The Internet Is A Largest Computer Network

Published Date: 02 Nov 2017

Introduction

The Internet is a largest computer network that connecting billions of computer users in the world. The word internet is come from between the interconnection and network. There are more than 100 countries are connected into exchanges of information, data, news and opinions. The Internet is dispersed by design which is different wih online services which are centrally controlled, Each Internet computer is independent which is called as a host. Its operators can select which local services and which Internet services to use to make available to the worldwide Internet community. Unusually, this revolution by design works exceptionally well. There are a variety of ways to access the Internet. Most online services offer access to some Internet services. It is also possible to gain access through a profitable Internet Service Provider (ISP) which  is a secure that offers subscribers connect to the internet. The connection between the global network with Internet enabled device is performed through a particular digital data transmission technology. It represents the transfer of information packets through an Internet Protocol route. By connected to the internet, people can easily use the services which provided in the internet. There are services provided in internet such as electronic mail, internet relay chat, news group. These services allow people to share information easily.

Objective of the research

The objective of the assignment is discuss and explain the services which provided in the internet. Since that now the internet is open to everyone in the world, anyone with internet access may launch the internet. They use internet for the purpose of sharing information. This assignment explain the terms of internet, history, function, how it works and both advantage and disadvantage of the service provided in internet.

History of Internet

1969- Internet developed from an early USA government-funded "internetworking" project which called Advance Project Research Agency Network(APRANET). The purpose for this project is tend to connect the researchers which come from four universities in USA which are Stanford Research Institute, UCLA, UC Santa Barbara and University Utah.

1972 - Network Control Protocol is announced to allow computers working on the same net to communicate with each other.

1973 - Bob Kahn working from DAPRA Vinton Cerf from Stanford begin work developing TCP/IP to allow computers on different networks to communicate with each other.

1974 - Kahn and Cerf refer to the system as the Internet for the first time.

1976 - Ethernet is developed by Dr. Robert M. Metcalfe.

1976 – SATNET, a satellite program is developed to link the United States and Europe. Satellites are owned by a consortium of nations, therby expanding the reach of the Internet beyond the USA.

1976 – Elizabeth II, Queen of the United Kingdom, sends out an email on 26 March from the Royal Signals and Radar Establishment (RSRE) in Malvern.

1976 - AT& T Bell Labs develops UUCP and UNIX.

1979 - USENET, the first news group network is developed by Tom Truscott, Jim Ellis and Steve Bellovin.

1979 - IBM introduces BITNET to work on emails and listserv systems.

1980s-When other networks are connected to APRANET, the actual internet was borned. The word "internet" started to use in 1982. In 1986, the "freenet" is created in Case Western Reserved University.

1991-Business agencies was allowed by the USA government to connect to the internet.

Now-Everyone can connect to the internet since they have pucharse the internet access that provided by Internet Service Provider. People use internet to share information. communicate with each others and use the services hosted on internet.

Electronic Mail

Electronic mail (e-mail) is the conversation of computer-stored messages by telecommunication. Usually the e-mail messages are encoded in SCII (American Standard Code for Information Interchange) text. The e-mail also can send in non-text message such as graphic images and sound files. The e-mail is the most popular and was the first uses of internet. E-mail is one of the protocols included with the Transport Control Protocol/Internet Protocol (TCP/IP) set of protocols. A general protocol for sending e-mail is Simple Mail Transfer Protocol and a general protocol for accepting it is POP3.

SMTP(Simple Mail Transfer Protocol) is the protocol used for email on the Internet. The SMTP describes a message format and a process to path messages through the Internet from source to destination via email servers.

POP3(Post Office Protocol version 3)used by local e-mail clients. It is an application-layer Internet standard protocol, to save e-mail from a remote server over a TCP/IP construction. Almost all subscribers to specific Internet service provider e-mail accounts access their e-mail with client software that uses POP3.

MIME(Multipurpose Internet Mail Extensions)is a specification for configuring non-ASCII messages so that they can be sent over the Internet. MIME enables users to send and receive graphics, audio, and video files via the Internet mail system. In addition, MIME supports messages in character sets other than ASCII. There are many predefined MIME types, such as GIF graphics files and PostScript files. It is also possible to define your own MIME types. In addition to e-mail applications, Web browsers also support numerous MIME types. This allows the browser to show or output files which are not in HTML format.

How Electronic Mail Works

The email program (the client) sends the message off to an email server by using the SMTP(Simple Message Transfer Protoco)l. The email server is a program running on another computer which mostly located at ISP(Internet service provider).At the server, the message is divided and the recipients discarded from the message’s To, Cc, and Bcc fields in the header. The SMTP server then searchs the host computer for the recipients. For example, if the message is being sent to [email protected], the server looks up Hotmail.com and sends the message go to that computer. For a few seconds, the message trips around the Internet as it makes the connection to the endpoint computer. At the endpoint computer, another SMTP server brings the message and things it into a mailbox for the planned user. There, it stays and waits until the user logs in to read mail. But the mailbox on the server is different thing compare to the inbox in a PC’s mail program. The recipient’s mail program collects new messages from his ISP’s server. The mail program uses the POP(Post Office Protocol) to fetch the message. POP is used instead of SMTP because the email message is no longer being sent on the Internet; it has attained. All the POP does is bring the message waiting on the server and transmission it back to the user’s computer and his email program. The mail message is stored in a database after it is on the recipient’s computer. Covertly, all email programs are basically a database program. The messages are exist in several mailboxes organized by email program which are Inbox, Deleted Items, and Junk after they are received.

When a user want to send an email, they create an email in their MUA(Mail User Agent) which is an application used to read and compose email, and sends it.

The sender's MUA transfers the email to a Mail Delivery Agent (MDA). Commonly, the sender's MTA also handles the responsibilities of an MDA. Several of the most common MTAs do this, including send mail and mail queue. The MDA or MTA routes it to local in-boxes or frontwards it if it is not nearby addressed after it accept the email. In diagram, the email forwards from MDA to an MTA and it enters the first of a series of "network clouds," labeled as a "Company Network" cloud.

An email can encounter the largest network cloud in which called as Internet or network cloud within a large company or ISP. Most of the email service providers and other companies have their own private network clouds that used to process a large volume of email. These organizations normally have numerous mail servers, and route all email through a central gateway server that reallocates mail to whichever MTA is available. Email on these minor MTAs must usually wait for the primary MTA (i.e., the designated host for that domain) to become available, at which time the minor mail server will transfer its messages to the primary MTA.

The email in the diagram is addressed to someone at another company, so it enters an email queue with other outward email messages. If there is a high volume of mail in the queue, either because there are many messages or the messages are abnormally huge, or the message will be postponed in the queue until the MTA processes the messages forward of it.

The email enters the Internet network cloud, where it is transmitted along a host-to-host chain of servers as it clears the queue. Each MTA in the Internet network cloud needs to "stop and ask directions" from the Domain Name System (DNS) in order to identify the next MTA in the delivery chain. The particular route be determined by partially on server availability and typically on which MTA can be found to accept email for the domain identified in the address. A pair of messages creating from the same host and addressed to the same receiving host could take different paths because most of the email takes a path that is dependent on server accessibility.

Before the email is received by the receiver, it is tested by the firewall to prevent virus and spammer. Afterwards, the email is accepted for delivery by the receiver's MTA. The MTA calls a local MDA to deliver the mail to the correct mailbox, where it will sit until it is retrieved by the recipient's MUA.

Internet Relay Chat

IRC(Internet Relay Chat) is a chat system which developed by Jarkko Oikarinen in 1980s. IRC has become very popular due to more people get connected to the Internet because it enables people connected anywhere on the Internet to join in live discussions. For those who wants to join an IRC discussion, they need an IRC client(a program that runs on your computer and sends and receives messages to and from an IRC server) and internet access. The responsible of IRC client is making sure that all messages are broadcast to everyone whose partaking in a discussion.People can exchange text messages interactively with other people all over the world by using an IRC client. An IRC user is required to download a client to allow them to log onto these servers. After connected to the server, the user can join any channel and converse with others there. That could be private or public, between one or more people for the conversation in IRC. The information can traded in any form which similar to the e-mail attachment due to the IP address of user can be made known. There are few popular IRC client examples which are mIRC, Pirch, and Virc for Windows and Homer or Ircle for Mac's.

Common Attack In IRC

There are few type of attack that can be seen easily in IRC which is Trojan horses(program in which spiteful or harmful code is contained inside apparently harmless programming or data in such a way that it can get control and do its chosen form of damage, such as corrupting the file distribution table on computer’s hard disk), running unknown scripts(Channels usually auto-offer scripts to ease IRC use and it may contain trojans) and websites refferals(Websites advertised on channels which may utilize the victim’s computer for other malicious purposes).

To avoid these attack, an IRC user should check before download anything, do not accept anything from stangers, do not run any unknown scripts and update virus definition time by time. As recommendation, user are suggested to install an anti-virus software in their computer to protect their computer from these common attack.

News Group

Newsgroups was first created in North Carolina back in 1979. That is when a couple of Duke University students bent a few computers together to start an exchange of information with other UNIX users. Just down the road at the University of North Carolina in Chapel Hill, another student was writing software that could be used to allocate the information. Eventually, the work of these three students became the first bastion of newsgroups, termed Usenet. A news group is an online discussion group which is similar with forum. There are accurately thousands of newsgroups covering every likely attention on the internet. It require a news reader which is a program that run on computer and connects to news server on the internet to view and post messages to a newsgroup. A news group is a web-based discussion about particular topic. The range of the topic for news group is from sports, cars, investing, teen problems, education. The construction of newsgroups is comparable with the e-mail. The news and articles of newsgroup are stored on a central server with thousands of clients downloading the article. The server would also store running conversations about a certain article which users are able to subscribe to.

By using NNTP, connects to the news server selected in your configuration. Usually, the news server's connection information is provided by subscribing to Usenet service. The newsreader will downloads all of the new messages posted in the newsgroups that you are subscribed to once the connection is recognized. You read through the messages and decide to answer to a post. You also decide to start a new thread with a post of your own.

Critical comments and analysis

The internet can be defined as one of the greatness invention in the world. The internet connects everyone in every part of the world. Internet brings a lot of benefits to people, it allows people to communicate with each other’s even they are in the different place. Even the internet brings some harm, cases such as cyber bully and cyber-crime happens frequently. The complicated technology created just for the simple purpose. But the internet still brings more good compare with harms. The users of the internet should be use the internet properly.

Conclusion

In conclusion, internet allows people to communicate and share information with each other. People may use electronic mail, internet relay chat and newsgroup to share information time by time. The technology allow people to communicate with each other easily even in the different place, anytime. People should appreciate and use this technology properly.