Parallel - A Zero-Client Computing Application

Size: px

Start display at page:

Download "Parallel - A Zero-Client Computing Application"

Howard Shaw
6 years ago
Views:

1 Parallel - A Zero-Client Computing Application STANCU MIHAI, DANA SIMIAN Lucian Blaga University of Sibiu Faculty of Sciences 10, Victoriei Bd., Sibiu, Romania stancu.mihai.dorian@gmail.ro dana.simian@ulbsibiu.ro Abstract: The purpose of this paper is to explore the concepts of zero-client computing and to introduce and present Parallel, a software solution proposed and designed by us, that allows rapid deployment of such architectures. Parallel enables multiple users to do their work simultaneously on the same computer, using only separate monitors, keyboards and mouses, effectively providing the same experience as a dedicated PC for each user. Topics include a zero-client definition, benefits, software impact, deployment process, management and comparisons with existing solutions. Key-Words: zero-client, centralized computing, green computing 1 Introduction This paper introduces and presents Parallel, a software solution, designed by us, which allows a single computer to be used simultaneously by multiple users, each having a separate monitor, keyboard and mouse. The purpose is to do a succinct, general presentation of the application and its importance. Technical details regarding the implementation will constitute the subject of a future, extended article. We begin with a short review of the main disadvantages of computer system architectures that assume a dedicated PC to be available at every user interaction point. In [1] we are provided with a brief overview of the current state of computing, as today most office, commercial or industrial applications are deployed on dedicated PCs or workstations. The PC is then connected to a network and a variety of peripheral devices. This type of architecture is found everywhere from universities, libraries, retail, financial, airline, food service, to manufacturing and most other commercial markets. In [8] the main disadvantages of this type of architecture are emphasized, ranging from initial costs: equipment, installation, configuration, designing infrastructure, training and administration, security and backup; to ongoing costs: repairs, replacements and upgrades (either hardware or software), user incidents, maintenance and support. In [1] a different disadvantage is mentioned: hardware generally has moving parts, for example hard drives, CD/DVD drives, coolers, etc. that have expected lifetimes of three to five years. In [3] yet another disadvantage is presented: the environmental impact, which also needs to be considered. An average computer system requires about 10 times its weight in chemicals and fossil fuels to produce. When it is used, the electricity consumed and heat generated has a major environmental impact. Finally, at end of life, the toxic substances in a computer such as heavy metals and brominated compounds constitute a critical issue. Knowledge of these disadvantages allows for better understanding of the importance of zeroclient architectures. The rest of this article is organized as follows: - In Section 2 a definition and short description of zero-clients and their advantages is realized; - Section 3 is dedicated to the presentation of Parallel - the application we have developed that allows rapid deployment of zero-clients; we list the hardware requirements, describe the deployment scenarios, illustrate its architecture and point out key-features regarding the implementation; - Competitive analysis of Parallel and other existing software which promise zeroclient capabilities are made in section 4; - Section 5 contains plans for future development regarding the extension and improvement of Parallel, conclusions about the impact of our software, and the advantages it has to offer. ISBN:

2 Zero-client computing Zero-clients first appeared with mainframe computing. All computing was centralized and the information was output to multiple users through so called "dumb terminals" [2].

2 2 Zero-client computing Zero-clients first appeared with mainframe computing. All computing was centralized and the information was output to multiple users through so called "dumb terminals" [2]. A zero-client is a set of devices such as a monitor, keyboard and mouse that rely on a centralized CPU for processing. The zero-client connects to the host directly, via a high-performance point-to-point connection, without any network protocol. This configuration is a great platform for small-group systems accessing shared resources. Zero-clients offer smaller costs and a centralized location for upgrade, maintenance and support, effectively reducing licensing and lifetime system costs. Figure 1. Connecting peripherals via existing USB ports 3 Parallel Parallel is a software solution that allows two or more people to use a single computer simultaneously without interfering with one another, as if each of them was using a dedicated PC. It provides a simple and elegant solution to reduce IT costs in computer science laboratories, libraries and businesses, as well as in homes where several family members need to access the PC at the same time. 3.1 Hardware Requirements Parallel supports many standard stations (the exact number depends primarily on hardware limitations) and a main station (the one activated when Windows is started). A video card that is able to support at least two monitors is required. Secondary keyboards and mouse devices can be connected to the host s existing USB ports, or via USB hubs. 3.2 Architecture The core component of our application is the Remote Desktop Protocol. Multiple remote desktop sessions are created, each remote desktop client being displayed full screen on a separate monitor. Keyboard and mouse input is captured by a driver developed specifically for our application. Figure 2. Connecting peripherals via USB hubs ISBN:

3 Figure 3. Parallel main components RDP sessions Input driver The Remote Desktop Connection clients are created using Microsoft s Remote Desktop ActiveX control, which allows us to specify all the attributes that we require: the resolution, whether to start in full-screen or not, the connection details, etc. The difference from normal usage of RDP is that in our case, both the Remote Desktop Connection clients and the Remote Desktop Session Host server are located on the same physical machine. The input received from all the keyboards and mouses connected is filtered based on the device that generated it, and the appropriate input is sent to each remote desktop client window. The challenge here was to intercept and transform the keyboard and mouse input. This can be done with Windows hooks, but if we used them, we would not be able to identify the device from which events are coming from, when connecting multiple keyboards and mouses. On the other hand, Raw Input allows discriminating between input devices, but it does not allow intercepting input. This is why we needed to create a middle layer, an API that provides a simple interface for communicating with kernel-mode components. In this API, data is intercepted in an early stage, before reaching the OS input processing core. The mechanism we developed effectively allows multiple keyboards and mouse devices to be used simultaneously, without interfering with one another, on the same computer. 3.3 Management Parallel Manager allows monitoring and managing the hardware, user sessions, and user accounts. Before applying any changes to the configuration, user accounts that will have access to the RDP sessions need to be created. Either local accounts or Active Directory can be used. The administrator will be able to see the available users, monitors, keyboards and mouse devices, and group them together to form the stations. Once all the stations are configured, with the press of a button, the RDP sessions are created, the input driver is initialized and the computer becomes a multi-seated system. Each station will receive input from the configured keyboard and mouse, and display information on the configured monitor. The peripherals that are not used remain available to be assigned to other stations. Until a device is assigned, it can be used to interact with the host operating system. When a user disconnects, his session remains active until either he or the administrator signs him off. This feature prevents users from losing their work or other important information. The moment a user is signed off, the devices assigned to his station are released and become available to the host operating system. Available devices are reused when creating a new user station. 3.4 Technical Challenges Though conceptually very simple and elegant, implementing Parallel proved to be a significant challenge on the technical side. The low-level component that handles device input required a deep understanding of Windows internals, especially the I/O kernel stack. The implementation language in this case was C. C# and the.net Framework were also used, but their role was only to help implement the user interface. We have used Windows Presentation Foundation and MVVM to create the UI. Visual Studio 2012 was the IDE of choice, while Microsoft Expression Blend helped us concentrate on the user experience and graphical design of the application. Parallel s UI contains a minimal number of controls and is very intuitive. All strings and messages are localized according to the current Language and Regional Settings. Finally, the software development process was based on Test Driven Development. The resulted unit tests provide a greater level of assurance ISBN:

4 regarding the quality of the source code, and the robustness of our application. More technical details regarding the implementation will be provided in a future extended article. 4 Competitive Analysis In [5], it is emphasized that many virtual desktop infrastructure vendors claim to be offering zero clients, but these are usually just thin clients that need additional hardware and software. Many people confuse a zero-client with a thin client endpoint in thin client vendor marketing materials. Real zero-clients do not perform local processing and do not have a client operating system, drivers, storage, etc. Zero-clients should be stateless, management-free, and most importantly, they should mean zero endpoint management. Our software, Parallel offers true zero-client capabilities and has several advantages over its competitors. The main advantage is the ease of installation. Unlike all other similar applications, Parallel can be installed after the operating system is installed, and the installation process is extremely easy to follow. Another feature that is unique to our application is the fact that it detects newly connected devices during runtime and allows the assignment of available resources while other users are still connected. The following table illustrates other key differences between Parallel and other similar software such as Userful (for Linux) and Microsoft Windows Multipoint Server. Parallel Userful Multipoint OS Windows Linux Windows (x64) No. Stations Unlimited Licensing FREE Simple Complex Use Cur. OS Yes Purchase No Domain Join Yes Yes License Setup Time 5 min 30 min 4 hours Performance Fast Fast Slow 3D Graphics Hardware Software No Audio No Yes No USB Access Yes Yes No Table 1: Competitive Analysis 5 Conclusion and Future Development Zero-clients are completely different from current PC infrastructures, and offer a great solution for improving the cost, flexibility, reliability, security and environmental impact of current client-server architectures. From a typical user s point of view, a zero-client can cost as much as 80 per cent less than a PC [6], uses far less energy, and no further investments are necessary to establish the network infrastructure. Zero-clients can replace PCs everywhere, from universities and public institutions to private homes where many family members wish to access a single computer at the same time. Until now, deploying zero-clients required specific hardware and the installation of special operating systems. Parallel, on the other hand, a free and open-source software, requires neither special hardware nor software to be installed, and the installation process is straightforward. Built with user-friendliness, efficiency and high performance in mind, Parallel allows for fast and easy deployment of zero-clients, and real-time management of assets making it unique among its competitors. The main design goals have been reached, but there are still many ideas that have not been implemented in the current version of Parallel, which are planned for future development. We mention here only a few: redirecting multiple microphones, cameras, etc. to the correct remote connection client, and also allowing separate audio streams for each client. Finally, we intend to port the application to Linux as well, as it currently only supports Windows. References: [1] Frank Ohlhorst, Replacing Desktop PCs with Zero-Client Solutions, /Replacing-Desktop-PCs-with-ZeroClient- Solutions / [2] Applica Inc., Zero Client, [3] Wise Technology Inc., Environmental Benefits of Thin Computing, White Paper, [4] Digi International, Zero-Client Computing, White Paper, [5] Pano Logic, Zero-Clients vs. Thin Clients, eviewbody/ /panologic_wp _Zero_vs_Thin_Clients-ZvTC pdf; jsessionid=a6e12b b4d336700c4 [6] Userful, official website, [7] Windows Multipoint Server, official website, ISBN:

5 [8] Centralized vs. Distributed Computing, White Paper Discussion, ites/cbs/siteadmin/documents/centralized%20c omputing%20-%20white%20paper.pdf [9] Autoscript, [10] Windows Pager, official website, [11] Gong Wang, Microsoft Windows Multipoint Server 2010 Reference Architecture for Dell OptiPlex Systems, s/engineering-docs/en/documents/reference- architecture-windows-multipoint-server dell-optiplex.pdf [12] Charles Petzold, Programming Windows, 5 th Edition, Microsoft Press, 1998 [13] Mark Russinovich, David Solomon, Alex Ionescu, Windows Internals, 5 th Edition, Microsoft Press, 2009 ISBN:

ThinManager vs. The Competition

LEARNING SERIES: ThinManager vs. The Competition A comparison in the thin client management market. www.thinmanager.com Customers often ask us to provide some sort of comparison between ThinManager and