Internet& network

Internet & network

What is a internet??

The internet is a global system of inter connected millons of computer

internet use the stranded internet protocol suite to link several billon devices world wild it is connecting every places, countries to exchange of data ,news and opinions

Advantages of internet…..

Global audience Accessibility Operates 24 hours 7 days a week Relatively inexpensive Communication Information education Entertainment advertising

History of internet In 1969,the US department of defense started a project to allow researchers and military personnel to communicate with each other in a emergency

The project was called ARPANET and it is the foundation of internet After 1970’s ARPANET grows to 30 nodes First e-mail message sent in 1970 After 1990 launch world wild web (www)

What is World wild web

"WWW" and "The web" redirect here. For other uses of WWW, see WWW (disambiguation). For other uses of web,

see Web (disambiguation).The World Wide Web (abbreviated as WWW or W3,commonly

known as the Web) is a system of interlinked hypertext documents that are accessed via the Internet. With a web browser, one can view web pages that may contain

text, images, videos, and other multimedia and navigate between them via hyperlinks.

Web browserA web browser (commonly referred to as a browser) is a

software application for retrieving, presenting and traversing information resources on the World Wide

Web. An information resource is identified by a Uniform Resource Identifier (URI/URL) and may be a web

page, image, video or other piece of content. Hyperlinks present in resources enable users easily to

navigate their browsers to related resources.

Internet protocol

The Internet Protocol (IP) is the principal communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet.

IP, as the primary protocol in the Internet layer of the Internet protocol suite, has the task of delivering packets from the source host to the destination host

solely based on the IP addresses in the packet headers. For this purpose, IP defines packet structures that encapsulate the data to be delivered. It also

defines addressing methods that are used to label the datagram with source and destination information.

Why is the internet so important in our daily lives?

Electronic devices, multimedia and computers are things we are faced with everyday. They are a big

influence in our daily lives. we used to email, fax and all tings work to internet for our life

World wild web usage

Worldwide Internet users 2005 2010 2013

World population 6.5 billion 6.9 billion 7.1 billion Not using the Internet 84% 70% 61% Using the Internet 16% 30% 39% Users in the developing world 8% 21% 31% Users in the developed world 51% 67% 77%

Routing and service tiers

Internet service providers connect customers, which represent the bottom of the routing hierarchy, to customers of other ISPs via other higher or same-tier networks. At the top of

the routing hierarchy are the tier 1 networks, large telecommunication companies that exchange traffic directly with each other via peering agreements. Tier 2 and lower level networks buy Internet transit from other providers to reach at least some parties on the global Internet,

though they may also engage in peering. An ISP may use a single upstream provider for connectivity, or implement multihoming to achieve redundancy and load balancing. Internet

exchange points are major traffic exchanges with physical connections to multiple ISPs.

Types of web sites

Commercial websites Community websites Educational websites News websites

URL (uniform resource locator)Http://www.infortec-international.com/index.html

Protocol host name file name

“an address that point to a particular document or other resource on the internet used most frequently on the world wild web”

network

What is a network

“network is interconnection collection of computer for pupors of sharing

resources and communication”

A network is mead up with following components

1. Computer2. Transmissions media3. Interface4. protocols

Types of network

1. LAN - local area network2. MAN- meteorite area network

3. WAN - wide area network

Others types of network

1. PAN-personal area network2. CAN-camp area network

3. GAN-global area network

Network architectures'

Peer to peer architecture

all are client No special configuration Client o/s

Local users

CLIENT SEVER ARCHITECTURE

• Client severs available• Has special configuration

• Domain user account• Client o/s

Modes of communication

SimplexHalf duplexfull duplex

Communication mediaTransmission media

Guided media Twisted pair cable

Coaxial cable Fiber optics cableUnguided media

Radio waves Microwaves Satellite Bluetooth

Network Topologies

Network topology is the arrang

ement of the various elements

(links, nodes, etc.) of a

computer network. Essentially,

it is the topological structur

e of a network and may be

depicted physically or logical

ly.

Physical topologies

The cabling layout used to link device

s is the physical topology of

the network. This

refers to the layout of cablin

g, the locations of nodes, and

the interconnections

between the nodes and the cabl

ing. The physical topology of

a network is determined by

the capabilities of the networ

k access devices and media, th

e level of control or fault

tolerance desired, and the cos

t associated with cabling or t

elecommunications circuits

.

Logical topologies

The logical topology in contra

st, is the way that the signal

s act on the network media,

or the way that the data passe

s through the network from one

device to the next without

regard to the physical interco

nnection of the devices. A net

work's logical topology is

not necessarily the same as it

s physical topology

basic topologiesBus network topology

Star network topology

Ring network topology

mesh topology

tree topology

End the

presentation

Presentati

on

design

eshani

anuththara

14NU0513