At the VCFB This Wekkend!


While I’m typing this I’m sitting in the train from Cologne to Berlin, on my way to this year’s Vintage Computer Festival Berlin (VCFB). It’s beautiful sunny weather, unlike last year, when an autumn storm turned my train trip into a nightmare.

Like last year, I have brought a little exhibit with me again, this time about GEOS, a graphical user interface for the masses that was very popular in the second half of the 1980s. In addition, I’ve spent the last few weeks collecting my thoughts and pictures about the evolution of wireless networks and mobile data communication in the past decades. I will present the result in a 90 minute talk tomorrow, Saturday, 12 October. The talk will be recorded and perhaps also live streamed in case you are interested. I intend to hold the talk in German but there will surely opportunities in the future to record an English version as well.

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Android Opens Links With GPS Coordinates in Osmand

Open with OsmandSometimes it is just a lot more convenient to do a map search on the PC rather than on the phone. Nevertheless I still want to have the result in Osmand (OpenStreetMap for Android) on my smartphone for later use, e.g. for car navigation. So my approach so far was to first search the location on the PC and once I knew where it is I would manually locate and bookmark it on the smartphone again. Far from ideal… However, I just found out a much simpler way to do this by accident:

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Backbone Bottlenecks

backbone congestionAfter upgrading to VDSL vectoring with a 100 Mbit/s downlink and 40 Mbit/s uplink in Cologne recently, I soon figured out what to do with the additional uplink speed: Advanced synchronization with my network behind a fiber line in Paris. Equally soon I noticed that no longer is my access link the bottleneck but rather under-dimensioned backbone links. So I had to find a way to creatively route my traffic around the problem.

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5G TDD: Synchronization Across Networks Required?

I recently came across this paper of Huawei on 5G Spectrum matters and one paragraph in particular caught my attention:

“[…] inter-operator synchronisation and alignment of uplink/downlink transmissions (slot and frame synchronization) is […] necessary for efficient deployment of 5G NR networks in unpaired assignments.”

In other words this sentence says that network operators using adjacent spectrum have to synchronize their radio networks to avoid interference. So why is this necessary and what exactly does that mean?

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Roaming In Monaco

Monaco harborRemember the days when you traveled in Europe and had to pay high prices for voice and data roaming as soon as you crossed a border or had to buy a local SIM card for reasonably priced mobile Internet access? It seems like those days are long gone but that’s actually not the case, free roaming in the EU only came into effect last year. And even worse, there are still places on mainland Europe apart from Switzerland that are not part of the EU, where one gets a bitter reminder of how things were in the past. An interesting example is Monaco.

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The Future of Microprocessors

Interested in the past, present and the future of microprocessors? If so, the video of Sophie Wilson talking about the ‘Future of Microprocessors’ at Juliacon is a must see! In case the name Sophie Wilson doesn’t ring any bells, have a look at what Wikipedia says about her.

Her presentation will not only tell you about the history of microprocessors but also why performance hasn’t really increased in the past years, the reasons behind this and why the price per transistor on a chip has started increasing again with further miniaturization instead of a further decreasing, which has fueled Moore’s law for the past decades. And most important she will give here educated opinion on where we will go from here.

5G EN-DC: What is Single Uplink?

The abbreviation EN-DC (eUTRAN New Radio – Dual Connectivity) indicates that in this type of 5G deployment, 4G LTE and 5G NR will be used simultaneously. However, it looks like that the combination of some frequency bands might prove to be a bit problematic due to self interference as laid out in this interesting whitepaper recently published by Keysight (see page 4).

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VDSL and G.Fast Coexistence

A few days ago, there’s been a great talk about G.Fast at the Local Chaos Computer Club chapter (C4, Cologne) by Stefan Förster of NetCologne. Here’s a link to the video of the talk (in German). I was particularly interested, because NetCologne recently announced that they have finished their trial (using the existing telephony copper wiring in buildings) and are about to start commercial service. This sounds like great news and I had quite a number of questions in my mind, including how can coexist with VDSL Vectoring that the the national incumbent offers in Cologne today.

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