mechanisms, configurations, and access control model to be implemented by the session. The semantics of an instantiation are achieved through policy enforcement. The policy enforcement architecture implements session policies through the composition and configuration of security mechanisms using a novel event-bus architecture. Policy is enforced through the observation of and reaction to relevant events.