Computer Networking
Networking is the concept of sharing resources and services.
A network of computers is a group of interconnected systems sharing resources and interacting using a shared communications link.
A network, therefore, is a set of interconnected systems with something to share.
The shared resource can be data, a printer, a modem, or a service such as a database or an email system.
The individual systems must be connected through a pathway (called the transmission medium) that is used to transmit the resource or service between the computers.
All systems on the pathway must follow a set of common communication rules for data to arrive at its intended destination and for the sending and receiving systems to understand each other.
The rules governing computer communication are called protocols.
Characteristics of a Network
(a) A resource to share (resource)
(b) A pathway to transfer data (transmission medium)
(c) A set of rules governing how to communicate (protocols).
Characteristics of a Network
(a) A resource to share (resource)
(b) A pathway to transfer data (transmission medium)
(c) A set of rules governing how to communicate (protocols).
Types of Network Computing
1) Centralized Computing
The centralized computing model is where all processing takes place in the central mainframe computer.
Terminals are connected to the central computer and function only as input/output devices.
An example of centralized computing to which everyone can relate is using an ATM machine. ATMs function as terminals.
All processing is done on the mainframe computer to which the ATMs are connected.
All processing is done on the mainframe computer to which the ATMs are connected.
2) Distributed Computing
PCs enable individuals to work at their own computers rather than through a single large computer.
Distributed computing involves multiple computers capable of processing independently.
Task completion by the local computer or other computers on the network
3) Collaborative Computing
Collaborative computing enables computers in a distributed computing environment to share processing power in addition to data, resources, and services.
In a collaborative computing environment, one computer might borrow processing power by running a program on another computer on the network. Or, processes might be designed so they can run on two or more computers.
Collaborative computing cannot take place without a network to enable the various computers to communicate.
Types of Network Models
Types of Network Models
a) Client/Server-Based Networking
A client/server network consists of a group of user-oriented PCs (called clients) that issue requests to a server.
The client PC is responsible for issuing requests for services to be rendered.
The server's function on the network is to service these requests.
Some common server types include file servers, mail servers, print servers, fax servers, and application servers.
b) Peer-To-Peer Networking
A peer-to-peer network consists of a group of PCs that operate as equals.
b) Peer-To-Peer Networking
A peer-to-peer network consists of a group of PCs that operate as equals.
Each PC is called a peer.
The peers share resources (such as files and printers) just like in a server-based network, although no specialized or dedicated server machines exist.
