Junghan Kim

A fault-tolerant gateway for in-vehicle networks

This paper presents a fault-tolerant gateway embedded system that uses two micro-controllers. One microcontroller performs the main function of achieving a gateway, often called by the main micro-controller. In contrast, another plays the role of checker for the main micro-controller, and is called the sub micro-controller. To achieve fault-tolerance, the checker monitors the state of the main micro-controller. In this paper, we propose hardware architecture for fault-tolerance and evaluate the performance of the proposed system.

A Reliable Gateway for In-vehicle Networks

Abstract This paper presents a reliable gateway for communication between the LIN, CAN, FlexRay protocols. A gateway is indispensable device for constructing in-vehicle networks. Networks with different protocols have to include an additional gateway in order to exchange information among different networks. The main function of the gateway is translation. However, there is some latency when a message is transferred from one node (source) to another (destination); further, there is a high probability of error due to different protocol specifications such as baudrates, message frame formats, and so on. Therefore the implementation of a reliable gateway is a challenging task. In this paper, we propose a reliable gateway based on OSEK OS and OSEK NM for in-vehicle networks. We develop a gateway embedded system and implement a reliable gateway mechanism. We then examine the developed gateway system and present the results of experiments with several trials.

A method for improving the reliability of the gateway system by using OSEK and duplication scheme

The gateway system is an essential component for network-to-network communication using different protocols inside a distributed system. Since reliability is an important aspect in an automotive system, here we propose a method for improving the reliability of the gateway system by using OSEK/VDX and duplication scheme. Three factors were considered for improving the reliability of the gateway. First, a high priority message must be processed first. Second, the gateway should not transmit messages to erroneous nodes that cannot receive messages by checking the accessibility of the destination node. Third, a sub-gateway should be used alternately with the main gateway when the main gateway cannot operate correctly. In this study, we developed a CAN and FlexRay gateway embedded system and applied the proposed method to this system.

MyAV: An all-round virtual machine monitor for mobile environments

Recently, various security issues in mobile devices have appeared due to improvement of the performance of mobile devices and the emergence of open mobile platforms. In this paper, we present MyAV, which is an all-round virtual machine monitor, to support various platforms from x86 desktops to ARM embedded platforms by minimizing the processor dependencies. It provides a secure execution environment using newly proposed technique of kernel-user address space separation. Many security vendors offer many different solutions including vaccine development for mobile devices, but it is still difficult to respond quickly to new malware. Another solution is resource isolation using virtual machine to share conventional hardware in a safe environment. However, existing virtual machines are unsuitable to be applied to mobile devices, because the original purpose of those virtual machines is based on server virtualization technology for operating a large number of guests. We present our design considerations using the resource isolation technique and report various experimental results based on the x86 desktop and an ARM embedded environment.

A method of task synchronization in a distributed system using FlexRay

In a distributed system, the synchronization of tasks executed in different nodes is necessary. Therefore, we propose a method of synchronization of tasks in a distributed system using FlexRay. FlexRay is expected to become a dominant protocol in automotive systems. It supports a clock synchronization mechanism. We present two methods for synchronization of tasks using a clock synchronized by FlexRay. One is a synchronization method for the start point of tasks. The other is a synchronization method for specific points in the task. We implement the proposed method as an experiment.

Software-based single-node multi-GPU systems for multiple display environments

In this paper, we suggest a novel multi-GPU scheme that can provide flexible interconnections between multi-GPUs and displays with no additional hardware by implementing new software features, while avoiding system overhead. Our proposed scheme offers the complete concept of windowing system and GPU driver for single-node multi-GPU system on multiple display environments.

Software-based single-node multi-GPU systems for interactive display wall

A display wall, one of the multiple display environments (MDEs), has been widely adopted in various fields including consumer electronics. Conventional display walls are constructed by utilizing cluster-based systems where multiple displays are connected via multiple cluster nodes. However, cluster-based systems have suffered from communication overheads among the cluster nodes when they provide interaction features and run diverse applications. This paper proposes a software-based single-node multi-GPU system for interactive display walls. The proposed system allows multiple GPUs in a single-node system to connect multiple displays, by providing an individual compositor for each GPU in the system. This paper also analyzes memory management models of multi-GPU systems and compositing overheads for multiple displays. Experimental results show that the FPS (frames per second) of the proposed system outperforms that of the conventional system by up to 1.36x, reducing copy overheads among the GPUs by efficient memory management and distributing compositing overheads to multiple GPUs.

Address Space Maintaining Scheme for Fast Program Execution in Linux-based Systems

The environment of Internet of Things (IoT) wherein various devices are connected through the Internet with value-added network functions, is currently a subject of active study. Accordingly, the existing computing environment based on desktop or mobile systems is being expanded into a computing environment of more diverse devices. Because the response of program launching is important in terms of User Experience (UX) in IoT environments, the technology for guaranteeing rapid response of program launching in IoT devices is getting the focus of much current research. In this paper we analyze the Zygote technique, which is being used for faster program execution in Android systems, and, based on our results, we propose an address space maintaining scheme for the rapid launching of programs for use in Linux-based systems. Our scheme utilizes the Copy on Write (CoW) technique in Linux systems as well as the Zygote technique of Android systems. In order to evaluate the proposed scheme, we implemented our scheme on Linux systems and performed several experiments. The experimental results show that the proposed scheme shortens the launching time up to 99%, compared to the existing technique.

Vehicular management system

This paper presents a vehicular management system (VMS) that consists of gateway, hand-set and vehicular management program (VMP). With the increased demand for vehicular services, overall electronic system has been developing rapidly in the last two decades. As the number of electronic devices has increased, automatic control and management have been made possible. Especially, automatic management of a vehicle will provide great benefits to owner (driver) because of increase in convenience. In this paper, we construct a simple VMS which can apply to a practical automotive system.

Simulation for the distributed system with consideration of hardware characteristics

Developing and validating a distributed system requires great cost, time, and effort than a centralized system because the systems are inherently concurrent, asynchronous, and nondeterministic. For this reason, accurate simulation function is significantly important for developing the distributed system. In particular, it finds applications in the automobile embedded system industry, which requires short time-to-market. If the simulation function is able to simulate the hardware characteristics of the distributed system, the accuracy of the simulator increases. We develop a 16-bit embedded system for an electronic control unit (ECU) in an automobile system and a block for modeling and simulating for distributed system with considering of hardware characteristics, especially caused by network characteristics. In this paper, consequence of simulation with real-value in the 16-bit embedded system is compared.