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Computing Models and Network Development

Computer networking technologies are generally based on the following computing models:
·         Centralized computing
·         Distributed computing
·         Collaborative computing

In addition, the following computing models are used to categorize the way networking services are provided:

·         Client /Server
·         Client/Network
Centralized Computing
In a purely Centralized model, all computing resources reside at the primary Datacenter/Mainframes. This includes Domain Authentication Services, Email, Applications, and Share Files. Remote Sites would access these resources using Terminals/Thin Client devices (as opposed to PCs) and bandwidth-friendly enablers such as Citrix XenApp, Microsoft Terminal Services, or VMware Virtual Desktop technologies.
In Centralized computing, the mainframes provide all the data storage and computational abilities; the Terminal is simply a remote input/output device.
Distributed Computing
In distributed computing, personal computers (PCs) have their own processing capabilities. In this model the application is divided into tasks, and each task is assigned to a computer for processing. The results of the processing can be sent as data to other computers.
Collaborative computing
Collaborative computing (also called cooperative processing) is a type of distributed computing using networked computers that “collaborate” by sharing processing abilities. It is aform of Distributed computing that allows task to be shared by by computers as needed. In  Collaborative computing model two or more computers can share the same task, where as Distributed computing assigns each task to a single computer.

Client/Server Computing

In Client/server computing model, several clients (PCs) are connected to a server
In this model:
·         Processing capabilities are distributed across multiple machines.
·         Clients request services from server.
·         The server performs some of processing for the client.
Client/Network Computing


In Client/Network computing model, users lg in to a network and connect to a set of services rather than to a specific server. These services can be provided through a directory services approach.

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