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In the ARM-based mobile virtualized environment, optimizing both the network throughput and the latency for network-intensive applications is of great importance. Our experimental studies have shown that the context switch between the host and guest triggered by a hypercall results in CPU overload and thus degrades the I/O performance under an intensive workload. To address this problem, we propose the Adaptive Hypercall Coalescing (HyperCo) algorithm, a software-only approach to optimizing the network I/O performance by reducing the number of hypercalls and achieving a trade-off between throughput and latency. We implement HyperCo by modifying the front-end driver of Virtio-net on the KVM/ARM platform, and we carry out extensive performance evaluations, which indicate that the number of hypercalls and the load on the CPU can be significantly reduced. We show that HyperCo can significantly improve the network throughput under an intensive workload while keeping a low penalty by adapting a coalescing interval dynamically at a low frequency of network I/O requests. [ABSTRACT FROM AUTHOR]

This study examines employees’ intention to comply with organizational BYOD security policies (ISSP). We derived our research model from reactance, protection motivation and organizational justice theories. Our results demonstrate that employees perceived response efficacy and justice positively affect intention to comply with BYOD ISSP. Perceived freedom threat negatively affects compliance intention. Employees’ perceived cost associated with compliance behavior increases perceptions of freedom threat. Security awareness programs have a dual effect: an increase in employee’s response efficacy (positive) and response cost (negative). The availability of an IT support team for BYOD increases employees’ response-efficacy and perceived justice. [ABSTRACT FROM AUTHOR]

Mobile virtualization introduces extra layers in software stacks, which leads to performance degradation. Notably, each I/O operation has to pass through several software layers to reach the NAND-flash-based storage systems. This article targets at optimizing I/O for mobile virtualization, since I/O becomes one of major performance bottlenecks that seriously affects the performance of mobile devices. Among all the I/O operations, a large percentage is to update metadata. Frequently updated metadata not only degrade overall I/O performance but also severely reduce flash memory lifetime. In this article, we propose a novel I/O optimization technique to identify the metadata of a guest file system that is stored in a virtual machine image file and frequently updated. Then, these metadata are stored in a small additional non-volatile memory (NVM), which is faster and more endurable to greatly improve flash memory's performance and lifetime. To the best of our knowledge, this is the first work to identify the file system metadata from regular data in a guest OS image file with NVM optimization. The proposed scheme is evaluated on a real hardware embedded platform. The experimental results show that the proposed techniques can improve write performance to 45.21% in mobile devices with virtualization. [ABSTRACT FROM AUTHOR]

Recent growth in the processing and memory resources of mobile devices has fueled research within the field of mobile virtualization. Mobile virtualization enables multiple persona on a single mobile device by hosting heterogeneous operating systems (OSs) concurrently. However, adding a virtualization layer to resourceconstrained mobile devices with real-time requirements can lead to intolerable performance overheads. Hardware virtualization extensions that support efficient virtualization have been incorporated in recent mobile processors. Prior to hardware virtualization extensions, virtualization techniques that are enabled by performance prohibitive and resource consuming software were adopted formobile devices. Moreover,mobile virtualization solutions lack standard procedures for device component sharing and interfacing between multiple OSSs. The objective of this article is to survey software- and hardware-based mobile virtualization techniques in light of the recent advancements fueled by the hardware support for mobile virtualization. Challenges and issues faced in virtualization of CPU, memory, I/O, interrupt, and network interfaces are highlighted. Moreover, various performance parameters are presented in a detailed comparative analysis to quantify the efficiency of mobile virtualization techniques and solutions. [ABSTRACT FROM AUTHOR]

The virtualization techniques are receiving more attention lately in mobile device security. In this study, we present SecureDom which is the device security of data-centric that aims to protect private, enterprise or sensitive data from various attacks and threats. To achieve it, we provide the mobile device security platform based on domain separation and suggests three essential secure functions which should be offered for secure domain: authentication/access control (AAC) module, secure storage (STR) module and encryption/key management (EKM) module. In secure functions, the AAC module applies two-factor authentication by user and app to access SD, the STR module introduces the enhanced abilities of secure filesystem and EKM module is in charge of security algorithms for data encryption, integrity validation or key generation. Here, EKM module can utilize the existing encryption module that is certified by cryptographic validation program. In the experiment, it demonstrates that some notable overheads are caused in the performance of virtualization engine and inter-domain communication (IDC) performance based on hypervisor, while it provides the strong isolation in domain, IDC, filesystem and resource and the separation of processes. [ABSTRACT FROM AUTHOR]

Virtualization offers significant benefits, such as better isolation and security for mobile systems. However, the limited amount of memory and virtualization’s memory-demanding nature make it challenging to virtualize mobile systems efficiently. In this paper, we utilize morphable resistive memories to design a high-performance mobile system with an extensible memory space. With morphable resistive memories, a simple and effective page management technique, Balloonfish, is proposed to convert the memory cell state between multilevel and single-level for achieving a balance between performance and memory space. First, an application-specific page allocation is proposed for managing morphable resistive memories in virtualized mobile systems. Besides, we use a balloon-style algorithm to balance memory allocation among multiple virtual machines. Our evaluation based on the Samsung Exynos 5250 system-on-chip with various real Android applications shows that our system achieves 28.63% performance improvement compared with the baseline scheme. [ABSTRACT FROM AUTHOR]

This article considers an embedded virtualization platform design for an important practical scenario in the business world: Bring Your Own Device (BYOD), which requires isolating the company's privileged information access from employees' entertainment environment. For this purpose, the authors propose an alternative architecture design called vNative for complete isolation among different usage scenarios. vNative makes one virtual machine, called the foreground VM (FVM), monopolize all resources at any time for use; the other VMs, called the background VMs (BVMs), are kept reactive with an expeditious context-switching scheme between FVM and BVM. vNative is suitable and reliable for BYOD to freeze other unauthentic applications, and it is consistent with the power consumption and limited display size of mobile smart devices. vNative achieves 98.6 percent of native performance with 6.5 percent power overhead, and its VM switching responsiveness is within 376 ms. [ABSTRACT FROM PUBLISHER]