Linux Devices Research Articles

Platform Independent Embedded Linux OTA Method

Embedded devices are often used at remote locations. Accordingly, since it is difficult and costly to physically access the devices for firmware updates, the updates are made with Over-the-Air (OTA). OTA is a firmware update method that allows embedded devices to be updated wirelessly without requiring physical access. OTA applications for Embedded Linux devices are platform-dependent. Therefore, the aim of this study is to develop an easy integrated, steady, and robust OTA method. This method runs in the background without any user action on a platform-independent Embedded Linux device and it has a small footprint. The firmware is compressed in this method. The compressed firmware is uploaded to a storage area such as a remote drive, cloud, and repository. The storage area is used efficiently thanks to compressed firmware. The OTA application checks versions of firmware in the storage area and compares them with firmware running on the device. It decides which version is more up-to-date. If the version of the firmware in the storage area is more up-to-date, the OTA application runs in the background and downloads the updated firmware without interfering with the working functions on the device. After the download is completed, compressed firmware is extracted and flashed into the specified memory location. When the device is rebooted after the procedure is completed, the device is going to boot with the new version of the firmware. Consequently, the OTA application can be integrated easily on most Embedded Linux platforms. Besides the OTA application can be enhanced with security and power-safe features.

Virtual Colour Atlas

AbstractA web application (Virtual Colour Atlas) has been developed that implements seven of the leading color order systems: Colorcurve, Coloroid, DIN 6164, Munsell, OSA‐UCS, NCS, and Swiss Colour Atlas 2541, three color spaces: CIE xyY, CIELAB, and CIELUV, and three colour ranges: BS:5252, RAL 840‐HR, and RAL 841‐GL—allowing the user to view any of the core planes in the color space of each of these systems. The Virtual Colour Atlas is freely available at (www.vcsconsulting.uk) and provides visual interaction with these systems using any modern browser hosted on a device with a sufficiently large physical display including: windows PCs, Macs, iPads, Linux devices, and smart televisions (HD to 8 K). This paper provides a brief background on the systems, describes the Virtual Colour Atlas software and history, and discusses example applications of the Virtual Colour Atlas.

Distributed Virtual Time-Based Synchronization for Simulation of Cyber-Physical Systems

Our world today increasingly relies on the orchestration of digital and physical systems to ensure the successful operations of many complex and critical infrastructures. Simulation-based testbeds are useful tools for engineering those cyber-physical systems and evaluating their efficiency, security, and resilience. In this article, we present a cyber-physical system testing platform combining distributed physical computing and networking hardware and simulation models. A core component is the distributed virtual time system that enables the efficient synchronization of virtual clocks among distributed embedded Linux devices. Virtual clocks also enable high-fidelity experimentation by interrupting real and emulated cyber-physical applications to inject offline simulation data. We design and implement two modes of the distributed virtual time: periodic mode for scheduling repetitive events like sensor device measurements, and dynamic mode for on-demand interrupt-based synchronization. We also analyze the performance of both approaches to synchronization including overhead, accuracy, and error introduced from each approach. By interconnecting the embedded devices’ general purpose IO pins, they can coordinate and synchronize with low overhead, under 50 microseconds for eight processes across four embedded Linux devices. Finally, we demonstrate the usability of our testbed and the differences between both approaches in a power grid control application.

TinCan: User-Defined P2P Virtual Network Overlays for Ad-hoc Collaboration

Virtual private networking (VPN) has become an increasingly important component of a collaboration environment because it ensures private, authenticated communication among participants, using existing collaboration tools, where users are distributed across multiple institutions and can be mobile. The majority of current VPN solutions are based on a centralized VPN model, where all IP traffic is tunneled through a VPN gateway. Nonetheless, there are several use case scenarios that require a model where end-to-end VPN links are tunneled upon existing Internet infrastructure in a peer-to-peer (P2P) fashion, removing the bottleneck of a centralized VPN gateway. We propose a novel virtual network — TinCan — based on peerto-peer private network tunnels. It reuses existing standards and implementations of services for discovery notification (XMPP), reflection (STUN) and relaying (TURN), facilitating configuration. In this approach, trust relationships maintained by centralized (or federated) services are automatically mapped to TinCan links. In one use scenario, TinCan allows unstructured P2P overlays connecting trusted end-user devices — while only requiring VPN software on user devices and leveraging online social network (OSN) infrastructure already widely deployed. This paper describes the architecture and design of TinCan and presents an experimental evaluation of a prototype supporting Windows, Linux, and Android mobile devices. Results quantify the overhead introduced by the network virtualization layer, and the resource requirements imposed on services needed to bootstrap TinCan links.

A java API interface for the integration of DTV services in embedded multimedia devices

Most of the modern DTV sets and set top boxes are embedded Linux devices. Apart from playing broadcast transport streams, some of these devices offer network connectivity and various applications. The development of software for these devices is not unified, so there is no compatibility between applications developed by different vendors. On the other hand, there are embedded systems developed on top of the embedded Linux kernel which offer network connectivity and a large number of applications that are available for download. Most of the applications developed for these platforms are developed in the Java programming language. However, those platforms do not support DTV services. This paper presents a proposal for the integration of DTV services into embedded systems which support the Java programming language. The proposed solution offers complete DTV functionality, along with the operation of regular applications. The proposal includes two API specifications: the Java API that is used to access DTV content from Java applications, and the DTV Middleware API that is used to connect the native code to the Java API.