Networking & tele communication

Management Information System

Presentation On

Tele-communication &

NetworkingMade By:

Rahul Tanwar – 24/025Nikhil Nagpal – 24/019

Objectives In this session, we will learn to:

Identify networks

Classify network architecture

Identify network topologies

Identify the network media

Identify the network devices

Explore the OSI model

Introduction to Networks Is a group of computers and other devices, such as

a PDA or a Printer, connected together with a medium, such as a cable.

Can be created to enable the devices communicate or share resources, such as a file or a printer.

Provides various advantage, such as:I. Data sharingII. Resource sharing

Introduction to Networks (Contd.)

Based on the size and the coverage area, networks are categorized into the following types:

Personal Area Networks (PANs)

Local Area Networks (LANs)

Metropolitan Area Network (MANs)

Wide Area Networks (WANs)

Personal Area Network Is a small network established for communication

between different devices, such as laptops, computers, mobiles, and PDAs.

Extends to typically 10 meters.

Local Area Network Is a small-scale network that extends over relatively

small distances. Connects computers in a room, the floors of a

building, or a campus to share resources and exchange information extending up to a few kilometres.

Metropolitan Area Network Is relatively larger than LAN and extends across a city

or a metropolitan. This is how they derive their name. Is created by connecting two or more LANs located at

different locations in a city.

Wide Area Network Provides network connecting spanning across large

geographical areas, such as across states, countries, or a globe.

Consists of two or more LANs and/or MANs. One of the most prominent examples of the existing

WANs is the Internet.

Just a Minute Internet is the largest _________________.A. PANB. LANC. WAND. MAN

Problem Statement.

Wow, computers can be connected together to form different types of networks. But, how do computers and other devices interact in a

network?

Classification of Network Architecture

The architecture of a network is a logical design that determines how the devices in the network communicate.

The commonly used architectures for computer networks are:

i. Client-server architectureii. Peer-to-peer architecture

iii. Hybrid architecture.

The Client-server Architecture On a network built using the client-server architecture, the

devices communicate to other devices through a central computer referred to as a server.

The server is a terminal with high processing power, which provides services for the other computers on the network.

The client is a terminal that accesses the resources available on a server.

The Peer-to-peer Architecture On a network built using the peer-to-peer architecture, no

specific distinction exists between a client and a server. Any node can provide a service as well as send a request

for a service from another node on the network. The peer-to-peer network architecture allows sharing of

resources, data, and users. Each node on the network has full control over the

network resources.

The Hybrid Architecture A hybrid, in general, is a composition of two different

types of elements. A hybrid network architecture is created to get the

benefits of both, the peer-to-peer and the client-server architectures, in a network.

Just a Minute ________________ is a combination of two basic

network architectures.

A. HybridB. Peer-to-peerC. Client-server

Problem Statement

.

Now, We understand how the devices can interact in a network. But, how

should we place the devices physically in the

network?

Identifying Network Topologies The network technology is a schematic layout or map of

the arrangement of nodes over a network. This layout also determines the manner in which

information is exchanged within the network. The different types of network topologies that can be

used to set up a network are: Bus Star Ring Mesh Tree

Hybrid

Bus Topology The bus topology connects all the nodes on a network to a main

cable called bus. The bus topology requires minimum cabling and therefore the

cost of setting up a network is less. The bus topology is highly prone to faults. Adding nodes to an existing bus topology network is difficult. The length of the cable used for the topology has a physical

limitation of 30 metres.

Star Topology The star topology connects nodes over a network using

a central control unit called the hub You can easily add nodes to a star-based network by

attaching the required nodes to the hub. Setting up a star topology requires a lot of cabling

because all the nodes have to connect to the hub.

Ring Topology The ring topology connects the nodes on a network

through a point-to-point connection. The ring topology prevents network collisions. If one of the nodes on the network malfunctions, the

entire network stops functioning. The devices and cabling, required to set up a ring

network, are more expensive than any other topology.

Mesh Topology The mesh topology involves point-to-point connection

between all the nodes on a network. The mesh topology is highly reliable because network

connectivity does not depend on any one node. The mesh topology requires an elaborate cabling setup

to connect each node within the network to every other node on the network. It involves high installation and setup costs.

Tree Topology The tree topology is created where the nodes are connected

in a hierarchical manner. In tree topology, the device at the root is referred to as the

parent for all the other nodes or devices in the network. The nodes below a parent node are referred to as child

nodes. A tree topology based network is more manageable as the

network is broken into parts.

Hybrid Topology The hybrid topology can be a combination of two or more

basic topologies, such as bus, ring, star, mesh, or tree. Hybrid networks combine more than two topologies,

which, in turn, enable you to get advantages of the constituent topologies.

Just a Minute In which one of the following topologies are all the

nodes connected to each other?A. Mesh topologyB. Ring topologyC. Star topologyD. Bus topology

Network Media Is the physical channel that connects network

components, such as nodes and printers. Determines the speed and connectivity of the

network, the resulting overall performance of the network, and the investment required to set up the network.

The two types of network media are:I. Cables

II. Wireless Based on the preceding media, you can form the

following types of network:1. Wired

2. Wireless

Wired Network Cables are the conventional media that are used to

set up wired networks. One of the major concerns in cabling is the

environment in which the cables are set up. In electro-magnetic sensitive areas, the type of

cables used should be such that the transmissions are protected against Electro-magnetic Interference (EMI) or are at a distance from the radiation.

The following types of cables are available to set up a wired network:

i. Twisted pair cableii. Coaxial cable

iii. Fiber optic cable

Twisted pair cables Use copper wires, which are good conductors of

electricity, to transmit data. Contain multiple pairs of wires that are twisted around

each other at regular intervals. This twists negate the electro-magnetic field and reduce network crosstalk.

Are easy to set up, economical, and widely available media for network transmission.

Cannot be used in areas where network security is crucial or the network setup is close to electronically sensitive equipment that may prove to be a potential source of EMI.

Coaxial cables Consists of the following conductors that share a common

axis: Centre conductor: Transmits data Outer conductor: Protects this centre conductor from EMI,

ensuring that data transmission is not disrupted. Provide effective protection against EMI during data

transmission. Are easy to install as compared to twisted pair cables and

support higher transmission rates (10 Mbps and above).

Fiber optic cables Are based on the fibre optic technology, which uses

light rays or laser rays instead of electricity to transmit data.

Are suitable for transmitting data in areas that are prone to high levels of EMI or for long distance data transmissions, where electrical signals may be significantly distorted and degraded.

Including the light-conducting fibre, cladding, and insulator jacket.

Categories:I. Single mode cablesII. Multimode cables.

Just a Minute Which cable uses light rays instead of electricity to

transmit data?A. Unshielded twisted pair cableB. Shielded twisted pair cableC. Fibre optic cableD. Coaxial cable.

Wireless Network Helps connect distant networks without needing to

physically set up cables between the destination and source points.

Uses the atmosphere to transmit and receive signals in the form of electro-magnetic waves through the antenna.

The electro-magnetic waves can be transmitted through different types of wireless transmission carriers, which include the following:

Radio Microwave Bluetooth

Radio transmission Use electro-magnetic waves for transmitting audio

signals, video signals, and data. Are only limited to low transmission capacities, from

1 Mbps to 10 Mbps. Are susceptible to EMI and eavesdropping, which

allow outsiders to tap into an on going transmission.

Microwave Sends data over a higher bandwidth than radio

transmissions. Is affected by atmospheric conditions, such as rain

and fog. Is also susceptible to EMI and eavesdropping.

Bluetooth Is a network standard that defines how two Bluetooth-

enabled devices transmit data using short-range waves.

Establishes communication between the devices that are within 10 metres of range.

Transfers data at a rate of 3 Mbps.

Just a Minute Which one of the following wireless media can

transmit data only between devices within 10 metres of range?

A. MicrowavesB. Radio wavesC. Bluetooth

Problem Statement.

Is it that we can set up a network only by using network media? Or, we

require some other devices also?

Network Devices In a large network, such as MAN, connecting computers

with each other directly through cables is difficult. In such cases, we need hardware devices to set up a

network. These devices are collectively known as

communication devices. The commonly used communication devices in a

network are: Hub

Switch Router Bridge

Hub Is a central network device used to connect multiple

nodes to form a single network. Broadcasts the received data packet to all devices in

the network. Causes security problems because all the nodes can

read the data packet. Raises collision when two nodes simultaneously send

the data packet to it.

Switch Inspects the data packet before transmitting it to the

computers in the network, determines its source and destination devices, and forwards it accordingly.

Performs better than a hub on a busy network.

Router Connects two logically different networks, such as LAN

and WAN. Sorts and sends data packets to their destinations

based on their Internet Protocol (IP) address. Contains a routing table that decides the route of a

data packet.

Bridge Connects network segments to each other. Examines each packets for its destination information

and forwards only those data packets that are specific to other segments instead of sending all the data packets.

Helps reduce the overall network traffic between the two segments.

Enables the smooth functioning of the network in the event of a breakdown of a particular segment.

Introduction to the OSI Model The OSI model is a standard model used to

communicate between two computers in a network. The OSI model has seven layers. The following are the seven layers of the OSI reference

model. Application

Presentation Session

Transport Network Data-link physical

An insight of the OSI Model Layer Application layer: Provides an interface between the

user and the network. It supports a number of software programs and end-user processes that act as a link between the user and the network.

Presentation Layer: Encodes and decodes data in a mutually agreeable format.

Session Layer: Establishes, manages, and synchronizes the communication between two communicating nodes.

Transport Layer: Segments and reassembles data. Network Layer: Provides a unique address to each node

on a network and controls network traffic. Data-link Layer: Provides a unique identity to each node

on the network. Physical Layer: Transmits data over a communication

channel or a transmission medium.

Just a Minute Which one of the following layers does control the

network traffic?A. The Internet layerB. The Transport layerC. The Application layerD. The Network layer.

THANK YOU..!!!.