Eduroam as a Model for Future Public Wifi Deployments

Going significantly beyond the capacity and geographic reach of current cellular LTE coverage in cities requires to bring the cells to where the people are: Inside buildings. From a technical point of view small cells could do the job, they are now small enough to be installed just about anywhere. From a practical point of view, however, there are a number of major problems with that.

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‘Dealers of Lightning’ Revisited – Xerox Alto Videos

Picture of an AltoLast year I reviewed ‘Dealers of Lightning‘, a great book about Xerox PARC in the 1970 where pretty much all of the technology was invented we are still using today on our graphical user interface based PCs today. Over the past year a number of very interesting videos have appeared that are a great complement to the overall story and impressively show just how many things were invented there.

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Open Source LTE eNB and UE Implementation

A few years ago a number of clever guys figured out how to access the layer 1 functionality of a certain type of modem chip built into entry level GSM phones and implement the GSM stack on a PC. I had a lot of fun getting that to work in a virtual machine and I learnt a lot in the process. Now a few guys have come up with something at least equally impressive: An open source implementation of an LTE eNB base station and an LTE UE.

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VPN-Wifi-Pi Updated to Raspbian Stretch

Software updates are great because they keep installations secure and add new functionality. Moving from one Debian version to the next, however, is sometimes a bit painful for projects that modify system configuration files. My VPN-Wifi-Pi project that uses a Raspberry Pi as a Wifi Access Point and an OpenVPN tunnel to a VPN server for secure Wifi access in hotels and other places is unfortunately no exception.

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The 28 GHz 5G Frontier

5G is many things to different people. For most, 5G is about more network capacity and faster speeds for Internet access. The main challenge for this goal is that there is little spectrum still available below 6 GHz, a frequency that is generally seen as the limit for the current air interface technologies around. So 5G below 6 GHz brings only few benefits for the broadband Internet use case, it could easily be done with LTE as well. Ultimately, to get to higher speeds and more network capacity, higher frequency bands have to be tapped. The problem here is that with conventional technologies, communication range is severely limited.

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Eduroam Configuration App for Android

Setting up Eduroam on a PC securely including certificate checking during authentication to prevent password theft is quite a bit of a challenge but not impossible. On Android, things are even more difficult and it’s a bit strange that many universities are showing how to configure Eduroam manually on their help pages rather than linking to the Eduroam Configuration Assistant Tool (eduroamCAT) web page that makes things a lot easier.

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Small Cell Network Sharing As A Way Forward To Network Densification?

Recently, I’ve been thinking a bit how network densification will look like once the capacity of macro cells is no longer sufficient to satisfy demand. As statistics keep telling us, a significant part of cellular data traffic is not generated outdoors but actually indoors. When densifying the network its unlikely that this would work well from the outside, densification has to be done from within buildings.

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The Mouse – An Endangered Species?

While traveling, I recently spent some time on a University campus in the US and sat in the Library reading room for a few hours. When I observed the students there for a while I noticed that none, not even a single one of them used a mouse with their computers. Instead, they were all using the touchpad of their notebooks while I was the only one in the reading room who actually had a mouse at the side of this computer.

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