If you’ve been sifting through the world of VPNs trying to find the right service, you may well have come across the term AES 128 encryption. It’s not hard to guess from the name that this is something related to the way data is encrypted as it passes over the web, but is there more to how AES works that security-conscious web users need to know?

This article will look at the ins and outs of AES 128, discuss how it fits into the world of encryption and, in particular we’ll look at the question of AES 128 vs 256. At the end, you should be in a great position to pick the kind of encryption you use as you surf the web.

What is AES? A Quick Introduction

AES stands for “Advanced Encryption Standard”. The term first cam into use when it was introduced by the American National Institute for Standards in Technology (NIST) back in 2001, and it’s been commonly used in online security circles ever since.

While AES was coined in America, the roots of the actual encryption standard reach back to Belgium in the 1990s, when it was invented by crypto-specialists Vincent Rijmen and Joan Daemen. The pair submitted a proposal to NIST when they were seeking a common encryption standard, and won the contract. The rest was history.

Because of its high level of security, the US government integrated AES 128 into all of its most sensitive data operations. And when the government led, most online businesses and other organizations followed. By 2005, the whole web relied on AES as a gold standard for encryption, and a standard that applied almost across the world.

AES is also extremely fast – another factor which recommended it to NIST. This allows it to be used effectively over security features like firewalls, as well as firmware where efficiency and low throughput are vital. The mixture of security and efficiency has really been the “magic recipe” behind AES’ success.

How AES Works

In AES 128, data is separated into blocks of 128 bits, hence the suffix in the name. It then applies cryptographic keys to this data, scrambling it so that it is incomprehensible to those without the keys. These keys could be 128 bits themselves, but are often 192 or 256 bits.

To get a feel for how it works, check out this AES encryption example. As you can see from the AES encryption example, things become extremely complex very quickly, turning a simple text message into a secure, encrypted code.

The standard takes the form of an “symmetric key algorithm”, which means that anyone who wants to read data encrypted using AES 128 must have the keys in their possession. This generally means that those using the standard require secure ways of distributing keys across their network – a logistical challenge for services like VPNs.

When data is compressed, it undergoes a series of “rounds” of encryption. In the case of AES 128, there are 10 rounds, which essentially take chunks of data and mix it up according to the recipe specified by the AES key. It’s at this stage that the key is generated – allowing recipients to untangle the web of encryption. Without it, anything sent via AES would be totally impossible to understand.

Comparing AES 128 vs 256

While choosing VPNs or generally researching online security, you’ll probably have come across AES 256 as well. Unsurprisingly, AES 256 is also a symmetric encryption system, and it’s the natural successor to the 128 bit version.

Because it uses 256-bit keys on the 128 bit base, it theoretically delivers more secure encryption than AES 128. In AES 256, there are also 12 rounds of encryption, compared with 10 for the 128-bit version.

Why was the standard changed from a 128 to 256-bit setup? Basically, it all comes down to security. Tests have found that attackers can have AES 128 cracked in “1.02 x 1018 years” compared with “3.31 x 1056 years” for AES 256. That’s obviously a very long time in both cases, but it’s not the point. With rapidly developing hacking technologies, the difference between 128 and 256 bit encryption is massive.

As a result of this, 256-bit AES encryption has rapidly displaced its ancestor, as experts have found AES 128cracked more and more easily. So bear that in mind if you’re choosing between a VPN with 256 or 128-bit encryption.

Is AES 128 Secure 2018

So, if AES 256 is superior, is it still OK to use AES 128 if no alternatives are available?

At the moment, when assessing is AES 128 secure 2018 web users can breathe easily. While we’ve noted that the theoretical security differences between 128 and 256 bit encryption are huge, on a practical level, 128-bit encryption remains very safe – and much, much safer than older 56-bit DES versions. For a more in-depth appraisal of the merits of AES, check out our What is AES explainer.

Over the years, security experts and hackers have worked hard to understand whether AES 128 is secure, so we know quite a lot about its vulnerabilities. For example, in 2011 researchers discovered that “biclique attacks” could overpower AES encryption – raising some concerns. But this only applied at levels of complexity which render it obsolete in the real world.

While there’s a risk that quantum computing and other technologies could give hackers an advantage when brute-forcing AES-based encryption, we’re nowhere near that stage in 2018.

Should we rely on AES 128 or 256 for online security?

While AES 128 is largely being superseded by AES 256, it’s still going to be used for millions of encrypted transmissions today. And it’s not going anywhere for a while. As we’ve seen, it remains relatively secure, and its speed advantages still make it preferable to 256 bit encryption for many purposes.

The bottom line is that AES 128 delivers strong protection against surveillance and cyber-crime. It’s not perfect – nothing is – but it remains a potent privacy tool.