Virtual Network Computing Research Articles

Proposal of a Novel Setup for Linac Monitoring Using a Specifically Designed Plastic Scintillator and a Spectrophotometer

In this work we report the design, implementation and results of an alternative monitoring system for a linear accelerator (LINAC) used in medical therapy. The system proposed consist in aslab of scintillator plastic with awavelength shifter fiberoptically coupled to collect the light generated,and a Spectrophotometer Ocean Optics USB4000 as analyzer. The control was made with two computers, one into the therapy room and another, using a VNC (Virtual Network Computer) and Ethernet wire, outside of the room in order to avoid radiation exposure. The LINAC dose range covered was 1, 2, 3, 4, 5, 10, 20, 30 and 40 Monitor Units (MU) with 6 and 18 MeV energy photons. The spectrum obtained was compared with the measures of the LINAC ionization camera used to calibrate it. The results obtained allowus to propose this device as an alternative method to monitor the LINAC performance.

Remote Display Access Using Remote Frame Buffer and IO Streaming

This paper propose a virtual network computing (VNC) based architecture for accessing the desktops of remote computers from a cellular phone. A viewer is provided on the cellular phone that enables the user to see and manipulate the desktop of various remote systems such as MS Windows, Macintosh, and UNIX. The system to be accessed must be running a VNC server and it must be attached to a network. A proxy is used to send the image of the desktop to the cellular phone, to convert different devices, to suppress network traffics, and to support recovery from an unscheduled disconnection. To reduce user effort and solve problems inherent to the cellular phone‟s small screen, several functions are provided on the cellular viewer. Frequently used screen areas can be assigned and restored quickly by using the Shortcut function. The Guidance function can be used to show the current key assignments. Two areas can be viewed at the same time by the Twin view function. In this paper a prototype of the proposed architecture has been implemented using Java and has been tested on a Java-enabled cellular phone emulator.

Implementing Cloud Based Virtual Computer Network Labs for Online Education: Experiences from a Phased Approach

On-line instruction rather easily accommodates courses in some fields such as history, sociology, business administration and political sciences. However, it poses significant challenges for courses in technical fields that require hands-on experimentation. Courses in computer networking area constitute such an example. Given the demand for on-line courses and the trend for migration to online mode, there is a need to devise strategies that would allow students to conduct computing experiments remotely. Virtualization is a rapidly evolving technology that provides opportunities for online computer education. Through virtualization tools, it is possible to convert brick-and-mortar labs into virtual network labs. Using online virtual network lab tools, students may build, troubleshoot and test networks using their personal computers and, thereby, eliminate the commute to the labs. Cloud technology, another rapidly growing field, can help an organization achieve significant savings in IT services and infrastructure costs, as well as enhance IT support for organizational operations. Confluence of cloud and virtualization technologies present new opportunities for online education. However, there are significant issues to surmount in order to apply these technologies to computing-related courses and in particular to online computer networking courses. This paper presents experiences gained from transforming a traditional computer lab into an online virtual domain at the authors' university. The network lab described in this paper is utilized mostly for graduate computer networking, network security and wireless networking courses. The phased approach depicted in this paper should help academic institutions gain insights into technical and operational challenges in building and operating an online virtual lab.

The Use of Remote Access Tools by System Administrators Today and their Effectiveness: Case Study of Remote Desktop, Virtual Network Computing and Secure Android App

This study sought to find out how Network Administrators make use of remote access tools in their daily activities as Network Administrators. It also investigated how effective and reliable these tools have been to Network Administrators in terms of the tools’ ability to return desired results to the users (Network Administrators). From the findings of this research, 37.93% of the Network Administrators use remote access tools to do file transfer from one computer to the other, 26.44% use remote access tools to share or deploy applications on their local networks, 20.69% use remote access tools to access their terminal servers and 14.94% use remote access tools to create and set user privileges on their networks. The investigation further revealed that 36.78% of Network Administrators agreed that remote desktop was effective, 24.14% also agreed that the secure android app was effective and 21.84% agreed that VNC was also effective. General Terms Remote Access Tools, Protocols, effectiveness, reliability.

CONTROLLING AND MONITORING OF REMOTE HOST

In today’s world, the role of remote access is changing dramatically. So accessing network remotely is an important issue. The proposed system allows administrator to access network from anywhere at any time. Administrator user can control and monitor the network using RFB (Remote FreameBuffer) protocol. Administrator User can run server side commands using android mobile phones. Administrator User can access desktop within the Wi-Fi- rang. Virtual Network Computing(VNC) is, in essence, a remote display system which allow to you to view a computing ‘desktop’ environment not only on machine where it is running, but also from anywhere on the network. The system can extend the limit rang of accessing organization.

Performance Analysis of Virtual Computer Network Based on Cisco Cloud Services Router 1000V in a Private Cloud Environment

Abstract Virtualization of physical network devices is a relatively new technology, that allows to improve the network organization and gives new possibilities for Software Defined Networking (SDN). Network virtualization is also commonly used for testing and debugging environments, before implementing new designs in production networks. Important aspect of network virtualization is selecting virtual platform and technology, that offer maximal performance with minimal physical resource utilization. This article presents a comparative analysis of performance of the virtual network created by the virtual CSR1000v and virtual machines running Windows 8.1 on two different virtual private cloud platforms: VMware vSphere 5.5 and Microsoft Hyper-V Server 2012 R2. In such prepared testbed we study the response time (delay) and throughput of virtual network devices.

Improving the virtualization of rich applications by combining VNC and streaming protocols at the hypervisor layer

SummaryVirtual desktop infrastructure (VDI) solutions seek to provide a satisfactory user experience at the client side when accessing remote desktop applications, even from mobile devices with limited capabilities. This paper presents a new approach, improving on previous work by the authors, in which a combination of Virtual Network Computing (VNC) and streaming protocols allowed efficient remote web access to virtualized applications within a cloud architecture. The new approach simplifies virtual machine templates, from which virtual machine instances are deployed, by centralizing software modules, greatly simplifying their management. Our new contribution consists of an integrated solution with specific WebM video encoding modules in charge of application visual output processing, an Hypertext Transfer Protocol (HTTP) streaming server, and a VNC server. The solution can be installed in the hypervisor of the host machines instead of replicating the servers and modules throughout the guest (virtual) machines that run the virtualized applications. Consequently, their implementations are unique and independent of the operating system of the virtual machines. In short, it is not necessary to provide different implementations for different operating systems, which reduces the complexity of virtual machine templates and greatly simplies platform management. To demonstrate our solution, we have modified the Quick Emulator (QEMU)‐Kernel‐based Virtual Machine (KVM) hypervisor source code accordingly. We also present qualitative and quantitative analyses that demonstrate that the new approach is advantageous in terms of software management and quality of experience, compared with our previous work and other well‐known thin clients, contributing to the enhancement of VDI systems. Copyright © 2015 John Wiley & Sons, Ltd.

Approach to access the Remote device in same network using Virtual Network Computing: An Accessibility Endeavor

Approach to access the Remote device in same network using Virtual Network Computing: An Accessibility Endeavor

Exploration for Soft Handoff Decorations in CDMA Systems

In CDMA communication systems with respect to CDMA the relative area cannot be increased and always the possession call onset rate is stipulated; it’s denoted and stated that mounting, and all transferring soft handoff area space is guaranteed to extend the cell reporting detachment. CDMA with same frequency is always possible to make a new connection before parting with modern cell is called as “make-before break” or “soft” handoff. For reducing less intervention and purpose of increasing capability soft handoff needs to reduce the power. The proposed scheme of winnable handoff calculating with original mobility, this set up was used in Channel Changeable Set (CCS). When channels are converted and processed with CCS based on the new handoff request made. Performance of CDMA is well and scarification of the quality service is also done well. In this paper signal transmission and soft handoff are also discussed. New handoff scheme is also done with great mechanism incorporates, and the transmission is done with good frequency. Signal to Interference plus Noise Ratio (SINR) for wireless networks is used in many ways especially in power control mechanism. SINR is doing major role in power control systems in the interference of noise ratio form. Diversity exploits with random nature and back propagation also used in Virtual Network Computing (VNC) based architecture. All Call Admission Control (CAC) is also measured which estimates the power function. Always we need to compare with CAC with completed power control functions. CDMA system has introduced the signal propagation performed and overcast the system. Variable speech allows both voices with mutable time temptation that is cut off when signal transmission is also travelled with proper propagation.

English

Mobility is an important attribute in todays computing world. Mobile devices,smartphone and tablet PC are becoming an integral part of human life because they are most effective and convenient communication tools. This paper proposes a system to connect and access the desktops of remote computer systems using an android based Smartphone. Virtual Network Computing based architecture is used to develop the proposed system. Through a VirtuMob viewer provided on the users Smartphone, the user will be able to access and manipulate the desktops of remote computers. Several functionality such as viewing the desktop, mouse operations, keyboard operations, manipulation of documents can be performed from the Smartphone. VirtuMob server should be running on the remote system and it must be attached to a network. VirtuMob Accelerator is used to process the RFB frames of the desktop, perform Encoding of the frames and then relay the frames to the viewer over the internet. Several Encoding techniques are studied and analysed to determine which is best suited for the proposed system.

Early-phase performance exploration of embedded systems with ABSOLUT framework

Future interactive embedded systems will support a large number of applications providing users with services related to e.g. telecommunication, audio and video, digital television, internet and navigation. To accommodate these performance demanding applications, the digital processing architectures will evolve from current system-on-chips to massively parallel computers consisting of heterogeneous subsystems connected by a network-on-chip. More flexibility, scalability and modularity are needed from the embedded devices. Consequently, the complexity of system design will increase by orders of magnitude. New methods and tools are needed for the performance evaluation of future embedded systems due to the increasing system complexity. This paper presents a high-level performance modelling and simulation approach called ABSOLUT that alleviates exploration complexity by using abstract virtual system models. The characteristics of the applications are abstracted to workload models that at the bottom level consist of instruction-like primitives. The workload models can be created from application specifications, measurement results, execution traces or source code. The complexity of the execution platform models is reduced since the processing elements need not be modelled in detail and data transfers and storage are simulated only from the performance point of view. The approach enables early evaluation, since the modelling and simulation of complete systems does not require mature hardware or software to exist. ABSOLUT has been applied to a number of case studies including mobile phone usage, MP3 playback, MPEG4 encoding and decoding, 3D gaming, virtual network computing and parallel software defined radio applications. The platforms modelled are either existing or future designs for both embedded systems and personal computers. In several cases, the results obtained from simulations are compared to measurements from real platforms, which reveal an average difference of 12% in the results. This exceeds the accuracy requirements expected from virtual system based simulation approaches intended for early evaluation. In this paper, the most recent enhancements of the ABSOLUT methodology and tool framework are applied in a FFMPEG case study on OMAP4 platform model. The simulation results are compared with those obtained from the execution on an OMAP4-based PandaBoard.

Security Enhancement of Out-of-band Remote Management in IaaS Clouds

In Infrastructure-as-a-Service (IaaS) clouds, the users manage the systems in the provided virtual machines (VMs) called user VMs through remote management software such as Virtual Network Computing (VNC). For dependability, they often perform out-of-band remote management via the management VM. Even in the case of system failures inside their VMs, the users could directly access their systems. However, the management VM is not always trustworthy in IaaS. Once outside or inside attackers intrude into the management VM, they could easily eavesdrop on all the inputs and outputs in remote management. To solve this security issue, this paper proposes FBCrypt for preventing information leakage via the management VM in out-of-band remote management. FBCrypt encrypts the inputs and outputs between a VNC client and a user VM using the virtual machine monitor (VMM). Sensitive information is protected against the management VM between them. The VMM intercepts the reads of virtual devices by a user VM and decrypts the inputs, whereas it intercepts the updates of a framebuffer by a user VM and encrypts the pixel data. We have implemented FBCrypt for para-virtualized and fully-virtualized guest operating systems in Xen and TightVNC. Then we confirmed that any keystrokes or pixel data did not leak.

Interactive multicentre teleconferences using open source software in a team of thoracic surgeons

Real-time consultation between a team of thoracic surgeons is important for the management of difficult cases. We established a system for interactive teleconsultation between multiple sites, based on open-source software. The graphical desktop-sharing system VNC (virtual network computing) was used for remotely controlling another computer. An image-processing package (OsiriX) was installed on the server to share the medical images. We set up a voice communication system using Voice Chatter, a free, cross-platform voice communication application. Four hospitals participated in the trials. One was connected by gigabit ethernet, one by WiMAX and one by ADSL. Surgeons at three of the sites found that it was comfortable to view images and consult with each other using the teleconferencing system. However, it was not comfortable using the client that connected via WiMAX, because of dropped frames. Apart from the WiMAX connection, the VNC-based screen-sharing system transferred the clinical images efficiently and in real time. We found the screen-sharing software VNC to be a good application for medical image interpretation, especially for a team of thoracic surgeons using multislice CT scans.

Implementation and evaluation of fast mobile vnc systems

VNC (virtual network computing) is a popular tool for sharing an application, allowing users to access graphic displays remotely. In mobile VNC systems, it has been challenging to increase screen update rate by fast screen image encoding. In this paper, we implement a prototype system for mobile VNC, and several works are done for improving screen update rate. At first, a number of video encoders are integrated into a prototype system, and we investigate what is the most suitable codec for mobile VNC. The existing RFB protocol is extended straightforwardly to integrate video codecs. Next, the overall system architecture is modified from serial operation to parallel. Finally, we propose a modified region coding to further reduce the encoding time of screen images. The proposed methods are implemented into our prototype mobile VNC system, and practical performances are widely evaluated. We report that JPEG is the most suitable for mobile VNC in terms of both complexity and compression ratio. In addition, the proposed modified region coding can decrease encoding time, and consequently increase screen update rate.

Remote Internet Access to Advanced Analytical Facilities: A New Approach with Web-Based Services

Over the past decade, the increasing availability of the World Wide Web has held out the possibility that the efficiency of scientific measurements could be enhanced in cases where experiments were being conducted at distant facilities. Examples of early successes have included X-ray diffraction (XRD) experimental measurements of protein crystal structures at synchrotrons and access to scanning electron microscopy (SEM) and NMR facilities by users from institutions that do not possess such advanced capabilities. Experimental control, visual contact, and receipt of results has used some form of X forwarding and/or VNC (virtual network computing) software that transfers the screen image of a server at the experimental site to that of the users' home site. A more recent development is a web services platform called Science Studio that provides teams of scientists with secure links to experiments at one or more advanced research facilities. The software provides a widely distributed team with a set of controls and screens to operate, observe, and record essential parts of the experiment. As well, Science Studio provides high speed network access to computing resources to process the large data sets that are often involved in complex experiments. The simple web browser and the rapid transfer of experimental data to a processing site allow efficient use of the facility and assist decision making during the acquisition of the experimental results. The software provides users with a comprehensive overview and record of all parts of the experimental process. A prototype network is described involving X-ray beamlines at two different synchrotrons and an SEM facility. An online parallel processing facility has been developed that analyzes the data in near-real time using stream processing. Science Studio and can be expanded to include many other analytical applications, providing teams of users with rapid access to processed results along with the means for detailed discussion of their significance.

Virtual Network Computing Based Droid desktop

Our project is an Android application based on Virtual Network Computing” which helps people to access their laptops, personal computers using smartphones over a wireless network. Features like wireless data transfer between the android device and the client are also supported. The Integrated development environment used was Eclipse with the android plugin, and the server side (your laptop,pc etc.) programming was done using java. Client -server architecture was established for two way communication purpose where client was the android Smartphone and server was the windows desktop which communicate over TCP layer. The android client takes inputs from the users and sends the protocols for the execution of the mouse, keyboard and zooming events. The server parses such protocols and executes them using robot class of java. The desktop in turn takes screenshots continuously using robot class and sends them to the smartphone, thus establishing a two way communication network. The server sends the user interface to the client using the remote frame buffer. Remote frame buffer is the protocol used in virtual network computing. At the same time server receives commands from the client in the form of protocols. Since both the processes need to be performed simultaneously two threads are created, one to receive protocols from the client and the other to send user interface to the client. In the similar way the client receives the screenshots in the child thread and sends the protocols in the main activity thread which gives the client a realistic environment of the Desktop. Threads need not be synchronized. We created a simple Desktop server captures the screenshots of the machine it is running on and sends the images continually through an outputstream to the client in a particular string format. The server sends 30 screenshots per second to the client for the latter to obtain a live feed of the Desktop. The server waits for the input data stream from the client. In order to completely access a desktop we need to access its hardware. However, the hardware cannot be directly accessed. So the android generates a standard protocol for each user interaction with the smartphones and sends it to the server. The touch events are considered analogous to mouse events and an onscreen keyboard of android replaces the standard IBM PC keyboard. Whenever data stream is sent by the client in the form of a string the server parses that string in accordance to our protocols and executes using robot class of java. Some features like zooming and panning are also provided.

Multi-Platform Mobile Thin Client Architecture in Cloud Environment

In a thin client computing architecture, application processing is delegated to a remote server rather than running the application locally. User input is forwarded to the server, and the rendered images are relayed through a dedicated remote display protocol to the user's device. Thin-client computing offers the promise of easier-to-maintain computational services with reduced total cost of ownership. With the increasingly development of cloud technology, the server side of thin client architecture is able to be deployed in cloud, thus makes the full use of the features of the Cloud, for example, virtualization, flexibility, security, and dynamic management. Meanwhile the client side can also use the mobile thin device. The traditional thin client architecture, which is platform-dependant, however, limits the most benefit of the software providers and end-users. So we propose multi-platform thin client architecture, which use VNC (Virtual Network Computing) protocol and run in the cloud environment. In this architecture, both side of the service will benefit a lot. In the one hand, the end-user can use cheap, light mobile terminal which enjoy all kind of software service of different platform. In the other hand, the software provider or developer can get more benefit with more download mass and wider circulated.

NVLab, a Networking Virtual Web-Based Laboratory that Implements Virtualization and Virtual Network Computing Technologies

In various ICT courses, it is necessary to establish a proper space where each learner has access to a set of network devices with which he/she can build and test networks with different structures and components. This will enable the learners to practice working on multiple devices as in the case of real world context, and freely apply modifications to the network structure to solve any issue that may arise with the current scenario. While on-campus facilities are designed to meet this criterion, current Web-based laboratories either have fixed network designs, or do not offer a number of real devices to work on. Taking a step forward toward building a Web-based laboratory, we used open source Virtualization and Virtual Network Computing technologies in NVLab, a system that offers the learners tools to draw, configure, test, and troubleshoot network designs using real Operating System instances running in the virtual mode on a host machine. The functionality of the system has been experimented by introducing a case study exercise to a group of remote learners as part of Computer Networks course. Evaluating the participants' advancement was done by comparing their answers to a level test prior and after completing the exercise. The evaluation showed that the learners achieved better results in the level test after completing the exercise and were able to use the system efficiently.

Simulation Platform: Model simulation on the cloud

Simulation Platform: Model simulation on the cloud

INCF Japan-Node and Platforms

Event Abstract Back to Event INCF Japan-Node and Platforms Usui Shiro1* 1 Neuroinformatics Japan Center, RIKEN BSI, Japan The INCF national node of Japan (J-Node) (http://www.neuroinf.jp/) is established at the Neuroinformatics Japan Center (NIJC), RIKEN Brain Science Institute (BSI). Based on the achievement of a Japanese pilot study on Neuroinformatics Research in Vision (1), we developed a base-platform XooNIps (http://xoonips.sourceforge.jp) and several neuroinformatics platforms (PFs). PF committee members collaborate to develop databases that are available for use online, and together with the J-Node committee, we promote domestic activities in neuroinformatics in Japan. PFs currently running under the J-Node are as follows: Visiome, Brain Machine Interface, Invertebrate Brain, Cerebellar Development Transcriptome, Comprehensive Brain Science Network, Cerebellar, Neuro-Imaging, Dynamic Brain, BSI-NI (under development) and Simulation (under development) (2). We here describe 2 platforms which are under development. The rest of PFs are opened at the J-Node portal. BSI-NI platform is a general term for several platforms which developed in BSI. RIKEN has been participating in the "Integrated Database Project" which MEXT launched from 2006 to develop and promote life science databases in Japan. To meet the same needs in the brain science, BSI established BSI-NI committee to promote neuroinformatics in April 2008. The following databases are under development to open. •BSI Microarray Database •Construction of 3-Dimensional brain atlas of novel experimental rodent "Degu" •Construction of 3-Dimensional brain atlas of novel experimental primate "Common Marmoset" •Multichannel EEG data for Brain Machine Interface (BMI) and/or Human Emotions (HE) Simulation platform (SimPF) provides a common environment for testing, evaluating and sharing computational models via web browser. Users can run a trial of computational models that are registered on PFs and Neuroinformatics databases; no need to install any software on their computers. A user is asked to upload a script of a model to SimPF from a web browser. Once uploaded, SimPF assigns a virtual machine (VM) for the user from SimPF clouds, and connects the VM automatically to the user's browser via VNC (Virtual Network Computing) protocol. We are also providing MPI simulation environment for various kind of neuron and local-circuit simulation. The system consists of portal hosts, ganglia server and execution hosts. Linux and open source software are used for every host and server. Anyone can easily access and use our cloud simulation environment from browser. Install and configuration methods are provided by the PF. Since the establishment of J-Node and PFs 5 years ago, top-page access statistics of unique users per day for each PF are shown in the Figure. The slopes at the initial phase are about 20 persons/day, which is mostly by the committee members to develop the PF. Once the URL is publicized at large, the slope becomes roughly 100 persons/day, rising by 5 times. This shows the importance of such PFs in neuroscience.