Email Attachments, What’s The Big Deal?

In the earliest days of messaging between remotely connected computers, email was purely a text based (7bit) system. At the time each character sent was considered an expense. An expense not only because of the hideous cost of very low bandwidth across any distance but also because of the limited bandwidth. So, we should remember that the email system, from the outset, was not designed to handle file transfers i.e. ‘file attachments’ or ‘mail attachments’.

As is their nature, techies will be techies and they soon figured out a way to attach files to emails with what are, essentially, add ons or extensions to the original email program. Undoubtedly, this development launched email as the ‘go to’ way of communicating in our emerging modern age. Indeed, email remains the killer app when it comes to messaging applications.

Now, we should take stock and remember that as fantastic as this development was, it happened at a time when even dial up Internet connections were a rarity. As the techies gathered in bigger numbers to develop bigger and bigger ideas resulting in faster and faster Internet speeds, people started attaching bigger and bigger and BIGGER files. Latest blockbuster movie attached to an email and sent to a mailing list anyone?

Well, why not? Why can’t we send the entire Brittanica Encyclopaedia attached to an email? In the misty beginnings of the Internet, when we Internet users where as thin on the ground as fast Internet links, it was little more than an irritation to some network techs wondering why their switches were clogged up occasionally.  But now? Okay, let’s break it down into a neatly bulleted list of “why nots?”

  • Every email represents a chunk of data that has to be delivered via email servers. The bigger the chunks and the more of them, the more computing power you need to process (scan the email body for bad links, unpack the attachments scan them for SPAM, viruses and malware, pack them up again, reject or send them on the way) all those chunks of message data. Here’s that word ‘expense’ again and the costs have to be passed on somewhere. Even with the immense resources available to Google, Gmail only allows 25MB attachments. So why not? Well, your internet would be more expensive and slower.
  • The email and its attachment you send may have to pass through several mail servers (in this case called mail exchangers or MX for short). Each of these mail servers may be configured to accept different sizes of mail. So whilst your own ISP’s server might allow 5MB for mail sizes the next mail exchanger may be configured only to allow 3MB and will bounce the email. So why not? Your email may not arrive at the destination causing, at the very least, frustration..
  • Etiquette. This may be the all important item on this little list. Given that the likes of OPQ’s most detested adversaries, SPAMMERS, probably heard of etiquette, let alone practice that simple, but so inexpensive art. To clarify; how would you like spammers to have to ability to send you movie size files? Oh, imagine the malware…  the damage! So why not? Really why not? Have some MANNERS and don’t clog up our inboxes!

“Okay, okay,” we hear you cry, “what should we do? What can we do?”

These size limitations can easily be exceeded as they are calculated not on the original size of the email and any attachments, but the MIME -encoded copy. The encoding can bump the total email size to be processed up to about 37% of the original file size.

OPQ limit the allowed total email size to approximately 10MB which means our configuration allows for total email sizes of just over 14MB. Note OPQ’s rules for attachment sizes are global, meaning they cannot be changed on a per domain basis.

Fortunately for us, those tireless techies have been beavering away inventing new ways of sharing large files via email. Probably the most popular and well supported by pretty all email applications is Dropbox.

With Dropbox integrated into your email application, instead of sending the attachments with the email, your email will include a link to Dropbox for you recipient to download the files from Dropbox’s cloud service. It should be noted that currently Dropbox does not support end-to-end encryption.

This type of solution offers convenience for senders and recipients of an email with ‘attachments’. As well as a workaround for the limitations of sending large files, the solution reduces the work load on internet mail servers making for a more effective and efficient delivery system.

There are, of course, many other popular products that offer the same or similar solutions. Google Drive with its 15GB free storage for example. See here for other solutions that offer better security via end to end encryption, bigger free storage and more. 

Hopefully this article has gone some way to explain the reasons for size limitations when it comes to email attachments and offered some simple solutions for ways around the limits.

How do you manage your large email attachments? Let us know in the comment section below.

Comments

  1. Niaz June 24, 2019 at 12:04 pm

    Very well written article. Suggest ammending the Google Drive limit of 15Mb to 15Gb.

    • OPQsysAdmin June 25, 2019 at 8:47 am

      Thanks Niaz,

      Always appreciate your comments and assistance.

      Updating the article shortly, well spotted!

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