In the current age of online security, where everyone is talking about cyber crime, identity theft and the latest malware that can infiltrate the most secure networks on earth, the topic of spam sounds a little bit 20th century.

It is a problem that has been around since the dawn of the internet – and in the same way that most of us now receive less junk mail through the letterbox every morning, the fact that we see fewer spammy messages in out inboxes these days leads some to believe that it is a phenomenon that has largely been eradicated.

{photo credit: flickr}

The reality is completely the opposite, and if you want the evidence, try switching off your spam filters for a day and see what happens to your inbox. The truth is there is as much or more spam out there as ever – this global spam map shows the total volume of spam equates to almost 400 billion messages in a given day. Think about that number for a second – if every individual on earth was on email, that would be 50 spam emails each, just in one day!

So where are all these messages? The answer is that this tidal wave of spam is kept at bay by the sophisticated spam filters that we take for granted. Let’s see how they work.

Evolving technology

It would be foolish to believe that spam filtering is standing still. Like every aspect of online security, it is constantly evolving to remain effective and meet the changing demands of new technology. A case in point is the cloud. Many have heralded cloud tech as the biggest game changer of the past decade – but as well as bringing unprecedented convenience and flexibility, it also carries a new range of security challenges. A look at everycloudtech best reviewed cloud spam filter gives an indication of the innovative research and new technology being invested in this critical area.

At heart, the following three components are at the heart of cloud filtering.

1) Scanning header data

The header consists of far more than the sender name and the subject box. There is a string of other identifying data that accompanies every email, but that is not shown on the screen. It provides information on the IP address that sent the email, the server where it originated and the route the message took. The spam filter will check all of these factors, looking for anything suspicious. This might include something like a local IP address that come from an overseas server.

2) Blacklists

Every time your email flags a message as spam, the sender is added to a list. As you might imagine, there are plenty of these lists out there, and your spam filter will check out the most important ones.

3) Content

Finally, the filter will look at the content itself. Some things are obvious – if there is an executable file attachment or a link to a blacklisted website, the filter will throw it straight in the bin. Spotting spam from keyword analysis is more complex, and this is where filters can fall down.

Yet it is also the area that has the most potential for future development, thanks to the latest innovations in machine learning.

The takeout is that spam filtering is still very much a 21st century topic, and one that is continuing to evolve every day.