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Mobile Code
In distributed computing, code mobility is the ability for running Computer program, programs, code or objects to be data migration, migrated (or moved) from one machine or application to another. This is the process of moving mobile code across the nodes of a Computer network, network as opposed to distributed computation where the ''data'' is moved. It is common practice in distributed systems to require the movement of code or processes between parts of the system, instead of data. Examples of code mobility include scripts downloaded over a network (for example JavaScript, VBScript), Java applets, ActiveX controls, Flash animations, Shockwave movies (and Xtras), and Macro (computer science), macros embedded within Microsoft Office documents. Overview The purpose of code mobility is to support sophisticated operations. For example, an application can send an object to another machine, and the object can resume executing inside the application on the remote machine with the same ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Distributed Computing
Distributed computing is a field of computer science that studies distributed systems, defined as computer systems whose inter-communicating components are located on different networked computers. The components of a distributed system communicate and coordinate their actions by passing messages to one another in order to achieve a common goal. Three significant challenges of distributed systems are: maintaining concurrency of components, overcoming the lack of a global clock, and managing the independent failure of components. When a component of one system fails, the entire system does not fail. Examples of distributed systems vary from SOA-based systems to microservices to massively multiplayer online games to peer-to-peer applications. Distributed systems cost significantly more than monolithic architectures, primarily due to increased needs for additional hardware, servers, gateways, firewalls, new subnets, proxies, and so on. Also, distributed systems are prone to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microsoft Office
Microsoft Office, MS Office, or simply Office, is an office suite and family of client software, server software, and services developed by Microsoft. The first version of the Office suite, announced by Bill Gates on August 1, 1988, at COMDEX, contained Microsoft Word, Microsoft Excel, and Microsoft PowerPoint — all three of which remain core products in Office — and over time Office applications have grown substantially closer with shared features such as a common spell checker, Object Linking and Embedding data integration and Visual Basic for Applications scripting language. Microsoft also positions Office as a development platform for line-of-business software under the Office Business Applications brand. The suite currently includes a word processor (Word), a spreadsheet program ( Excel), a presentation program ( PowerPoint), a notetaking program ( OneNote), an email client ( Outlook) and a file-hosting service client (OneDrive). The Windows version includes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ILOVEYOU
ILOVEYOU, sometimes referred to as the Love Bug or Loveletter, was a computer worm that infected over ten million Windows personal computers on 4 May 2000 and after 5 May 2000. It started spreading as an email message with the subject line "ILOVEYOU" and the attachment "LOVE-LETTER-FOR-YOU.TXT.vbs". Windows computers often hide the latter file extension (" VBS", a type of interpreted file) by default because it is an extension for a file type that Windows knows, leading unwitting users to think it was a normal text file. Opening the attachment activates the Visual Basic script. First, the worm inflicts damage on the local machine, overwriting random files (including Office files and image files; however, it hides MP3 files instead of deleting them), then, it copies itself to all addresses in the Windows Address Book used by Microsoft Outlook, allowing it to spread much faster than any other previous email worm. Onel de Guzman, a then-24-year-old computer science student at A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mobile Agent
In computer science, a mobile agent is a piece of software agent combined with data that is able to migrate from one computer to another autonomously and continue its execution on the destination with the ability to interact with other agents there. Rather than a client requesting data and performing actions, a mobile agent is sent to a server to perform those tasks. This paradigm delegates the work from the client and onto the server. Definition and overview A ''mobile agent'' is a type of software agent, with the feature of ''autonomy'', ''social ability'', ''learning'', and most significantly, ''mobility''. More specifically, a mobile agent is a process that can transport its state from one environment to another, with its data intact, and be capable of performing appropriately in the new environment. Mobile agents decide when and where to move. Movement is often evolved from RPC methods. Just as a user directs a web browser to "visit" a website (the browser merely downloa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Code On Demand
In distributed computing, code on demand is any technology that sends executable software code from a server computer to a client computer upon request from the client's software. Some well-known examples of the code on demand paradigm on the web are Java applets, Adobe's ActionScript language for the Flash Player, and JavaScript. The program code lies inactive on a web server until a user (client) requests a web page that contains a link to the code using the client's web browser. Upon this request, the web page and the program are transported to the user's machine using HTTP. When the page is displayed, the code is started in the browser and executes locally, inside the user's computer until it is stopped (e.g., by the user leaving the web page). Code on demand is a specific use of mobile code, within the field of code mobility. Constraints Client-server The first constraint is that the system must be made up of clients and servers. Servers have resources that clients want ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Remote Evaluation
In computer science, remote evaluation is a general term for any technology that involves transmitting executable software code from a client computer to a server computer for subsequent executing at the server. After the code has finished executing, the results of its execution are sent back to the client. Remote evaluation belongs to the family of mobile code, within the field of code mobility. An example for remote evaluation is grid computing: An executable task may be sent to a specific computer in the grid. After the execution has terminated, the result is sent back to the client. The client in turn may have to reassemble the different results of multiple concurrently calculated subtasks into one single result. See also *Client-side scripting, the client executing code sent by the server, instead of the server executing code sent by the client *Code on demand *Code mobility In distributed computing, code mobility is the ability for running programs, code or objects to be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Process Image
{{Refimprove, date=December 2013 In computing, a system image is a serialized copy of the entire state of a computer system stored in some non-volatile form, such as a binary executable file. If a system has all its state written to a disk (i.e. on a disk image), then a system image can be produced by copying the disk to a file elsewhere, often with disk cloning applications. On many systems a complete system image cannot be created by a disk cloning program running within that system because information can be held outside of disks and volatile memory, for example in non-volatile memory, such as boot ROMs. A system is said to be capable of using system images if it can be shut down and later restored to exactly the same state. In such cases, system images can be used for backup. Hibernation is an example that uses an image of the entire machine's RAM. Process images A process image is a copy of a given process's state at a given point in time. It is often used to create persi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Machine Code
In computer programming, machine code is computer code consisting of machine language instructions, which are used to control a computer's central processing unit (CPU). For conventional binary computers, machine code is the binaryOn nonbinary machines it is, e.g., a decimal representation. representation of a computer program that is actually read and interpreted by the computer. A program in machine code consists of a sequence of machine instructions (possibly interspersed with data). Each machine code instruction causes the CPU to perform a specific task. Examples of such tasks include: # Load a word from memory to a CPU register # Execute an arithmetic logic unit (ALU) operation on one or more registers or memory locations # Jump or skip to an instruction that is not the next one In general, each architecture family (e.g., x86, ARM) has its own instruction set architecture (ISA), and hence its own specific machine code language. There are exceptions, such as the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macro (computer Science)
In computer programming, a macro (short for "macro instruction"; ) is a rule or pattern that specifies how a certain input should be mapped to a replacement output. Applying a macro to an input is known as macro expansion. The input and output may be a sequence of lexical tokens or characters, or a syntax tree. Character macros are supported in software applications to make it easy to invoke common command sequences. Token and tree macros are supported in some programming languages to enable code reuse or to extend the language, sometimes for domain-specific languages. Macros are used to make a sequence of computing instructions available to the programmer as a single program statement, making the programming task less tedious and less error-prone. Thus, they are called "macros" because a "big" block of code can be expanded from a "small" sequence of characters. Macros often allow positional or keyword parameters that dictate what the conditional assembler program gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Program
A computer program is a sequence or set of instructions in a programming language for a computer to Execution (computing), execute. It is one component of software, which also includes software documentation, documentation and other intangible components. A ''computer program'' in its human-readable form is called source code. Source code needs another computer program to Execution (computing), execute because computers can only execute their native machine instructions. Therefore, source code may be Translator (computing), translated to machine instructions using a compiler written for the language. (Assembly language programs are translated using an Assembler (computing), assembler.) The resulting file is called an executable. Alternatively, source code may execute within an interpreter (computing), interpreter written for the language. If the executable is requested for execution, then the operating system Loader (computing), loads it into Random-access memory, memory and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flash Animation
Adobe Flash animation (formerly Macromedia Flash animation and FutureSplash animation) is an animation that is created with the Adobe Animate (formerly Flash Professional) platform or similar animation software and often distributed in the SWF file format. The term Adobe Flash animation refers to both the file format and the medium in which the animation is produced. Adobe Flash animation has enjoyed mainstream popularity since the mid-2000s, with many Adobe Flash-animated television series, television commercials, and award-winning online shorts being produced since then. In the late 1990s, when bandwidth was still at 56 kbit/s for most Internet users, many Adobe Flash animation artists employed limited animation or cutout animation when creating projects intended for web distribution. This allowed artists to release shorts and interactive experiences well under 1 MB, which could stream both audio and high-end animation. Adobe Flash is able to integrate bitmaps and ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ActiveX Control
ActiveX is a deprecated software framework created by Microsoft that adapts its earlier Component Object Model (COM) and Object Linking and Embedding (OLE) technologies for content downloaded from a network, particularly from the World Wide Web. Microsoft introduced ActiveX in 1996. In principle, ActiveX is not dependent on Microsoft Windows operating systems, but in practice, most ActiveX controls only run on Windows. Most also require the client to be running on an x86-based computer because ActiveX controls contain compiled code. ActiveX is still supported in the "Internet Explorer mode" of Microsoft Edge (which has a different, incompatible extension system, as it is based on Google's Chromium project). ActiveX controls ActiveX was one of the major technologies used in component-based software engineering. Compared with JavaBeans, ActiveX supports more programming languages, but JavaBeans supports more platforms. ActiveX is supported in many rapid application development te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
