From Vienna, I moved on to Venice and since I stayed for some days, I could also take some time to have a closer look at how the 4G/5G networks perform in this city. Venice is obviously quite a special place and the first thing I noticed from a network point of view is that … Continue reading Venice Network Notes – Viva La Fibre!
Recently, I’ve spent a week on vacation in Vienna, and I used a bit of that time while walking around and spending time in cafés to have a look at the performance of the LTE and 5G networks in the city. With the EU’s ‘roam like at home’ rules, I didn’t need a local SIM … Continue reading Vienna Network Notes
I must have had one of the oldest cars in Cologne. In 2001, I bought a used Toyota Paseo from 1998 and have driven it until now. That’s 22 years, and for the past decade, people were already strangely looking at me whenever I showed up with my old and quirky car that had so … Continue reading Going Car-Less After 22 Years – A Journey Ends, a New One Begins
An idea that has been floating through the news in recent years is Edge Computing. One flavor of the concept is to have relatively lightweight client devices that receive pre-processed data from servers that are located close to the edge of the network instead of doing it themselves. Recently, I’ve come across two applications that … Continue reading Edge Computing – Virtual Worlds in UDP Packets
One nice thing about GSM ‘in the old days’ was, that there was a timing advance (TA) value that indicated to the mobile how much earlier it had to start transmitting relative to the network to account for the limited speed of radio waves. In my early ‘mobile days’, the TA was an invaluable help … Continue reading The LTE Timing Advance
I just had a look in my archive when I first started to see carrier aggregation in LTE networks. It turned out that, from my point of view, first networks and devices started to support the aggregation of 2 carriers with a maximum bandwidth of 2x 20 MHz in 2014. A few years later in … Continue reading LTE 5-Carrier Aggregation
In part 1 of this series, I’ve taken a look at the process of purchasing an eSIM online for roaming purposes and then downloading it to a smartphone. In this part, I’ll have a look at some technical details such as the home network operator of the eSIM, location of the Internet connectivity, performance and … Continue reading Downloading an eSIM – in Practice – Part 2
I’m running Ubuntu 20.04 on my notebook, which by now is around 2 years old. This means that some programs are of the same age, as newer versions are not included in the repository. For most programs, that is just fine for me. Some programs are evolving quickly, however, and when it comes to Wireshark, … Continue reading Compiling Wireshark on Ubuntu
A while ago, I had a closer look at HTTP/2 (from a 5G core network point of view), and how a client could detect during connection establishment if it can use this flavor of the protocol or not. The short answer to the question is that the client and the server use an extension parameter … Continue reading HTTP/3 and QUIC
After optimizing Firefox HTTP/1.1 settings for slow wireless connections 17 years ago (!) , I pretty much forgot all about it again, because networks became faster and default browser settings and features were adapted for the cellular world. Only recently did I have another look at HTTP, when I noticed that HTTP/2 is now widely … Continue reading Wireshark: Tracing Encrypted HTTP/2 Traffic