VITTA Networking CD - Why network?

networking curriculum
support CD for senior
secondary studies

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networking > why set up a network? > email

Communications

Email

A network enables email - electronic mail. Email can be sent and received at any time or place, unlike telephone calls and public-address announcements which have to be handled immediately and can often interrupt more important business.

It is such a simple idea: sending mail electronically. But it proved to be a "killer application" - a program that made millions of people connect to the Internet just to get it. You can send a message to one person or many people in one operation. You can attach pictures, documents, files etc. to the email and they are also delivered. You can store the email addresses of correspondents in an address book so you don't have to remember or type in their address. You can automatically attach a 'sig' or signature to outgoing emails. Sigs typically contain your name, organisation, web links and other information you want to repeat in every email you send.

There's nothing very complicated about email. In a dedicated email program - or one built into your web browser - you type a message, perhaps attach a file or picture and send it to anyone else on the Internet.

The email client (the program that works for you to send and receive email) acts like a word processor when you're typing, and when you want to send the message, it delivers the message (and attachments) to the email address (es) you have chosen. SMTP (Simple Mail Transfer Protocol) is used to deliver email and POP3 (Post Office Protocol) is used to receive email from your email box.

Email gives the sender and recipient the luxury of thinking about what they are saying, and editing their words before they are sent. Since email is stored, no notes need be taken during phone calls, and old correspondence can be searched and printed. Team workers can easily share documents by attaching them to emails and sending them instantly anywhere in the world.

Benefits of email

Organisations and individuals can benefit greatly from having email either across their network, or over the Internet. Colleagues can instantly send memos, messages, documents, web links, pictures, programs and requests to other each other, whether they are in the same room or halfway across the world. Since email is often delivered instantly, responses can be given immediately and work productivity is greatly improved.

Since email is electronic, the amount of paper used and wasted is also greatly reduced. Emails can be stored forever for later reference, and can be searched for particular information.

For individuals and families, email is an excellent way to keep in touch. Parents can keep in contact with children travelling in nearly any part of the world; widely separated people can get in touch with each other quickly and easily.

Using a mailing list, which is simply a list of email addresses with a group name, individuals can spread a message to many people at once, which is an efficient way of communicating with work teams or family members.

Telecommuters - people who work at home - can easily send work or information to their organisation regardless of where it is, any time of day or night.

Email could be compared to the invention of the postage stamp in the 1840's which boosted postal services and therefore communications across great distances. The immense complexity of the Internet requires the efficient use of resources to quickly deliver services. These services can take many forms, such as web browsing and file downloading. Email is no different and requires identification at each person's point of mail delivery.

What makes the Internet so interesting is the recipient of email can access mail boxes that are not tied to their physical location. The mail box for anyone can be located on servers anywhere in the world, and can be read from anywhere in the world. All that is required is the user's identification of the username and password.

The other main benefit of email addresses was to make them reasonably easy to distribute to potential correspondents. The URL system and email addresses are closely related. Given that the email services are provided by Internet servers the address of the server contributes to the address. The domain name of the server is combined with the user's logon name, for example:

billsmith@hotmail.com

The @ sign is used to split the username from the domain name.

Drawbacks

One drawback of email is spam: unsolicited email. Spam is a growing problem as the mass of unwanted mail clogs up mail servers and users' email boxes, and wastes workers' time.

Electronic junk mail, messages from people you don't know, about topics you didn't want to know about! Sometimes the topics are hair raising and unpleasant. Why do you get this stuff? What can you do about it?

Unsolicited email is now the biggest source of computer viruses.

If you ever give your email address to anyone, especially responding to web pages, it could end up being used by a spammer. Carefully read the privacy statements of any website you give your email address to. Some organisations sell email addresses to spammers.

Sometimes, spammers don't even bother using known email addresses - they randomly send emails to randomly generated addresses, hoping that the email arrives at a real emailbox. The cost of sending email is so small, spammers can easily afford to send a million emails if only one sucker sends them money in return. Even just opening an email from a Spammer to look at the pictures in it can confirm to a Spammer the email has ended up at a valid email address and the mail has been read. It will do not harm to your machine, but will guarantee you will receive email for much longer to come.

Don't put your real email address in any web page or newsgroup (Usenet) message. "Munge" it - distort it - so humans can work out the real address, but unintelligent spammer software cannot e.g. msmith@mySPAMdomain.com.

The real problem with spam is the vast amount of time and bandwidth it wastes. You can use filters in your email program to detect and delete spam, but you still have to download the email first, which costs you money and time.

For example, on an average day a worker receives about 200 emails - and only ten of them are real mail. She uses email filters, SpamCop and Spam Assassin software to evaluate each email and judge whether it's likely to be spam based on where it came from or what it contained. Still, she has to download each email before she can test whether it's worth keeping or not. The danger is, if she sets her filters too strictly valid emails could be deleted before she's seen them. If she had a filter to delete all emails containing the word "Mortgage" (a typical spammer word), she could end up deleting emails from her home loan company telling her that she was behind in her payments!

Spam is reaching "critical mass" - in other words, it's about to explode. Some people think spam will destroy email entirely. In governments around the world, laws are being debated to control spam. New intelligent tools are being devised to detect and eliminate spam.

Maybe, a few years from now, we'll look back to 2003 and remember the bad old days, when - like in the old west when blokes in black hats wore guns and shot down the good guys - spam was a menace to society. Maybe spam will become such a flood that people give up and refuse to use email because it's not worth the time, cost, danger and trouble.

It would be a shame if email died. It is an immediate and powerful form of communication that many people rely on for business and personal reasons.

LINK: http://www.caube.org.au/spamstats.html

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