In a previous post I described how to use a Raspberry Pi as Wi-Fi access point and how to trace the data traffic of my smartphone in real time using tcpdump and netcat. The next logical step is of course to directly trace the network traffic on the smartphone. This has the big advantage that … Continue reading Cross-Compiling Tcpdump for Android
There are various way to use Wireshark to trace anything from local traffic to Wi-Fi packets and even Bluetooth. Recently, I’ve added yet another variant to my bag of tricks: Tracing on a Wi-Fi Access point with forwarding of all captured data to my PC for online debugging. When everything is put together I can … Continue reading Tcpdump, Netcat and Wireshark for Remote Logging
For those interested in getting a feeling of how Wifi works on the physical layer, Metageek’s Wi-Spy is the ideal tool. I’ve already reported about my first experiences here and here. Wifi has become very popular in Paris due to DSL being quite cheap. So it should thus probably not be surprising that I can … Continue reading Wifi Layer 1 Tracing with Wi-Spy – Part 3
After the more high level parts 1 and 2 on Starlink, it’s now time to have a closer look at how the Starlink downlink channel behaves. I’m totally amazed by the system and it performs very well in Germany. That being said, it probably comes as no surprise that on the IP layer, the graphs … Continue reading Starlink – Part 3 – Downlink Performance – The BBR Version
In the previous post on the topic, I gave a general overview of how Nextcloud and OnlyOffice can play together. There are many ways to combine the two online services and hence, installation instructions that can be found on the net from Nextcloud, from OnlyOffice, from third parties and from each with many different installation … Continue reading Nextcloud – OnlyOffice Install – Quick and Simple
Another crazy year, both good and bad in so many ways, is coming to an end, so here I go with time honored tradition of looking back to what moved me this year in tech! In The Wireless Domain Obviously, there’s been a lot going on in the wireless domain again. While some parts of … Continue reading Things That Moved Me in 2022
There must be few people on this planet that have not been affected by the Covid-19 pandemic this year. It has certainly brought profound changes in my way of working and in the things I did this year. So while the pandemic restricted me to stay at home most of the time, it ‘moved me … Continue reading Things That Moved Me In 2020
Quite a number of mobile network operators around the world these days support IPv4 / IPv6 dual stack operation. That’s nice but the real goal of the exercise is to eventually end up in an IPv6-only world without any IPv4 traffic in the network. Recently, I noticed that French mobile network operator Bouygues has also … Continue reading IPv6-only in a French Mobile Network
We are quite a bit into January 2018 already and I still haven’t come around to reflect which things from back in 2017 ‘moved’ me. But finally here we go this is my 2017 round up from cellular to history.
Most services on the Internet make use of a single TCP or UDP connection. The client opens a TCP connection from a random port to a well known port on the server (e.g. port 443 for HTTPS) and performs authentication and establishment of an encrypted session in that connection. Simple! In VoLTE, however, things are … Continue reading VoLTE – Some Thoughts On Port Usage