OS portal: an economic approach for making an embedded kernel extensible

Abstract

With the rapid development of embedded system techniques and Internet technologies, network-enabled embedded devices have grown in their popularity. One critical design trend of such devices is that they are shifting from static and fixed-function systems to more dynamic and extensible ones, which are capable of running various kinds of applications. To support the diversity of the applications, kernels on these devices must be extensible. However, making embedded kernels extensible is challenging due to the shortage of resources on these devices. In this paper, we propose the operating system portal framework, which makes embedded kernels become extensible while keeping the added overheads minimal. By storing kernel modules on a resource-rich server and loading them on demand, the need for equipping a local storage on the device is eliminated. In addition, we propose mechanisms for reducing the memory requirements and performing on-line module replacement on the embedded devices. According to the performance evaluation, our approach requires only 1% of the resource requirements, compared to the traditional approaches. This allows our framework to be applied on a wide range of embedded devices. (C) 2002 Elsevier Science Inc. All rights reserved.