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Mobile Code
In distributed computing, code mobility is the ability for running programs, code or objects to be migrated (or moved) from one machine or application to another. This is the process of moving mobile code across the nodes of a 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 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 state as it had in the originating application. According to a classificat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Distributed Computing
A distributed system is a system whose components are located on different networked computers, which communicate and coordinate their actions by passing messages to one another from any system. Distributed computing is a field of computer science that studies distributed systems. The components of a distributed system interact with 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 massively multiplayer online games to peer-to-peer applications. A computer program that runs within a distributed system is called a distributed program, and ''distributed programming'' is the process of writing such programs. There are many different types of implementations for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Machine Code
In computer programming, machine code is any low-level programming language, consisting of machine language instructions, which are used to control a computer's central processing unit (CPU). Each instruction causes the CPU to perform a very specific task, such as a load, a store, a jump, or an arithmetic logic unit (ALU) operation on one or more units of data in the CPU's registers or memory. Early CPUs had specific machine code that might break backwards compatibility with each new CPU released. The notion of an instruction set architecture (ISA) defines and specifies the behavior and encoding in memory of the instruction set of the system, without specifying its exact implementation. This acts as an abstraction layer, enabling compatibility within the same family of CPUs, so that machine code written or generated according to the ISA for the family will run on all CPUs in the family, including future CPUs. In general, each architecture family (e.g. x86, ARM) has its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ILOVEYOU
ILOVEYOU, sometimes referred to as Love Bug or Love Letter for you, is a computer worm that infected over ten million Windows personal computers on 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." At the time, Windows computers often hid 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 resident of Manila, Philip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Java Agent Development Framework
Java Agent Development Framework, or JADE, is a software framework for the development of intelligent agents, implemented in Java. JADE system supports coordination between several agents FIPA and provides a standard implementation of the communication language FIPA-ACL, which facilitates the communication between agents and allows the services detection of the system. JADE was originally developed by Telecom Italia and is distributed as free software. Resume JADE is a middleware which facilitates the development of multi-agent systems under the standard FIPA for which purpose it creates multiple containers for agents, each of them can run on one or more systems. It's understood that a set of containers constitutes a platform. JADE provides: * An environment where JADE agents are executed * Class libraries to create agents using heritage and redefinition of behaviors * A graphical toolkit to monitoring and managing the platform of intelligent agents History JADE was i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aglets
Aglets is a Java-based mobile agent platform and library for building mobile agents based applications. An aglet is a Java agent which can autonomously and spontaneously move from one host to another carrying a piece of code with it. It can be programmed to execute at a remote host and show different behaviours at different hosts. Java based security implementations take care of authorised access to local resources at the remote hosts. Aglets was originally developed by Mitsuru Oshima ("") and Danny Lange at the IBM Tokyo Research Laboratory. The original name of the project was AWB (Aglets WorkBench) and IBM was responsible for most of the 1.x release. However the project is now hosted at SourceForge.net as an open source project, where it is distributed under the IBM Public License. In the beginning, the SourceForge releases had been only bug-fix ones, but 2.x series (most of which came from open source community only) had better security and thread management. It now incl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mobile Agent
In computer science, a mobile agent is a composition of computer software and data that is able to migrate (move) from one computer to another autonomously and continue its execution on the destination computer. In reality, the mobile agent is the code/object on the move which travels in its itinerary within the network of connected nodes. 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 an Internet browser to "visit" a website (the browser merely downloads a copy of the site, or one version of it in the case of dynamic web sites), a mobile agent ... [...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 wan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Remote Evaluation
In computer science, remote evaluation is a general term for any technology that involves the transmission of executable software code from a client computer to a server computer for subsequent execution 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 objec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Process Image
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 file. 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. Disk images {{Main article, Disk image If a system has all its state written to a disk, then a system image can be produced by simply copying that 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 like boot ROMs. 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 persistence within an otherwise vola ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microsoft Office
Microsoft Office, or simply Office, is the former name of a family of client software, server software, and services developed by Microsoft. It was first announced by Bill Gates on August 1, 1988, at COMDEX in Las Vegas. Initially a marketing term for an office suite (bundled set of productivity applications), the first version of Office contained Microsoft Word, Microsoft Excel, and Microsoft PowerPoint. Over the years, 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. It contains a word processor (Word), a spreadsheet program ( Excel) and a presentation program (PowerPoint), an email client ( Outlook), a database management system ( Access), and a desktop publishing app (Publish ... [...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 execute. Computer programs are one component of software, which also includes documentation and other intangible components. A computer program in its human-readable form is called source code. Source code needs another computer program to execute because computers can only execute their native machine instructions. Therefore, source code may be translated to machine instructions using the language's compiler. (Assembly language programs are translated using an assembler.) The resulting file is called an executable. Alternatively, source code may execute within the language's interpreter. If the executable is requested for execution, then the operating system loads it into memory and starts a process. The central processing unit will soon switch to this process so it can fetch, decode, and then execute each machine instruction. If the source code is requested for executio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
