Server components

The cheat/server model oftea allows easier iategratioa with other aetwork apphcatioas (eg, fiaance, project management, or human resources) which typically operate ia the environment of the server component of the cheat/server system. Gheat/server can be gradually iatroduced ia an existing minicomputer environment, often with httie adverse incremental impact ia terms of retraining and additional cost. 

Server components typically implement significant business functions and mn on a server. In a multitier architecture, most business logic in an application runs on dedicated servers... 

Deployment descriptor A description of the preceding parts and additional attributes such as transactional and security behaviors that can be decided at deployment time rather than in the code for the main server component itself. 

Java presents a compelling technical base for component-based development, including enterprise-scale server components. Its main drawback is the single-language model, which is addressed by the integration of Java and CORB A. 

As soon as a move command is available in the queue, a component of the motion server processes it and generates a new instruction for the motion controller. Upon receipt of the instruction, the motion controller moves the stage to the desired position. The server component involved in this task is different from the component involved in previous EtE flow. More importantly, both are not connected with each other for this particular task. Since the flow specifications of both components are not linked with each other, according to the AADL specification they can not be a part of a single EtE flow. Hence, this results in another EtE flow starting from the motion server and ending with the motion controller. The specification of this flow can be seen in Figure 2. 

The server component of the application is based on open-source software solutions, due to which the system is flexible and allows for simple data update as well as addition of functionality and possible expansions of the existing dataset... 

For example, an application that reads stock figures from a newsfeed can be wired up to a spreadsheet this component does some calculations and passes the results to a database, from which a Web server extracts information on demand. Each of these components may be a stand-alone application, perhaps even with its own user interface, but is provided with a way to interact with other software. 

In some situations it can be useful to further distinguish the specification of a component, an executable that implements that spec, a particular installation of that executable, and a running incarnation of that executable that is available as a server. We will use the term component loosely to include all these. A tool or metamodel that dealt more fully with component deployment and management would separate them. 

For components to be plug-replaceable, it is essential that the component specs be self-contained and symmetrical it is the only way to be able to design reliably using parts without knowledge of their implementations. In contrast, a traditional server, in a client-server setting, is one-sided It provides a set of services, but the services it expects from others are not documented explicitly. Object-oriented languages have also focused almost exclusively on services implemented by a class without any explicit description of the services it expects from other objects. 

In simple cases, persistence can be achieved by a protocol by which a component instance serializes itself into a stream that is managed by its container. For larger, server-side components, each component can manage its own persistent storage and transactions effective composition now requires that the container be able to coordinate nested transactions that cross its subcomponent boundaries. Enterprise JavaBeans, CORBA, Microsoft Transaction Server, and COM+ provide their own versions of this... 

The granularity of the components and the corresponding unit of pluggability from monolithic systems, to client-server partitions, to the operating system and its services, to today s object-based component approaches. 

The effort and ease of dynamically connecting components to compose larger systems, from writing screen-scrapers for host-based systems (discussed in a moment) to creating complex applications by visually configuring and connecting server-side components to one another and to user interfaces. 

This is changing substantially, with mainframe applications reborn as server-side components using technologies such as Enterprise JavaBeans. 

Web server This tier forwards appropriate requests to a servelet, a request handler that uses a standard API to plug in to the Web server. It translates CGI-encoded requests into proper method calls using distributed object invocations on an enterprise component. Then it formats and returns the results to the client. 

The technical architecture Apackage structure (for static dependencies) and collaborations (across technology components, such as UI, business object servers, and databases). These cover all domain-independent parts of the system hardware and software platforms infrastructure components such as middleware and databases utilities for logging, exceptions, start-up, and shutdown design standards and tools and the choice of... 

The component descriptions here typically belong to different domains than the primary business problem at hand. Database components are described by generic models of tables, columns, and keys (or types, classes, attributes, and IDs) transaction servers are described by transactional object, recoverable object, and resources communication components could have sessions, channels, and messages user-interface components have buttons, lists, panels, and scrollbars. 

Each component could be in a separate machine if required (as in client-server and the Web). 

Encapsulate persistence mechanisms in a small number of platform-dependent objects with platform-independent interfaces. Separate out technology-dependent infrastructure components that serve primarily to connect other components, such as message queues, transaction servers, ORBs, and databases. 

The legacy system might be only a file server or a relational database. Or it might be a higher-level component, such as a spreadsheet with an API, or a complete application such... 

Wireless data communications devices are used to enable transmission of data between computer systems and/or between a SCADA server and its sensing devices, without individual components being physically linked together via wires or cables. In industrial chemical processing systems, these devices are often used to link remote monitoring stations (i.e., SCADA components) or portable computers (i.e., laptops) to computer networks without using physical wiring connections. 

Of course, there are limitations to this approach that must be kept in mind. First, because we use commercially available components for the data visualization, we are tied to the standard file formats. For the most part these formats are sufficient, but in certain cases they can be limiting. For example, there is no standard for handling multiple entries for a single data field. This becomes an issue when retrieving assay results, because in many cases more than one experiment has been run. Second, this system requires a robust and fast network since many file uploads and downloads to the server are involved. However, in practice we have found these issues to be manageable. 

Contributor factories combine source and server factory principles. They primarily serve specific national or regional markets but also become focal points for certain production processes, components or products. 

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