Today virtualization technology is the focus of many new potential threats and introduces new security challenges that we must meet. The key problem is that malware can utilize the virtualization techniques of modern CPUs for "hidden virtualization" (invisible for user): to execute as a hypervisor and transform the working operation system (OS) into a "guest" state. In this work we analyzed and compared the functionality of several research virtual machine monitors (VMMs: BluePill, SubVirt, BitVisor) which can be used for hidden virtualization attack. A typical life circle of the hardware-accelerated VMM and mechanisms of hidden virtualization were also described. We also implemented the proof-of-concept prototype of research VMM and used it for tests with hidden virtualization of Linux operation systems. Our measurements demonstrated that malicious VMMs could efficiently hide their presence using hardware-accelerating technologies.A popularity of cloud services in which virtualization is widely used. According to Gartner, more than 80% of all server workloads will be virtualized by 2017. Cisco Global Cloud In dex shows similar "more than two-thirds». Virtualization tech nology security in has become a hot topic in the modem indus try. This can be explained by two factors: • There are a lot of security benefits to virtualization with mul tiple operation systems (OSs) working in parallel: easier business continuity and disaster recovery, single points of control over multiple systems, additional auditing and log ging capabilities for large infrastructures and etc. • Technologies of hardware-accelerated (HW-accelerated) virtualization allow to significantly increasing speed of the most difficult virtualization mechanisms (such as memory access, CPU sharing etc.). Although an abstraction of physi cal platform always degrades the overall system's perfor mance, the technologies of hardware-accelerated virtualiza tion can decrease the performance losses to imperceptible level. As the result, the fact of working in virtualized envi ronment can be totally unnoticeable for the end-user.Therefore, virtualization technology is the focus of many new potential threats and exploits while presenting new vulner abilities that must to be managed. The key problem is that mal ware can utilize the virtualization techniques of modern CPUs to execute as a hypervisor and transforming the working OS to the "guest" state. This process we call "hidden virtualization".As the result an attacker can gain a full low-level control over the system including access to RAM, disks, keyboard, network interfaces etc.The goal of this work is to investigate a possibility of running a hidden virtualization attack on a single-user computer system using existing technology of hardware-accelerated virtualiza tion (Intel VT-d). At the same time, we'd like to share our knowledge and experience in hardware-accelerated virtualiza tion. In contrast to the previous works (for example well-known
JPEG-LS, the well-known international standard for lossless and near-lossless image compression, was originally designed for non-scalable applications. In this paper we propose a scalable modification of JPEG-LS and compare it with the leading image and video coding standards JPEG2000 and H.264/SVC intra for low-complexity constraints of some wireless video applications including graphics.
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