In computer science, virtualization is a technique for providing access to existing computer resources (CPU, memory, disk space, etc.) by combining or partitioning them so that they behave as one or more operating environments, thus providing access that is superior to the original resource configuration. Virtualization is the transformation of physical resources into logically manageable resources to break down barriers between physical structures. In the future, all resources are transparent, the virtual world runs on a wide variety of physical platforms, the management of resources will be carried out in a logical manner, fully automated allocation of resources, and virtualization technology is the ideal tool to achieve it. Virtualized environments require the coordination of multiple technologies: server and operating system virtualization, storage virtualization, as well as system management, resource management and software submission, and non-virtualized environments consistent with the suite of environments. Because of virtualization, enterprises no longer need to build costly data centers to achieve off-site backup. This is extremely attractive to users.
Basic introduction Chinese name ：Virtualization Foreign name ：Virtualization Introduction, virtual instrumentation, virtual display, virtual machine, CPU, file, desktop, technology classification, hardware mode, mode of operation, semi-virtual technology, drawbacks, advantages, arbitration, technological development, business, medical industry, entertainment industry, urban planning, education field, military field, Introduction Virtual Reality Virtual Reality (VR) is a cross-discipline of virtual technology developed on the basis of computer graphics, computer simulation technology, human-computer interface technology, multimedia technology, and sensing technology, and the research of this technology began in the 1960s. Until the early 1990s, virtual reality technology began as a more complete system and received great attention. Virtual reality is a new way for people to visualize and interact with complex data through computers, and compared with the traditional human-computer interface and the popular Windows operation, virtual reality has made a qualitative leap in technical thinking. The "reality" in virtual reality refers to any thing or environment that exists in the world in a physical or functional sense, which can be practically realized, or practically difficult or impossible to realize. The term "virtual" means computer-generated. Therefore, virtual reality refers to a special computer-generated environment, people can use a variety of special devices to "project" themselves into this environment, and operation, control the environment, to achieve special purposes, that is, people are the master of this environment. The essence of virtual reality is the communication technology between humans and computers, which can support almost any human activity and is applicable to any field. Virtual Instruments National Instruments - The Founder of Virtual Instruments For more than three decades, NI has revolutionized the field of test and measurement and automation through virtual instrumentation: virtual instrumentation integrates commercial off-the-shelf technology with innovative hardware and software platforms to provide a unique solution for embedded design, industrial control, and test and measurement. Virtual Instrumentation offers a unique solution for embedded design, industrial control, and test and measurement. Using virtual instrumentation, engineers can use graphical development software to easily and efficiently create fully customized solutions to meet the trend of flexible requirements - unlike specialized, fixed-function traditional instruments. Today, 85% of Fortune 500 manufacturing organizations have chosen virtual instrumentation to dramatically reduce the size of their automated test equipment (ATE), increasing productivity by as much as ten times at a fraction of the cost of traditional instrumentation solutions. At the same time, virtual instrumentation itself continues to evolve and innovate, building on commercially available technologies and enabling new and emerging technologies to drive virtual instrumentation. also true and false virtual display The purpose of building a virtual reality system is to develop a virtual reality suite, so any one complete virtual reality system needs to have a set of complete functions to look at the confusion of the virtual reality suite of development platforms, which generally includes two parts, one is the development of the hardware platform, that is, the high-performance image generation and processing systems, usually high-performance graphic computer or virtual reality workstations; the other is the development platform, high-performance image generation and processing systems, usually high-performance graphic computer or virtual reality workstations; the other part is the development platform for the virtual reality system. One is hard body development platform, i.e., high performance image generation and processing system, usually a high performance graphic computer or virtual reality workstation; the other part is soft body development platform, i.e., object-oriented application of virtual reality application soft body development platform. This object-oriented virtual reality application software development platform is the most important one, which undertakes the establishment of 3D graphic scene driver and secondary development of application function in the process of virtual reality application development, and is the high-level API of virtual reality application development, and is also the basic platform for connecting VR peripherals, establishing mathematical model and application database, without which it will be impossible to develop a well-functioning virtual reality application. Without it, it will not be possible to develop a fully functional virtual reality application program. Therefore, the development platform part is the core part of the whole virtual reality system, responsible for the development of the whole VR scene, computing, generation, is the most basic physical platform of the whole virtual reality system, at the same time connecting and coordinating the whole system of the other subsystems of the work and operation, and with them *** with the composition of a complete virtual reality system. Therefore, the virtual reality system development platform is indispensable and vital in any virtual reality system. Virtual reality display system. The virtual 3D projection display system is the most important 3D/VR graphic display output system in the whole virtual reality system, the core part of which is the stereoscopic version of the high-brightness projector and related components, which displays the high-resolution 3D/VR scene generated by the VR workstation in a large stereoscopic projection, so that the 3D virtual world to be interacted with is highly realistic in front of the participant's eyes, thus providing the VR user with Provide a group participation, collective viewing, with a high sense of presence of the input type of virtual reality environment, and combined with the necessary virtual peripherals (such as data gloves, 6 degrees of freedom position tracking system or other interactive devices), participants can freely interact and manipulate from different angles and directions, realizing real-time interaction and real-time roaming in the three-dimensional virtual world. In the virtual reality application system, there are usually a variety of display systems or devices, such as: large screen monitors, helmet displays, stereoscopic displays, and virtual 3D projection display systems, and virtual 3D projection display systems are currently the most widely used system, because virtual reality technology requires the application system to have immersive, and among all of these display systems or devices, the virtual 3D projection display system is the system that can best meet this functional requirement. Among all these display systems or devices, the virtual 3D projection display system is the system that can best meet this functional requirement, therefore, this kind of system is also the most popular among the majority of professional simulation users. Virtual three-dimensional projection display system is now the international commonly used virtual reality and visual simulation means and methods of realization, but also one of the most typical, most practical, the highest level of input virtual reality display system. Highly realistic three-dimensional virtual world of high sense of presence and high degree of participation in the end so that the participants really realize the information exchange with the virtual space and the reality of the conception. Very suitable for military simulation training, CAD/CAM (virtual manufacturing, virtual assembly), architectural design and urban planning, virtual biomedical engineering, scientific visualization, teaching demonstration and many other fields ...... Virtual Reality Interactive System, 6 degrees of freedom of real-time interaction is the most essential feature of virtual reality technology and one of the requirements, but also the essence of virtual reality technology. The essence of virtual reality technology, leaving real-time interaction, virtual reality application will lose its value and significance, which is also the most fundamental difference between virtual reality technology and 3D animation and multimedia application. In the virtual reality interactive application, usually with the help of some special virtual peripherals for specific applications, they are mainly 6 degrees of freedom virtual interactive systems, such as: force or haptic feedback system, data gloves, position tracker or 6 degrees of freedom space mouse, joystick and so on. Virtual technology Virtual machines Virtual machine technology is at the forefront of the international anti-virus field. This technology is closer to manual analysis, with a high degree of intelligence and accuracy. First of all, let's describe the work of a virus analyzer: when we get a sample, we don't dare to run it directly, because it may be poisoned, and most likely it is an unknown, new virus that no one can kill. To analyze it, what we must do is trace its execution to see if it has infectious modules and if it has destructive modules. If a sample has modules for infecting, we indisputably recognize it as a virus, and if it also has destructive modules, we categorize it as a malignant virus. Some viruses are theater-filtered, academic, and don't damage the system. However, this is like wearing a pair of shoes that have been soaked in water, which is not a big problem for your feet, but is ultimately uncomfortable for your heart. This brings us to an important issue in determining whether a sample is a virus or not: contagiousness. We can imagine that if we can let the program determine whether a "sample" is infectious or not, we will have solved an important problem in the field of anti-virus "warning". Traditionally, programmers would use the DOS DEBUG program to analyze viruses, but nowadays more people are choosing SOFT-ICE, which is a more powerful software. But at the end of the day, the core of this type of dynamic debugging software is a single-step trace that executes each statement of the program being debugged. In fact, a more specific approach can be this: use the program code to virtualize a CPU, the same also virtual CPU of the various temporary memory, and even the hardware ports will also be virtualized, with the debugging program to adjust the "samples" being tuned to the virtual environment for the execution of each statement, so that we can through the memory and the temporary memory and connectivity ports. This way, we can understand the execution of the program through the changes of the memory and temporary memory as well as the connecting ports. Such a virtual environment is a virtual machine. The future virtual reality technology is based on the virtual machine technology at the bottom level of the system. Since any dynamics of a program can be reflected in a virtual machine, the infectious action of a virus will be reflected if it is executed in a virtual machine. If this happens, the chance of detection of unknown viruses will be 100%! Nowadays, individual anti-virus software selects the first few K bytes of the sample code segment to be executed virtually, and the detection rate is already as high as about 95%. Virtual machines can be used to detect known viruses even faster, with false positives reduced to less than a thousandth of a point! This technology was recognized as the cutting edge of the international anti-virus field in 1997, and many people are still researching and refining it today. Because its future could be a huge artificial intelligent anti-virus robot for use on the Inter. And, of course, a soft robot. Watching Daze CPU CPU virtualization technology is a hard solution, the CPU supporting virtual technology comes with specially optimized instruction sets to control the virtual process, through which the VMM (VirtualMachineMonitor) will easily improve the performance, compared to the soft virtual implementation. approach will improve the performance to a great extent. Virtualization technology provides chip-based functionality that improves purely software-based solutions with VMM-compatible software. Virtualization hardware greatly simplifies VMM design by providing a new architecture that allows the operating system to run directly on top of it, eliminating the need for binary conversion and reducing the associated performance overhead, thus enabling VMMs to be written to a common standard and delivering more robust performance. In addition, there is a lack of support for 64-bit client operating systems in purely software-based VMMs, a serious drawback that is becoming more and more prominent with the increasing popularity of 64-bit processors. CPU virtualization technology supports 64-bit client operating systems in addition to a wide range of traditional operating systems. Virtual seduction File FileVirtualization is the creation of an abstraction layer between file servers and the clients that access those file servers. Once socked away, the FileVirtualization layer manages files and archive systems across servers, allowing administrators to provide clients with a logical archive hookup across all servers. This server continues to host the archive data and metadata. While this arrangement well imagined to unnecessarily increase IT overhead, archive virtualization provides a number of key benefits, including a global namespace for indexing archives on the web archive servers. In addition, this virtualized archive storage consolidation allows for *** enjoyment of access to storage capacity between archive servers. The data migration implemented between file servers is transparent to both end users and applications. This is ideal in a hierarchical storage infrastructure. In short, archive virtualization allows organizations to access isolated storage capacity on networked archive servers and perform seamless archive migration on them. Virtual Machines Archive virtualization can be deployed as a single appliance or an off-the-shelf server running archive virtualization software. This choice is basically determined by cost and the associated level of management and disruption. The most common deployment option is an appliance. Such appliances are available in four different architectures: out-of-band, in-band, a combination of the two, and Split-Path. And for all archives virtualization deployments are successful in the long run. Some organizations may roll back (undo) their deployments. This can be a very disruptive process for archive servers and web-attached storage platforms. In extreme cases, a rollback may require an organization to offload data, remove the archive virtualization layer, and then reformat and reload all of the data. Resellers are often able to help identify potential fallback issues and provide recommendations to mitigate the damage. Users typically test their fallback programs before general deployment. Archive virtualization is limited by scalability. Scalability includes file system, archive, server, or input/output performance. An archive virtualization platform must also be compatible with current infrastructure. This allows it to work with existing storage systems and switches. To prevent potential problems, the archive virtualization platform should be tested frequently for proper scalability and compatibility. Desktop Desktop virtualization generates a brand new virtual image of an existing operating system that has exactly the same functionality as a real windows system. After entering the virtual system, all operations are carried out in this new independent virtual system, can be independently installed and run software, save data, have their own independent desktop. Will not have any impact on the real system. Will not be because the real system problems and affect the virtual system inside the software and data. The main foreign products are MOJOPAC, which can make your iPod, external hard disk, USB flash drive, or any other luxury storage hardware into a "private portable PC" software. MojoPac can put your XP desktop, settings, accounts, and even programs and habit settings into a portable storage device, which can be carried with you. MojoPac can put your XP desktop, settings, accounts, and even programs and custom settings into a portable storage device, which can take your various private data and custom settings to work freely on different machines, and really plug and play. Domestic products are mainly prayaya v3, can be realized in any non-windows system partition, including mobile storage on the installation of a large number of applications, when you are still using other computers every time, but do not have their own want to use the software and agonized over the time, V3 has been to solve your problems! We can install our own commonly used software inside the mobile storage with V3, and in the future, whether you are in the company or on a business trip, as long as you bring a USB flash drive or mobile hard disk with V3, you can plug and play, and all the operation records are kept in the mobile storage, which won't leave any traces in the host computer. Technology Classification Mainstream virtualization technology, the mainstream x86 virtual machine technology mainly has such categories: Hardware model The virtual hardware model establishes an abstract virtualization platform between computer, storage and network hardwares, so that all the hardwares are unified into a single virtualization layer. Today, typical products of this type of virtual machine are Vmware's Workstation, GSX Server, ESX Server and Microsoft's Virtual PC, Virtual Server and Parallels Workstation. Virtual Hardware Mode Features: Virtualizes the Intel x86 platform to run multiple operating systems and applications simultaneously. Hardware-level virtualization is provided through the use of a virtualization layer, where the virtual machine provides a virtual set of Intel x86-compatible hardware for the operating system image running on the virtual machine. This virtual hardware virtualizes all the equipment that a real server has: motherboard chips, CPUs, memory, SCSI and IDE disk devices, various interfaces, displays, and other input and output devices. Moreover, each virtual machine can be independently encapsulated into an archive, allowing for flexible migration of virtual machines. Operating Model The virtual operating system model creates a virtual layer based on the host operating system on which the virtual machine runs, which is used to virtualize the machine's host operating system. On top of this virtual layer, multiple virtual private servers (Virtual Private Server, VPS) can be created that are isolated from each other. These VPSs can maximize the efficiency*** of hardware, software licenses, and management resources. For its users and applications, each VPS platform operates and is managed identically to a standalone host because each VPS can be rebooted independently and has its own root access license, users, IP addresses, memory, processes, files, applications, system libraries, and configuration files. For product servers that run multiple applications and have real data, virtualization of the operating system can reduce cost consumption and increase system efficiency. Today, swsoft's virtuozzo is a mature product in this area. Virtualization Technologies Semi-Virtualization Among the growing list of virtualization technologies, Xen is one of the most notable in recent times. xen was developed as a research project at the University of Cambridge, and it has gained a lot of traction in the open-source community. xen is a semi-virtualizing (paravirtualizing) technology. VMM (Virtual Machine Monitor), which means that the operating system has to be selectively modified in order to invoke the system management program, but the applications running on the operating system do not need to be modified.Xen is a special kind of virtual hardware VM that has most of the characteristics of a virtual hardware VM, with the major difference that Xen needs to Xen is a special type of virtual hardware VM that has most of the features of a virtual hardware VM, with the major difference that Xen requires modifications to the operating system core. Today, Xen only supports Linux VMs implemented on top of Linux systems. However, the new version will support Intel's hardware virtualization technology, Intel-VT, a key technology that will address Xen's difficulties in virtualizing Windows systems. VMware is still the leader in virtualization technology, and it still has a clear advantage over XenSource in terms of product maturity. But many industry insiders believe that Xen will grow stronger as a result of open source. Today, open source giants Red Hat and Novell have begun to integrate the technology into their Red Hat Enterprise Linux 5 systems as well as Novell and SuSE Linux Enterprise Server 10 systems. Cons High cost High hardware costs. High operation and maintenance costs, including data center space, cabinets, cabling, power consumption, air conditioning, and labor costs. Poor compatibility Systems and suites migrating to new hardware require systems that are compatible with older systems. Availability Low availability because each server is a standalone, and it is more costly to configure it as a dual-unit system. System maintenance and upgrades or expansions require downtime and disruptions to the application. Lack of manageability Too many servers to manage, long deployment times for new servers and suites, greatly reducing server rebuild and suite loading times. Hardware maintenance requires days/weeks of change management preparation and hours of maintenance windows. Benefits In a virtual architecture, users can view resources as exclusively theirs, and administrators can manage and optimize the entire resources enterprise-wide. vMware's virtual architecture can reduce enterprise IT spend by increasing efficiency, flexibility, and responsiveness. Managing a virtual architecture allows IT departments to connect and manage resources faster to meet business needs. Benefits include the following: TCO Savings Reduce software and hardware costs by 40% by consolidating multiple physical servers into a single physical server. Consolidation ratios: 10-15:1 for production environments, 15-20:1 for development and testing environments; average utilization per server increased from 5-15% to 60-80%; 70-80% reduction in operating costs, including data center space, cabinets, network cables, power consumption, air conditioning, and labor costs. Improve Service Levels Help your organization establish a relationship between business and IT resources so that IT and business priorities correspond. Manage all servers as a single, unified resource and automate dynamic resource provisioning on demand. On-demand capacity expansion without interruption. Improve Operational Efficiency Deployment time from hourly to minute, server rebuild and nested loading time from 20-40 hrs =>15-30 min, saving 10,000 person-hours (300 servers) per year. Hardware maintenance, which previously required days/weeks of change management preparation and 1-3 hour maintenance windows, can now be performed with zero downtime for hardware maintenance and upgrades. Applying Virtual Technology Virtual technology has been used to train astronauts since the 1970s. Since it is a money-saving, safe, and effective method of training, it is now being extended to training in a wide range of industries. Nowadays, virtual reality has been widely applied in different fields. Virtual reality is a computer-generated three-dimensional space in which users can interact with objects, in addition to viewing, but also in the space with the user's will to freely manipulate the object, which in turn produces a considerable sense of integration and participation. Virtual technology is now being used in many fields such as science and technology, business, healthcare, and entertainment. The development of the Boeing 747 is a typical example of the use of virtual technology. Science and technology development For example, in the science and technology museum, using virtual reality technology, we can truly reproduce the surface of the outer planet stars, demonstration of its structure and movement process; can also be deep into the celestial body, the internal situation of the celestial body through the simulation of the image show, the structure of the sun's interior by other means is very difficult to show, but through the virtual reality technology, but it can be shown realistically. Another example is in the experimental education, only the public hands-on exploration and practice, through the practice of cultivating creative thinking, the dissemination of scientific ideas and scientific methods in order to better achieve the purpose of experimental education. In the past, due to the limitation of various soft and hard conditions in science and technology museums, this is often the most difficult to realize or the most costly. The virtual reality technology for virtual experiments, not only can produce visual effects, but also able to deal with real-time interactive graphics, with graphics other than sound between and touch. The public through the stereo helmet, data suit and data gloves or three-dimensional mouse to operate the sensory device, completely in the virtual world to fully perceive the information, and make choices or corresponding actions. Moreover, switching between different experiments can be done by simply entering different dispositions. There is no need for extensive replacement of external components. Business Virtual technology is often used for sales promotion. For example, when bidding for a construction project, the design is represented in virtual reality, so that the owner can be taken on a tour of the future building, such as the height of the doors, the orientation of the windows, the amount of light, and the interior decoration of the house can be empathetic. It can also be used for tourist attractions and the promotion of goods with many functions and diverse uses. Because the virtual reality technology to show the charm of such goods, more attractive than the text or picture publicity alone. Medical industry Virtual technology applied to the medical industry generally have the following directions. 1, surgical training Future surgeons need to conduct a lot of fine training before really going to the operating table. The virtual reality system can provide the ideal training platform, trained doctors to observe high-resolution three-dimensional human image, and through the tactile workbench simulated tactile, so that trainees in the cutting tissue feel the pressure of the instruments, so that the operator operates the feeling of surgery as in the real human body. Neither cause life-threatening danger to the patient, but also can reproduce high-risk, low-chance surgical cases, which can be repeatedly practiced by the training object. 2、Surgical preview Virtual reality technology can be used to generate virtual images of the patient's actual data, to establish a simulated environment in the computer, the doctor with the help of the virtual environment of the information in the surgical preview, in order to rationalize, quantitative system of the development of surgical programs for the selection of the optimal surgical path to reduce surgical injury, reduce the damage to the adjacent tissues, to improve the accuracy of tumor localization, the implementation of complex surgical procedures and improve the success rate of the operation, and so on. It is of great significance. 3、Clinical diagnosis Pure soft medical virtual reality developed using three-dimensional reconstruction technology has developed a number of virtual endoscopy of the soft body, which can make the doctor's vision in the patient's body and even capillaries in the free navigation. This dynamic display of reality is invaluable for clinical diagnosis. Entertainment Industry The entertainment industry is the most expansive use of virtual technology. A ski simulator is sold in the UK. The user wears a ski suit, has skis on his feet, a ski stick on his hands, a helmet display on his head, and sensors on his hands and feet. Although in the bucket room, as long as you do a variety of skiing action, you can helmet display, see the pile of snow-covered mountains, canyons, cliffs and steep walls, one by one from the side of the swept away, the scene and in the ski resort really skiing feel the same. Virtual reality technology not only creates virtual scenes, but also creates virtual hosts, virtual singers, and virtual actors. Japanese TV station launched the singer DiKi, not only singing and charming style, attracted countless fans have fallen, many stargazers want to see its face, forcing the TV station had to explain that she is just a virtual singer. The United States Disney company is also ready to launch a virtual actor. This will make the "actor" art of youth, vitality forever. Star pay to the sky is another reason for the use of virtual actors. After the virtual actor becomes the main character of the movie, the movie will become a branch of the software industry. Softwares companies will develop countless virtual actor softwares for people to buy. Of course, in terms of humor and human touch, virtual actors will not be able to compare with real actors for a long time or even ever, but it does make for good actors. The recent selection of the heroine of the computer-generated game show Tomb Raider as one of the world's most recognizable characters is a sign that the age of the virtual actor is coming to an end. Urban Planning Urban planning has always been one of the most urgent areas of demand for new visualization technology, virtual reality technology can be widely applied in all aspects of urban planning, and bring tangible and considerable benefits: the immersion and interactivity of the virtual reality system for the presentation of the planning program not only can give the user a strong, realistic sensory impact, to get an immersive experience, but also through its data interface in the real-time virtual environment at any time to access the project, but also through its data interface in the real-time virtual environment. Real-time virtual environment at any time to obtain the project data, to facilitate the planning, design, bidding, approval, management of large-scale complex engineering projects, is conducive to the design and management personnel on a variety of planning and design programs to assist in the design and program evaluation. Avoid design risk virtual reality virtual environment established by the real data based on the establishment of the digital model combination, strict compliance with the standards and requirements of engineering project design to establish realistic three-dimensional scene, the planning project for the real "reproduction". Education With the development of virtual technology and education teaching requirements for the continuous improvement of the means, virtual technology has also begun to enter the field of education, and will become a future development trend. For example, some Internet companies have developed "disaster prevention and mitigation online simulation experience hall", the use of the game allows users (players) to learn disaster prevention and mitigation knowledge while having fun, the online experience hall set up "how to save yourself after an electric shock?" The online experience hall sets questions such as "How to save yourself after an electric shock?" and "How to save yourself and escape from an earthquake?" The online experience hall sets questions such as "How to save yourself after an electric shock?" and "How to save yourself and escape from an earthquake?" to improve the effect of safety education. The future of virtual technology will be more in-depth, more comprehensive into the field of education. So that people in the virtual reality of the situation will learn to survive and develop skills. Virtual technology will also use the effect of realistic virtual education scenes in all aspects, so that education is more intuitive, better results. Disaster prevention and mitigation online simulation experience museum Military field Now the United States, Russia and other countries have been using virtual network game to practice, which makes the new recruits can be in the daily game training in contact with the simulation of the real scene, so that the new recruits can quickly master the new weapons, with the improvement of the military technology, the virtual technology will be in the military field to play a greater role. According to U.S. media reports, the U.S. Army from the "Red Storm Entertainment", "Interactive Magic" and "Timeline" and other famous computer game companies hired a large number of industry experts and masters, specializing in army and government departments to develop training for personnel. A large number of industry experts and masters have been hired by famous computer game companies, such as Red Storm Entertainment, Interactive Magic and Timeline, to develop computer games specifically for the Army and relevant government departments for personnel training and apply them to military training. Since the launch of the United States Army game, the United States Department of Defense conducted a survey on the training of recruits in the 4th Mechanical Infantry Division, the first digital division. The results were that about 40% of the recruits became proficient in complex digitized main battle equipment in only two months. When asked why, the recruits responded that operating these weapons and equipment was similar to the games they played before enlisting.