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You know that email is the most used application on the internet, in fact, most of us depend on it. Would it surprise you to know that email technology is actually very simple to understand, and that understanding can save you a lot of frustration?

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We are covering email this time: how it works and why it sometimes...well...doesn't. We also talk about Grandma and Nephew and I share with you one of the key laws of technology - made public for the very first time.

Get yourself a cup of coffee (or beverage of choice) and take a 10 minute break as we explore the issues around one of the most important software applications today. I will try to make it 10 minutes well spent, but if not, hey, you need a break anyway don't you? :-)

When people think of the Internet, they mostly mean the web. You know, browsing web sites like Google, Microsoft, News24, Yahoo, online papers, hobby sites, etc, etc.

Yet, the most used services on the internet are not web sites - humble, boring old email is.

As an ISP we know this VERY well: if you mess with someone's email service, you better have a double latch on your door, or a very good medical aid!

People depend on their email service for customer support, orders, sales, enquiries, keeping in touch with friends and family and, occasionally, to accidentally install a new virus on their computers. (By the way, if you want to learn how to protect yourself from spam and email viruses, see this article).

If their email breaks, people tend to get very cranky very quickly! Some are even prone to violent behavior and very explicit language.

While email malfunctions can mostly be avoided, everyone has to set up an email account for the first time. This can turn out to be an experience that severely taxes their patience - even more so if the poor technical guy mention terms like SMTP and POP3 and ports and stuff. Even an innocent question like "so what is your password?" can get you nominated for the smart-ass-of-the-month award in two seconds flat.

The worst bit is when they install some virus scanner (like Norton for instance) and their email breaks completely or becomes very slow - even the dog better find a very good spot to hide until the smoke clears.

Know the enemy

I have a general theory (law) about computer technology: I call it "The crouching-machine-hidden-pain" theory, and it goes like this:

The risk of you putting your fist through your computer's screen is directly inverse to how much you know about the technology.

For example, if you knew how CRT monitors work, you would not try to put your fist through it, because you know you will break every single bone in your hand. This will invariably lead to you screaming profanities at the top of your voice while hopping around clutching your broken hand. You might even cry a little bit.

Quite unbecoming.

It should be clear therefore that a basic understanding of technology is a) good for your health and, b) safer for your computer, and c) ensures your good name is not tarnished by "sissy" rumors. It should also be painfully clear also that your hand is not a suitable tool for breaking 3cm of reinforced glass.

Much of the suffering, aggression, law suits and embarrassing moments can be avoided if we see the crouching-machine before it pulls the infamous hit-your-hand-with-reinforced-glass trick. Translated: if we understand how email works, we use use baseball bats instead of fists.

Sorry, I'm getting carried away. I mean, to understand email technology enables us to use it better - with less pain. :-)

So let's take out some insurance against unnecessary pain by understanding the concepts that make email work:

It's not so different after all

In concept, email works in very much the same way as normal postal mail - except that it normally arrives at it's destination.

A quick example:

Let's say you have a private post box at your local post office. Every so often you would jump in your car, drive down to the post office, unlock your private box and retrieve your mail.

You take your mail back home with you, throw away the junk mail and read the rest - leaving the envelope from SARS for last, until after you had a valium or two. Some of the letters require a response or (worse) a cheque to be mailed, so you write a cheque or two and stuff them into envelopes and put them in a neat little pile to take with you when you go to the post office again.

The next day or so you drive down to the post office again and place your outgoing mail into a special post box (the big red one dogs like so much), walk over your own private box, unlock it and check for new mail.

The online version

Email works in very much the same way. Of course you don't have to drive your car, there is no physical post box, your email actually arrives at it's destination, no dogs surf the net, and you get a lot more junk mail, but bear with me: it's almost the same.;)

Instead of driving your car to the post office, your plop down in front of your computer and start Outlook (or similar email software).

The software now uses your computer's internet connection to contact your post office - called a POP3 server. (Post Office Protocol version 3, but more about that later). Of course you told Outlook previously where your POP3 server is because the internet is a big place with many thousands of email servers.

So, let's say your POP3 server is called mail.cozahost.com. Name servers on the internet will translate this name into an IP number (the address of a server) and open port 110 to talk to it.

In our real world analogy this would be like giving a driver the address of the post office and instructing him to use a specific route.

This is important, because you won't be able to find your mailbox (and email) if you rock up at the wrong post office. Duh.

The POP3 server will now receive a request from your Outlook to open your mailbox. Since we don't want other people to read our email, the POP3 server will ask Outlook for a password (like a key) before it will allow access to the mailbox.

Once the POP3 server is satisfied that you are who you say you are, it will allow you to download your email.

When everything works it is pretty simple right? (We will cover things that go wrong later)

Sending email is different

Just like you cannot post outgoing mail to your private post office box (but use the big red one instead), email also requires you to use another kind of server to send email. These servers are known as SMTP servers. (Simple Mail Transport Protocol)

POP3 servers are simple. Their only function is to store email received from SMTP servers in mailboxes where users can retrieve them. The real work is done by SMTP servers.

Let's make a quick detour to the real world again to equate that with email:

After you mailed your somewhat elastic cheque in that big-red-dog-magnet, a postal employee retrieve it - eventually - to take to the sorting room for forwarding to the next post office. For example, if your letter has to go to Sandton from Clifton, then your letter will be sent to the Cape Town post office, then to Johannesburg and then to Sandton.

Contrary to popular belief this piecemeal, one-jump-at-a-time way to deliver mail was not designed to create jobs. It is simply more efficient to first collect all the mail that must go to Johannesburg and then send them in one batch.

In the old days SMTP servers worked in the same way. SMTP servers forwarded email by jumping from one server to another. This was necessary to avoid long distance phone calls. For instance, a server would forward email from Clifton to Cape Town, to Bellville, to Paarl, etc - until it reached Johannesburg in a number of jumps. This process of passing on email to the next closer server is called "Relaying".

Today of course, the internet is one big place. Whether you send email to Japan or Buffelsfontein - it's the same thing, so you don't really need to relay anymore - email is just transferred directly to the destination in one go. The problem is that hundreds of thousands of servers use the SMTP protocol (ie store and forward). Changing to a new protocol at this stage is not something that can be done easily. (These relays are a major cause of spam. See this article on why ISPs struggle to block spam)

Let's get practical

Up to now I've just said "email" as if it is something you can touch. It's not. Let's look deeper under the bonnet:

An email - and that is ALL email - is actually a text file. A normal, standard, house variety computer file. These files use a simple structure that basically says:

"I was sent by youremail@home.com with the subject "I love newsletters" and it should be delivered to grandma@farfromhome.com. This message originated at mailserver.home.com and it was submitted at 12h01 on Friday 13-Feb-2005"; and a few other odds and ends to help the SMTP servers track what is going on.

SMTP servers understand these files. They open the file, notice that it must go to someone at the domain farfromhome.com. Now they ask internet name servers to give them a list of email servers that is willing to accept email for recipients in the farfromhome.com domain.

The list of mail servers for farfromhome.com is prioritized, so our local mail server contacts the first one on the list. If it can contact the first, preferred server, then it asks the server to take receipt of an email file for grandma. The farfromhome.com server checks it's address book, sees that it knows someone called grandma, and it says: "Sure, pass it on dude."

The email file is now transferred to the farfromhome.com server and handed over to the POP3 server so that grandma can read your not-so-subtle-hint to send money - quick.

The annoying nephew

Of course things don't always go perfectly, as all of us using computers on a regular basis know only too well.

If, for some reason, the mail server for home.com cannot contact any of the servers for farfromhome.com, then the local server will wait for a few minutes (normally 10 or so) before it tries again.

If it fails the second time, it will wait another 20 minutes or so, and keep on retrying for up to 24 hours.

Thoroughly exhausted from trying to deliver your email for a full day without success, the SMTP server for home.com returns the email to your POP3 server with a not so subtle note telling you that, despite it's best efforts, the servers for farfromhome.com simply did not answer any calls and it could not transfer the email file.

Meanwhile, back at grandma's ranch, this is what happened: The mail servers for farfromhome.com actually WERE at home and heard the server from home.com knocking at the door. Before they allowed a connection (opened the door), they ran a quick check on a RTBL (Real Time Block List). This list told them that grandma complained that the home.com mail server is used by an annoying nephew to solicit money...in other words, it is spam.

Convinced that the home.com server is a spammer, the farfromhome.com server ignores the connection request. Thing is, if farfromhome.com opens the door (in a manner of speaking) to tell the nephew to go away, then the spamming nephew may try some other means to bother grandma. Like annoying uninvited relatives who insist on visiting at the worst possible time. You know what I mean. So farfromhome.com ignores the request to connect - pretending not to be home as it were.

Of course nephew will now contact his ISP to complain that home.com does not deliver email to farfromhome.com, and insist on having it fixed...immediately, if not two seconds sooner.

But wait, that is not all:

Sometimes you get even more street wise grandma's - they change their email addresses.

Instead of the usual grandma@farfromhome.com email address, they change to hotchick@farfromhome.com.

When Nephew's email arrives, the farfromhome server sends it right back, because there is no such person as grandma@farfromhome.com. (Crafty old girl!)

The dark side

Some (most) grandmothers however, love to hear from their nephews and grandchildren, and they don't list their nephews as a spammers or change their email addresses - but yet your email is not delivered.

Instead of calling grandma a crafty old scrooge and/or screaming obscenities at your ISP when your email is returned as undeliverable, you should be aware that there might be other, darker and more sinister factors at play:

The MAJORITY (that's right the majority) of email traffic on the internet is spam. This means that servers and networks are constantly bombarded with millions upon millions of junk messages. In many cases either your own server is too busy processing the latest offers for "that-blue-pill" or grandma's server is playing hide and seek with other servers offering "enlargement services" to accept your email. In both cases, some scumbag bought 94 million email addresses from a spam vendor and is happily sending each and every one of his "potential clients" an "offer".

As if professional spammers weren't enough to frustrate us, millions of internet users cannot be bothered to keep their operating systems up to date with security patches. Inevitably this leads to an email surfacing every once in a while resulting in BILLIONS of messages being sent around the internet as more and more PCs are infected. Once again, either your or grandma's server may be so busy coping with the junk that your email simply cannot be delivered - because your well written solicitation for a few rand "loan" is number fifteen million nine hundred thousand and thirty four in the queue.

In the final case, if grandma's SMTP servers are actually coping with the dual onslaught of spam and viruses, her ISP might have some problem (there are depressingly many) with it's server or network - effectively taking the servers offline and thus making your email undeliverable.

(Increasingly, spam and virus filters on grandma's PC, her ISP's server or your own PC will delete email because it (mistakenly) believes that it is spam or a virus. In these instances email can disappear completely and without a trace. Very nasty, and increasingly common.)

Considering all the problems on the internet today, I'm amazed that 99.9999% of legitimate email actually gets delivered successfully!

The weakest link

Understanding that there are several links involved in the email chain will help to understand that an undeliverable email is not necessarily your or your ISP's fault.

The best course of action is therefore to take a few deep breaths (or a chemical of your preference) and eliminate the usual suspects one by one to ensure that you do not waste energy (and anger) on the wrong party. After all, the guilty one deserves the full, undiluted force of your wrath, not so?

Simple practical steps

Here are the simple steps you can use to pin-point any mail related problems:

Test the 3 main components involved in a typical email "conversation":

1. Your PC and internet connection

• Test your connection to the internet by visiting a web site - for instance the web-based email provided by your ISP.
• If you have firewall or virus scanner software on your PC, TEMPORARILY disable it to see whether or not it is causing the problem.
• Make sure you are using the correct names for your POP3 and SMTP servers as supplied by your ISP.
• Test your outgoing and incoming email by sending email to someone you know does not exist, eg: no_one_there_007 @ ibm.com. If your email reaches the IBM server, it will send it back to you as undeliverable: this verifies that your email reached that server (ie the send was successful) and was returned (ie the receive was successful)
• Read the error message!!! Simple: when something is wrong, your computer will try to tell you what it is. Ignoring the message is not a clever way to fix the problem.
• Use a step by step guide to make sure your email software is configured correctly, like this one by Cozahost...
• Most SMTP servers require you to authenticate before you send email - make sure you switched this option on. (see the guide above)

2. Your ISPs POP3 and SMTP servers

• Login to your web email to send and receive email. If it works, you know that the problem is not on the mail servers, but on your own PC.

3. The destination SMTP server.

• Grandma's server may be offline or simply ignoring you. Try to send email to someone at another domain. If it arrives, then you know the problem lies with Grandma's ISP.

Cheque is in the mail

If someone say that they sent you email, but you never received it, send them a simple "please reply" message to which they must send a reply with a simple "Yes, I received it".

This will verify that the two SMTP servers can talk to one another, that all the email addresses are valid (ie a missspelling did not slip in) and that the content of the message (ie a zip file, words that trigger spam filters, etc) did not cause the message to be zapped by an over zealous filter.

In closing

Now that you have a basic understanding of how email works, I hope you will find it a little easier to cope with the inevitable frustration when things do not go exactly as planned.

You now know how to spot the crouching-machine and duck the hidden-pain. Go in peace Fearless One.

At Cozahost we help small companies and professionals tame the internet so that they can concentrate on making money. We take care of the technical stuff so that they can take care of business. Here are some of our products and services:

A lady was walking down the street to work and she saw a parrot on a perch in front of a pet store.

Without warning the bird suddenly spoke: "Hey lady, you're really ugly."

Well, the indignation of it all; insulted by a few ounces of green bird! Storming past the store the lady continues to her work.

On the way home she saw the same parrot: "Hey lady, you're really ugly."

Not certain she could stand much more, the lady nonetheless restrained herself and went about her business.

The next day the same parrot was on the job: "Hey lady, you're really ugly."

This time there was no turning back. The lady enters the store and confronts the owner. Amidst threats of suits and other dire happenings the fellow protests and says that parrots don't really understand what they're saying but to no avail. Finally he apologizes profusely and promises to make sure the parrot didn't say it again.

When the lady walked past the store that day after work the parrot called to her,

"Hey lady."

She paused and said," Yes?"

The bird replies,

"You know."
 

Thanks for reading this newsletter and we hope you enjoyed it! Please contact us if you have comments, suggestions or questions - we would love to hear from you!