Verizon: The End Of Circuit Switching – The End Of An Era

Most cellular network operators around the world still have a circuit switched core network today for voice and SMS services for their 2G/3G access networks. There are a few exceptions like one operator in India that launched with an LTE-only VoLTE network a few years ago. But apart from a few, that is the status quo. And it’s unlikely to change for most operators for the following reasons:

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BBB – How to Add an Imprint and Privacy Statement

Out of the box, BigBlueButton and Greenlight do not have an easy way to link to an imprint or privacy statement. As I am operating a server for others, that’s a bit of a problem as I really want to inform people how the server and the service deals with private data. So when I had a bit of time, I had a closer look how an imprint and privacy statement link could be added to the footer (Powered by Greenlight…) on every page. In the end it boils down to modifying the Greenlight source which requires a bit of effort the first time around. However, once you know where to look and what to do, it can be done in a few minutes. So here’s my procedure:

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Conversations: The Technology Behind Voice and Video Calls

After having had a look at the data rate of Conversations voice and video calls, the next thing I wanted to know was which underlying technology is used for the audio and video streams. Building such a thing from scratch, including authentication, encryption and overcoming NAT firewalls is a monumental task. So how was it done?

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4G/5G Dynamic Spectrum Sharing – Technical Details

Back in November 2019 I had a post on how to get to nationwide 5G coverage. One of the options to do that is Dynamic Spectrum Sharing (DSS), a method to run LTE and 5G NR in the same channel. For a general introduction, see my post from back then. In the meantime a number of interesting resources have been published that give quite a lot of background information on the technology that I thought I should link from here.

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BigBlueButton – The Terabyte Week

Image: data traffic over 3 daysAn interesting piece of data when operating a video conferencing server is how much data is transferred over the course of a week or a month. When I initially calculated the potential amount of data my BigBlueButton server could potentially consume over the course of a month with 70 people in 4 sessions all showing their videos, 10 hours a day, 5 days a week, I came up with around 25 TB per month. That would have been all right since my virtual server rental contains 20 TB of traffic a month, and each additional TB is billed at a euro or two. But that was the theory, how about practice?

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Wi-Fi 6 – 802.11ax – Some Tech Resources

In 2019 and 2020, I’ve seen first Wi-Fi 6 (802.11ax) capable devices coming to the market, mostly smartphones. On notebooks, the standard still hasn’t made a real impact, even the current Lenovo Thinkpad X390 still comes with a Wi-Fi 5 (802.11ac) modem. Also, on the Access Point side, first products have become available but the impact so far is still small. Nevertheless, now is the time to have a look at the spec and here are a number of resources that give a good technical overview of what’s new:

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Base Station Changes Over The Years

Image: Cell site update 2020I have a cell site sitting on the building right across the street and two years ago I had a post here with some pictures of how the site has changed over the past 10 years. On average, changes are done every two years. So I guess it was time again when things were once again changed recently.

If you compare the picture above with those in my post 2 years ago, you will notice the additional small antennas that have been installed next to the bigger ones. Those are typical 5G n78 (3.5 GHz) active antenna systems (AAS)! In other words, the cell site has been upgraded to 5G!

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