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Technically Speaking by Stuart Pearson

Created: 18/04/2012

Technically Speaking by Stuart Pearson

This month Stuart Pearson looks at email: how it works, how to set up your own email account, and different aspects of sending and receiving messages.

Electronic Mail:


The rise of electronic mail to the most widely used form of digital communication, especially in the business world, has been quite rapid. The predecessor to email, standard postal mail, now dubbed ‘snail mail’, has seen a rapid decline. This is due to the fact that email is perceived to be free and it is this perception that allows us to send information little and often – a method that would never be employed if we had to pay the price of a first or second class stamp for every email sent; we would simply send one larger message through.

With that in mind it can be seen how email has become a must-have form of communication in the digital age; in fact email is a requirement to sign up to most social networking sites. Internet Service Providers (ISP) will usually allow you to create an email address and use their servers, there are also a number of companies out there who provide email for you to use. They mostly offer the same service but some will offer virus scanning and spam filtering on the server side, which is good as it means that anything malicious can be prevented from ever entering your computer. However, this service should never be the only form of internet protection used and should be used along with your local anti-malware software as a belts and braces form of protection.

Once you have found the right ISP for you, it then comes down to choosing an email address. Different providers will have different rules as to which part of the address can be altered, it is usually anything prior to the ‘@’ sign. Some providers will also allow you to change the first word after the ‘@’ sign as well. Although it is possible in some cases to include a space in your email address it is best to avoid using one as there are providers, hotmail being one, which will not allow mail to be sent to an email address containing a space. It is best to stick to alpha-numeric values and hyphens ‘-’ or underscores ‘_’ as word separators. The second part of the address is usually made up of the domain name of the provider, for example Hotmail.com. Domain names are purchased by companies and individuals to make it easier for them to be identified on the internet.

Every server on the internet has a unique address, for example 192.168.2.1, might be a hotmail email server. If you can imagine the number of these addresses, it would be very difficult for us to remember every address for every website we would like to visit. Domain names were created as a way of making things easy to remember, I would like to visit Microsoft’s website so it is much easier to remember http://www.microsoft.com than http://207.46.19.254, both addresses will take you to the same page. In the background when you type in www.microsoft.com in your browser, a request is sent to a Domain Name Server (DNS) asking it to give the numeric address for that domain.


Mail Servers

Once you have your mailbox setup on the server you will need to configure your email client. Configuration required will depend on your chosen mail clients, Windows clients will have Windows Live Mail, Windows Mail or Outlook Express depending on the version of Windows installed. Any Apple users will have the Mail
program on their computer/device. The details required to configure your client, be it on your computer, tablet PC or Smartphone will be the same and are as follows:

  • Username
  • Password
  • Display Name
  • Incoming Mail Server
  • Incoming Mail Type
  • Outgoing Mail Server
Username and password are those you entered when signing up for your email address, some mail providers require you to enter your full email address as your username ‘j.bloggs@hotmail.com’ whereas others may require just the portion prior to the ‘@’ sign ‘j.bloggs’. Display name is how your name is displayed in the recipient’s inbox and sent items on your client; if this is not entered it will default to your e-mail address.

The two most common types of incoming mail server are Post Office Protocol (POP) and Internet Message Access Protocol (IMAP). It is now the case that providers will support both types and it is the choice of the user when creating the mailbox that decides which type to use. The key difference is that by default POP will deliver mail to the mail client of the user and delete it from the mail server once confirmation of delivery has been received. IMAP clients retrieve messages from the server leaving them in place; therefore it is only when you delete the messages from your mail client that the deletion will be replicated to your mailbox.

If you use mail on a number of clients it is best to configure you mailbox for IMAP, therefore all clients will be synchronised to whatever is on the server. If you only ever use email on your computer use POP as that way you can be sure that your mailbox will never be full and you will always receive mail.

Mail is always sent using a Simple Mail Transfer Protocol (SMTP) server, SMTP utilises relaying to send messages. Most providers have now shored up security on their servers and will only allow messages to be relayed from users or other servers that they know about. Previously all SMTP servers would allow messages to be relayed from all other SMTP servers, this made it possible for malicious people to relay a message to make it look as if it was sent from another domain. This was part of the reason why most SMTP servers require Secure Password Authentication (SPA) prior to allowing a message to be sent.

Any messages sent from unknown sources or messages to unknown addresses will now be rejected by the SMTP server, this is known as bouncing, as the message is ‘bounced’ back to where it originates.


Mail Format

An email is split into two distinct parts, the header and the body.
The header contains a number of fields and it is the client that determines which of these is displayed to the user. SMTP requires that the header contains at least the following fields:

  • To: The email address of the intended recipient.
  • Subject: A user entered subject for classifying the message, abbreviations are sometimes automatically added by the client such as RE: to signify a Reply and FW: for when the message has been forwarded.
  • Bcc: Blind Carbon Copy, entries in here will only allow the address of the current recipient to be shown. If you are sending a message to multiple people, but want to secure the identities/addresses of other recipients then use the BCC box.
  • Cc: Carbon copy, this is for when somebody is sent a copy of the message for information purposes or as an interested party to the message. Carbon Copies are usually displayed differently in a mail client.
  • Content-Type: Information about how the message is to be displayed, for example as plain text.
  • From: Who the message is from, it should be noted that this is not necessarily the sender of the message or the address that will be replied to when you click reply.
  • Precedence: commonly with values "bulk", "junk", or "list"; this is used to categorise mail for using automated responses or filing systems for messages. ISP’s that try to identify Junk mail often look to see how many recipients there are and change the Precedence to ‘junk’, this is the reason why some messages from people you know can end up in your Junk Mail folder.
  • Received: This will show a list of servers that have relayed the message before it got to your mailbox. This can be used for identifying the originator of a message.
  • References: A list of IDs linking messages together; this is used for creating the conversation view used in mail clients, otherwise known as ‘Threading’. If somebody clicks on the Reply button, this field is populated with the ID of the message it is in reply to. If the user then changes the subject and sets everything as if it were a new message, unfortunately in the Thread view messages will then appear out of synch.
  • Reply-To: If the message is sent on behalf of somebody else, it is possible to set the reply to field so that when a user clicks reply, an address other than the originators is populated. This is where people need to be careful as it is possible for malicious people to send a message looking like it came from one source and have the response sent to an entirely different address, this is usually used in phishing attacks, were the instigators are fishing for personal information.
  • Sender: This is the actual sender of the message, not necessarily who the message is from, if a secretary was sending mail on behalf of a manager then this would be populated with the secretary’s address.
  • Archived-At: If a mail has been archived, then this will contain the location of the archive.
The body of the email will contain the information, including links to any files, as you enter it. Also any signatures that you have created within your mail client will be included within the body of the message. This is the part that looks like a standard letter. Hopefully this will give a little bit more understanding as to how email works from you clicking the send button through to it landing in the recipient’s mailbox.

Following a spate of people being taken in by an intricate scam, details of the scam and how to avoid being taken in by it will be covered next month. If you have any questions or suggestions for future columns please feel free to get in touch.

Stuart Pearson

kelevra@blueyonder.co.uk

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