1 Introduction

Virtualization has been a hot topic in the enterprise space for quite some time, but has recently become an important technology for embedded systems as well. It is therefore important for embedded-systems developers to understand the power and limitations of virtualization in this space, in order to understand what technology is suitable for their products.

This white paper presents an introduction to virtualization technology in general, and specifically discusses its application to embedded systems.

We explain the inherent differences between the enterprise-systems style of virtualization and virtualization as it applies to embedded systems. We explain the benefits of virtualization, especially with regard to supporting embedded systems composed of subsystems with widely varying properties and requirements, and with regard to security and IP protection.

We then discuss the limitations of plain virtualization approaches, specifically as it applies to embedded systems. These relate to the highly-integrated nature of embedded systems, and the particular security and reliability requirements.

We present microkernels as a specific approach to virtualization, and explain why this approach is particularly suitable for embedded systems. We show how microkernels, especially Open Kernel’s OKL4 technology, overcome the limitations of plain virtualization. We then provide a glimpse at the future of this technology.