Understanding Email

Email is used almost universally today by everyone, and has been around now for five decades. However, in arranging an email service many far too technical terms are often bandied about by the practitioners. This article sets out to demystify the jargon, and to assist you in choosing and configuring an appropriate email platform and options for your business.

Demystifying Email Protocol Jargon



The Post Office Protocol, now in it’s third version POP3, has been with us for around 30 years, and while extremely basic, is still in widespread use.

Imagine a physical Post Office box that you might subscribe to. Periodically a postman will put messages into your mailbox, and periodically you will open the box to get your mails. Once you take them out the box is empty. If you don’t take them out often enough, the box might fill up and there would then be no more room until you emptied it. This is exactly how POP3 email works.

Note there is nothing about sent items, or other folders to manage – all these exist only on the device you use to open your mailbox.

If you use multiple devices to access mail – who does not these days? – you will only be able to get your inbound emails on the first device that opens the mailbox… EXCEPT.. there is a small benefit in POP3 over a physical box that allows you to leave a copy on server  for your other devices to read too.

If you use POP3, you must ensure you have a good local backup solution in place – if you lose your device, or it fails, your emails are lost forever without it.


The Internet Message Access Protocol was introduced in the mid ’80s to avoid the limitations of earlier POP3 protocol, with the current version (4) being standardised in the mid ’90s. Instead of just a simple inbox, IMAP allows a user to create folders on the mailbox server for storage and categorising emails, plus an offline mode where a local copy of all the server folders is cached for offline access, and is synchronised with the online copy when connected.

So not having a local backup is no longer critical, as all messages are always stored on the server. Multi-device access is also no longer a problem, as each device in use can synchronise their local copy.

Additionally, if you choose to store your Sent Items  on the mailbox server also, each of your devices can also then access all emails sent as well.

As most providers, including Gmail, support both IMAP and POP3, we recommend using IMAP over POP3 almost always. The only value in POP3 these days is with automated attendant services responding to email requests. For example, you may have a ticketing system that needs to read inbound emails and assign them to some function – an ideal scenario for POP3.


Pioneered by Microsoft in their Exchange email server, and now with Office365, Activesync is a far more complex form of IMAP, and allows all sorts of other types of data, such as contacts, calendar, tasks – plus Sent Items – to be synchronised with the mail server. Collaboration is also provided for with the ability to share mailbox folders, and includes a complete Public Folder infrastructure for sharing items organisation-wide.


Regardless of which of the above protocols you use to access emails, all emails between different email servers use the Simple Mail Transfer Protocol Even if you use IMAP/POP3 for access, you must use SMTP to send mail. Activesync is the only exception as it synchronises both inbound and outbound emails with the server. SMTP was introduced in 1982, and enhanced in 2008 (ESMTP) – essentially identical, but more efficient.


While this term is not heard so much currently, it is in constant usage every day behind the scenes. The SMTP protocol, for historical reasons, transmits data using only 7-bit ASCII code. This means that it can only send alphanumeric characters – text and numbers. Graphics, fancy fonts, etc were not under consideration when SMTP was developed – only the ability to send textual data was ever envisaged. Due to transmission bandwidth limitations, send only 7 bits (as apposed to 8 bits) was far more efficient.

Fast-forward 15 years – to when we started wanting our emails to look prettier, and we also wanted to add attachments. No-one wanted to start again, as SMTP worked so well, and was so widely used, so Multi-purpose Internet Mail Extensions were introduced to re-code all content into 7-bit ASCII when sending, and to decode back into native format when received. Every mail client application today uses this translation technology automatically.

Planning your Email Deployment

Now that we have clarified the jargon of email access, we need to introduce yet another set of terms that are in widespread usage, and help us to set up our email systems to our best advantage.


Each user is assigned a mailbox, which has at least one email address attached to it. This email address is also used. along with a password, to authenticate the user attempting to access the mailbox. This credential is thus your mailbox key.


A user might have one or more aliases. For example, Cassius Clay changed his name to Muhammad Ali. What if some of his correspondents did not know he changed his name? His email address might now be muhammad.ali@company.com, but he still wants people to be able to send him emails via cassius.clay@company.com – so we create an alias. He might also want to be addressed as thechamp@company.com – no problem, we create another alias.

Distribution List

Consider that you might have a regular need to send an email to all your staff – perhaps a company policy update. If you have five staff, you just need to remember add each address in the TO: line of your email. But what if you have 5000 staff?

The solution is to create distribution list. You might call it staff@company.com, and add all staff emails addresses, and update as staff changes. You might also have a team of 20 sales people, and have a contact link on your website – which you want all sales staff to see. You might have a team of zero sales people, but this does not stop you creating such a Distribution List regardless. The solution for both is a Distribution List sales@company.com.

As you can see, distribution lists provide very much needed functionality. Instead of creating a mailbox for info@company.com, instead consider creating a Distribution List, and adding the appropriate people to the list.

When an email addressed to a Distribution List arrives, the email server simply copies the message into each user’s mailbox on the Distribution List.

Distribution Lists and Aliases are typically not charged, but every additional mailbox will always incur a charge.

Another popular use for Distribution Lists and aliases are for when a staff-member leaves the organisation. While you may not wish to advertise this fact, and still want to be able to receive emails inbound, the solution is NOT to have someone log into the departed user’s mailbox, but to convert it to an Alias or Distribution List and thus have it forwarded automatically to the replacement staff member. Of course you also need to decide whether the old emails for the departed staff member need to be retained or deleted permanently, but you needn’t pay for unnecessary licenses for an unused mailbox.


Anyone who uses email is constantly bombarded by unsolicited, junk, undesired emails – a spammer can sends 1000’s of email for a fraction of a cent – and dealing with these is a never-ending problem. For more information on how to protect your mailbox, as well as ensure that messages you send are not ‘junked’ or blocked by the recipient, please view our in-depth article on this subject.

Regardless of your email needs, PASR understands email and has a solution to meet them, and we welcome your enquires as to the best solution for your enterprise.

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