Apple AirTag
Image: Apple

Have you spent any time at the airport during the Holidays? You may have had to deal with long queues, lost luggage and… Apple AirTags. What is an AirTag and most importantly: how does it use Internet connectivity to help you find your missing stuff? Whether is’s your suitcase that’s lost at the airport because of a lack of baggage handlers, your laptop that you may have left at the office or simply your purse that could be lying underneath a pile of clothes somewhere in your home – let’s find out how an AirTag can help you recover it!

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A word about HTTP status codes: they’re the numbers webservers send back to your browser in response to your requests for webpages and they’re used to let you know if everything went well. Surely you’re familiar with 404 (not found) in case you’re looking for a page that just doesn’t exist, or you may have seen 500 (server error) to indicate not all is well with the webserver. You might also know the one you don’t usually see: 200 (ok) means everything went without a hitch. In fact, there’s lots more status codes that can be used to alert you about all kinds of conditions.

So, while status codes are a small but important part that makes the World Wide Web run, cats are surely another important part! Who needs a boring list to learn more about status codes, when instead we can combine the two. Please click this link to proceed to

Image: IOTA Foundation

Cryptocurrencies are hot. In our last post we talked about Bitcoin: it has the potential to change our world in many useful ways, but at a price. To keep its blockchain secure, Bitcoin requires as much energy to run as entire countries. In a world where climate change is a growing concern, people may start to ask questions.

In fact, there are a number of alternative technologies in development. An interesting example is IOTA, which is envisioned as a distributed ledger for the Internet of Things. It’s not based on a blockchain, but instead uses a Directed Acyclic Graph called the Tangle. So, what exacly is the Tangle, how will it allow payments between smart devices, and how is it different from a blockchain?

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Image: Bitboy – Bitcoin forums, public domain

As a reader of this blog, you’re probably familiar with Bitcoin. You may have even invested in some, in hopes of becoming the next Bitcoin billionaire. In fact Bitcoin and the underlying Blockchain technology are probably the most exciting new application of networked technology that we’ve seen in quite a while. We’ve talked before about how Blockchain is not just a new way to make payments, but can be used to record all kinds of transactions. It could potentially improve many parts of life, from preventing slave labour to having sex…

These good things, however, come at a price. The security of Bitcoin depends on so-called miners. These miners are a decentralised network of computer systems that create new Bitcoin while verifying previous transactions. Their work consists of performing some quite intensive calculations and to be rewarded for that (they can receive an amount of Bitcoin), they need to be the first among the miners to finish these calculations, and also correctly find a random number.

It’s a bit like trying to win the lottery: just like you could improve your chances of hitting the jackpot by buying more tickets, in this case you increase your chances of being rewarded with precious Bitcoin by purchasing more and more processing power. This has led to people creating ‘mining farms’, consisting of large numbers of machines with specialised hardware, trying to crunch numbers faster and faster.

As you can imagine, these mining farms consume huge amounts of power. How much exactly is hard to say, but studies by the Cambridge centre for alternative finance estimate it may take as much as 130 terawatt hours a year to keep Bitcoin running, which is comparable to the yearly electricity consumption of a country like Argentina or the Netherlands! To make matters worse, many large mining farms are placed in countries where energy is cheapest, and those are not necessary places that invest much in green energy or have strong environmental regulations.

At a time when global warming and climate change are major concerns, this vast energy consumption may turn out to be Bitcoin’s undoing. Time will tell if Bitcoin can overcome these environmental concerns, or if attention will slowly shift to alternative technologies.

Update: meanwhile, people are finding other ways to make cryptocurrency more eco-friendly, using the heat generated by their mining rigs to warm their homes and strawberry farms!

British Cab
Image: Deeana Arts on Pexels

As a consequence of Brexit that I personally hadn’t seen coming, a large number of UK citizens stand to lose access to their website and email addresses. Now that the UK has officially left the European Union, over 81.000 domain names ending in .eu will be inactived. As their owners no longer meet the requirement of being a EU citizen, they will not be entitled to own a domain under the .eu top level domain.

For those affected that still aspire to having a bit of exotic and international allure in their domain names, may I suggest registering a .Amsterdam domain instead?

Update: ironically, one of the websites affected is for Leave.EU. The organistion that has spent years campaining for the UK to leave the EU, now has had to leave Britain and register in Ireland instead, to keep access to its website.

The social dilemma

Sometimes, on this blog, we offer some recommended reading. Today, I’d like to suggest some recommended watching, at least for those that have a Netflix subscription or know someone who does. The documentary ‘The Social Dilemma‘ is a fascinating story, related by Silicon Valley insiders, about how social media have slowly turned into gruesomely effective tools to capture your attention and sell it to the highest bidder.

To paraphrase from the movie: on one side of the screen is you, and on the other side of the screen are dozens of the world’s best experts, aided by supercomputer AI’s. They do not have your best interest in mind. Imagine how that battle is going to play out?

While I’m certainly very worried by such developments, I still strongly believe computer networks can be a force for good, bringing people together and sharing knowledge ever more widely. In the end, it’s in our own hands to decide how we’ll design the tools of the future and at what price we’re willing to use them. Initiatives like the Decentralised Web offer a different vision for the future, where we could take control of our data back from big business.

Image: Apple / Google

With much of the world still suffering the effects of the Coronavirus, many of us are hoping for a vaccin or cure to be found. With many suggestions being looked at, from swallowing cleaning agent (sorry Donald: not helpful!) to utilising Llamas (not as crazy as you may think!), a breakthrough may happen, but experts caution us it may take years for an effective vaccin to become available.

Meanwhile, contact tracing apps promise us a different road out of lockdown. What is contact tracing, what technology would an app use to do this, and what are some of the privacy concerns involved? Read more in this article, where we look at a number of different ways to make this happen.

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Mouth mask
Image: Anna Shvets on Pexels

When talking about networks, the spread of viruses has always been a concern. Still, with the spread of the real-life Coronavirus bringing turmoil all over the world, it’s easy to realise some things are more important than computer networks: our health and the health professionals working tirelessly to keep us safe.

In the meantime, let’s have a look at some of the different ways the Covid-19 virus is not just influencing the daily lives of millions of people, but our networks as well.

  • Many of us are now working from home, increasing the demand for applications that support online collaboration, video conferencing and distance learning. Many companies are now providing free access to such services. Also, demand for webcams is reaching new heights.
  • While we’re sitting behind our computer, working from home, one of the best things we could be doing is to participate in Folding at home: using our computer’s processing power to simulate the dynamics of COVID-19 proteins and help in the hunt for new therapeutic opportunities.
  • Netflix and Youtube will reduce the quality of their video streams at the request of the European Union. With many of us confined to our homes, streaming services are seeing increased use and this measure will help ensure enough Internet bandwidth will stay available to conduct our other business online.
  • The registry of domainnames within the .org top level domain was going to be sold to a private equity company. This sale might be delayed, as many charities, NGO’s and right groups are depending on these .org domains for their online presence.
  • Finally, for all of us still trying to ‘catch ’em all’, Pokemon Go has made it easier to capture those rare ones, without having to leave your home.