Introduction to Computer Networks Network Types Topology Topics

Introduction to Computer Networks • Network • Types • Topology

Topics to be Discussed Computer Network Advantages of Networking Disadvantages of Networking Applications of Networks Network Topology Diagram of network topology Bus Topology Star Topology Ring Topology Mesh Topology

Computer Network A network can be defined as two or more computers connected together in such a way that they can share resources. The purpose of a network is to share resources.

Cont…. . A network is simply a collection of computers or other hardware devices that are connected together, either physically or logically, using special hardware and software, to allow them to exchange information and cooperate. Networking is the term that describes the processes involved in designing, implementing, upgrading, managing and otherwise working with networks and network technologies. back

Diagram of computer Network

Advantages of Networking Connectivity and Communication Data Sharing Hardware Sharing Internet Access Sharing Data Security and Management Performance Enhancement and Balancing Entertainment back

Disadvantages of Networking Network Hardware, Software and Setup Costs Hardware and Software Management and Administration Costs Undesirable Sharing Illegal or Undesirable Behavior Data Security Concerns

Applications of Networks Ø Resource Sharing Ø Hardware (computing resources, disks, printers) Ø Software (application software) Ø Information Sharing Ø Easy accessibility from anywhere (files, databases) Ø Search Capability (WWW) Ø Communication Ø Email Ø Message broadcast Ø Remote computing Ø Distributed processing (GRID Computing) back

Network Topology Ø The network topology defines the way in which computers, printers, and other devices are connected. A network topology describes the layout of the wire and devices as well as the paths used by data transmissions. back

Diagram of network topology back

Bus Topology Ø Commonly referred to as a linear bus, all the devices on a bus topology are connected by one single cable. back

Star Topology Ø The star topology is the most commonly used architecture in Ethernet LANs. Ø When installed, the star topology resembles spokes in a bicycle wheel. Ø Larger networks use the extended star topology also called tree topology. When used with network devices that filter frames or packets, like bridges, switches, and routers, this topology significantly reduces the traffic on the wires by sending packets only to the wires of the destination host. back

Ring Topology Ø A frame travels around the ring, stopping at each node. If a node wants to transmit data, it adds the data as well as the destination address to the frame. Ø The frame then continues around the ring until it finds the destination node, which takes the data out of the frame. Ø Single ring – All the devices on the network share a single cable Ø Dual ring – The dual ring topology allows data to be sent in both directions. back

Mesh Topology Ø The mesh topology connects all devices (nodes) to each other for redundancy and fault tolerance. Ø It is used in WANs to interconnect LANs and for mission critical networks like those used by banks and financial institutions. Ø Implementing the mesh topology is expensive and difficult. back