Multiple Independent Levels Of Security Research Articles

Cybersecurity of Railway Network Management and Partitioning

The railway transport infrastructure ensures the transfer of large numbers of people and cargo every day. The importance of the railway in terms of ensuring the serviceability of the territory makes it a critical infrastructure. We can observe the development of the use of IT technologies on railway, as in all areas of the human system. The management of the railway as a physical system needs to be superseded by management of the railway as a cyberphysical system. The railway infra-structure has a large area of attack in both, physical space and cyber space. Multiple Independent Levels of Security (MILS) can meet the high system security requirements. The MILS is a high-assurance security architecture based on the concepts of separation and controlled information flow. The article discusses the possibilities of using the MILS platform in the data communication system and the control system of the railway. Keywords: Cyber Physical Systems, Critical Infrastructures, Multiple Independent Levels of Security

Secure Separation of Shared Caches in AMP-Based Mixed Criticality Systems

The secure separation of functionality is one of the key requirements particularly in mixed criticality systems (MCS). Well-known security models as the multiple independent levels of security (MILS) aim to formalise the isolation of compartments to avoid interference and make them reliable to work in safety critical environments. Especially for in-car multimedia systems, also known as In-Vehicle Infotainment (IVI) systems, the composition of compartments onto a system-on-chip (SoC) offers a wide variety of advantages in embedded system development. The development of such systems implies often the combination of pre-qualified hardware- and software components. These components are CPU subsystems and operating systems, for example. However, the required strict separation can suffer due to the pre-qualified and therefore not reconfigurable hardware components. Particularly, this is true for shared cache levels in CPU subsystems. The phenomena of interference in the concurrent usage of shared last-level caches, are exploitable by adversaries. Therefore, this article identifies the attack surface and proposes a mitigation to prevent from the intentional misuse of the fixed cache association. Generally, the solution is based on a suitable mapping scheme in the intermediate address space of an asymmetric multiprocessing environment which implements the MCS. Furthermore, we evaluate the strength of the approach and show how the solution contributes to a separation property conformal system.

Design, implementation and verification of MILS systems

SUMMARYSafety‐critical systems are used in many domains (military, avionics, aerospace, etc.) and handle critical data in hostile environments. To prevent data access by unauthorized subjects, they must protect and isolate information so that only allowed entities can read or write information. However, because of their increased number of functionalities, safety‐critical systems design becomes more complex; this increases difficulties in the design and the verification of security functions and potential error in their implementation. The multiple independent levels of security (MILS) approach introduces rules and guidelines for the design of secure systems. It isolates data according to their security levels, reducing system complexity to ease development. However, there is no approach addressing the whole development of MILS systems from high‐level specification (application components with their security levels) to the final implementation (code that executes application functions and provide security mechanisms). This paper presents a complete development approach for the design, verification and implementation of MILS architectures. It aims at providing a complete framework to build secure applications based on MILS guidelines. We describe security concerns using a modeling language, verify security requirements and automatically implement the system code generation techniques and a MILS‐compliant operating system that provides security functions. Copyright © 2012 John Wiley & Sons, Ltd.

Policy-Based Security for Wireless Components in High Assurance Computer Systems

To enable the growth of wireless networks in high assurance computer systems, it is essential to establish a security engineering methodology that provides system security managers with a procedural engineering process to develop computer security policies. Our research demonstrates how wireless communication technology is deployed using the Multiple Independent Levels of Security (MILS) architecture for high assurance computer system design of security and safety-critical multi-enclave systems to provide a framework for supporting the enforcement of diverse security multi-policies. The established wireless inter-enclave multi-policy paradigm manages multiple wireless security policies within heterogeneous systems. Applying the policy refinement rules presented in this work for a security enforcement procedure of an application system will reduce the proof effort for secure components.

The MILS architecture for high-assurance embedded systems

High-assurance systems require a level of rigor, in both design and analysis, not typical of conventional systems. This paper provides an overview of the Multiple Independent Levels of Security and Safety (MILS) approach to high-assurance system design for security and safety critical embedded systems. MILS enables the development of a system using manageable units, each of which can be analysed separately, avoiding costly analysis required of more conventional designs. MILS is particularly well suited to embedded systems that must provide guaranteed safety or security properties.