02-04-2011, 10:42 AM
Presented By:
CHAVA NITHIN
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ADVANCES IN INTERNET COMMUNICATIONS
INTRODUCTION
A)INTERNET ORIGIN
1) PACKET SWITCHING:
Packets are units of electronic information or data while switching refers to the way that packets are transmitted over a network. Under this theory information would continue to flow even if some paths to a particular destination became unavailable.
2) BUILDING THE ARPANET
3) IMPROVING COMMUNICATION:
As the ARPANET expanded the growing community of network users began developing new applications. One experiment that took
place in 1971 was the introduction of working email program.
4) CONNECTING THE NETWORKS
ARPANET was no longer the only packet switching network in existence. A number of companies adopted the technology to create different types of computer networks. Each network was different working within its
own protocols, hardware and software B) INTERNET ARCHITECHTURE
TCP/IP: TCP breaks down and reassembles the packets whereas IP is responsible for ensuring the packets are sent to the right destination. TCP is responsible for the data delivery of a packet and IP is responsible for the logical addressing. IP obtains the address and TCP guarantees delivery of data to that address.
ROUTERS: They are the traffic cops of the internet. They open the IP packets of data to read the destination address, calculate the
best route and then send the packet toward its final destination. When routers determine the next router to receive packets factors like
traffic congestion and the number of hops come into play. They have 2 or more physical ports: receiving (input) and sending(output)
INVENTION OF WORLD WIDE WEB
A)CREATING WEB ADDRESSES
B)SURFING AND SEARCHING THE WEB:
The first graphical user interfaces (GUI) for the web which appeared in 1993 were known as web browsers.
C)TRANSFORMING THE INTERNET
HOW THE INTERNET WORKS
A)PACKET SWITCHING: All information sent over the internet is broken into packets and these packets are sent separately through any number
of different routes to their final destination.
B)PROTOCOLS: All computers connected to the internet operate on a set of rules or protocols: TCP or IP
C) COMMUNICATING ON THE INTERNET
D) THE WORLD WIDE WEB
APPLICATIONS
ONLINE LEARNING
E COMMERCE
INTERNET MARKETING AND
BUSINESS TECHNOLOGY
E SERVICE
INTERNET JOB SEARCHING
BLOGGING
SOCIAL NETWORKING
INTERNET TOOLS
A)TELNET: From your own home or office you can log on to another computer, issue commands just as if you were at that computer’s
Keyboard and then gain access to all the computer’s resources. You do this with TELNET. It follows a client/server model. Distant computer
is called host.
B) FILE TRANSFER PROTOCOL
Many tens of thousands of files are downloaded every day over internet. Most of these files are downloaded using FTP.You can also upload files from your computer to another computer on the internet.
C)JAVA: Java programs run inside your web browser if you have java enabled browser such as Netscape.
D) ACTIVEX: ActiveX ,a technology from Microsoft enables internet programmers to create programs referred to as ActiveX controls or components.
E)JAVA SCRIPT: It is a scripting language that is less complex and therefore much easier to learn than Java and ActiveX.
CGI SCRIPT: It refers to the communications protocol by which a web server can communicate with other applications.CGI application sometimes called a script is used to enable web users to access databases or get information from forms people fill out.
IMPACT OF INTERNET ON
SOCIETY
The internet has revolutionized communication in modern life. Email is fast, cheap and easy to use which has made it the primary form of
communication for many people. Internet Relay Chat(IRC) and instant messaging(IM) are two important internet communications. It has also
produced a number of drawbacks including criminal activity and invasion of privacy.The Internet enables criminals to target larger numbers of victims more quickly and at greater distances ever before. Cybercriminals take
form as hackers who break into computer systems to steal information. One of the most common sources of viruses are files attached
to email messages which automatically send copies of themselves to everyone on an infected computer’s email address list.
INTERNET SECURITY
A)FIREWALLS: They are hardware and software combinations that are built using routers, servers and a variety software. One of the simplest kinds of firewalls utilizes packet filtering. A proxy server also used in firewalls is server software that runs on a host in a firewall such as a bastion host.
B)CRYPTOGRAPHY,PRIVACY AND
DIGITAL CERTIFICATES:
There are 2 kinds of encryption systems: Secret key cryptography and public-key also called asymmetric cryptography. In public-key two keys are involved: public and private. Digital certificates use encryption to
verify that person sending info is really the same or not. They are issued by certificate authorities.