Salamander

If the timing is right, I would bring a mushroom grow bag with mushrooms sprouting.

If not… probably my radiacode gamma spectrometer and some of my radioactive items. Maybe a clock with radium painted dials and a piece of trinitite. I think that there are many different points of discussion that can be of interest to a broad audience (radioactivity, spectroscopy, electronics, US labor law story of the radium girls, nuclear explosions, background radiation… etc). As a bonus I can bring a UV flash light and show the radium fluorescence. Adults love UV flash lights.

I am also quite interested in this. It is not something that keeps me awake at night, and I am not particularly paranoid about it. But I find that working towards answering this question is a fun frame from which to learn about electronics, radio communications, and networking.

Since this appears to be something that is causing you some anxiety, I think it is better if I start by giving you some reassurance in that I have not yet managed to prove that any electronic device is spying on me via a hidden chip. I don’t think it is worth being paranoid about this.

I can explain some things that could be done to test whether a Linux computer spying. I am not suggesting that you try any of this. I am explaining this to you so that you can get some reassurance in the fact that, if devices were spying on us in this manner, it is likely that someone would have noticed by now.

The “spy” chip needs some way to communicate. One way a chip might communicate is via radio waves. So, the first step would be to remove the WiFi and Bluetooth dongles and any other pieces of hardware that may emit radio waves during normal operation. There is a tool called a “Spectrum Analyzer” that can be used to capture the presence of specific radio frequencies. These devices are now relatively affordable, like the tinySA, which can measure the presence of radio frequencies of up to 6 GHz.

One can make a Faraday cage, for example, by wrapping the PC with a copper-nickel coated polyester fabric to isolate the PC from the radio waves that are coming from the environment. The spectrum analyzer antennas can be placed right next to the PC and the device is left to measure continuously over several days. A script can monitor the output and keep a record of any RF signals.

Since phones are small, it is even easier to wrap them in the copper-nickel polyester fabric alongside with the spectrum analyzer antenna to check whether they emit any RF when they are off or in airplane mode with the WiFi and Bluetooth turned off.

What this experiment may allow you to conclude is that the spy chip is not communicating frequently with the external world via radio frequencies, at least not with frequencies <= 6 GHz.

Using frequencies higher 6 GHz for a low-power chip is not going be an effective method of transmitting a signal very far away. The chip could remain hidden and only emit the signal under certain rare conditions, or in response to a trigger. We can’t rule that out with this experiment, but it is unlikely.

A next step would be to test a wired connection. It could be that the spy chip can transmit the data over the internet. One can place a VPN Gateway in between their PC and the router, and use that gateway to route all the traffic to their own server using WireGuard. All network packets that leave through the PC’s ethernet connection can be captured and examined this way using Wireshark or tcpdump.

If one can show that the device is not secretly communicating via RF nor via the internet, I think it is unlikely that the device is spying on them.

This is what I think, but if anyone understands it differently please correct me.

Vertical scalability refers to scaling within a single instance. More users join and they post more content, increasing the amount of disk space needed to hold that memory, network bandwidth to handle many users downloading comments and images at once, and processing power.

Horizontal scaling refers to the lemmyverse growing because of the addition of new instances. The problem in this form of scaling is due to the resources that an instance has to use due to its interactions with other instances. So, you may create a small instance without a lot of users, but the instance might still need a lot of resources if it attempts to retrieve a lot of information (posts, comments, user information, etc) from the other larger instances. For example, at some point a community in lemmy.ml might be so popular that subscribing to that community from a small instance would be too much of a burden on the smaller instance because of the amount of memory required to save the constant stream of new posts. The horizontal scaling is a problem when the lemmyverse becomes so large that a machine with only a small amount of resources is no longer able to be part of the lemmyverse because its memory gets filled up in a few hours or days.

I think this underestimates how users will naturally gravitate towards more centralized instances, or they’ll give up because the bigger instances are closed.

(This is purely my personal opinion, of course!) In the scenario in which a few large instances dominate, the idea of the fediverse failed. One may estimate the likelyhood of success or failure given how they expect humans to behave, but in the end experiment beats theory. I think that for the fediverse to work a significant cultural shift has to occur, but I don’t think that it is an impossible shift. I would like the fediverse to succeed, and so I choose to take part in the experiment.

This also ignores that the system isn’t horizontally scalable at all, so scaling up gets even more expensive

Yes, that might cause some serious issues. The project is still in an early-development phase, and I don’t understand the technical aspects well enough yet to be able to identify whether there is obviously a fundamentally invincible barrier when it comes to scalability. My optimistic hope is that the developers are able to optimize horizontal scalability fast enough to meet the demand for scale. If it turns out to be impossible to scale, then only rich enough parties would be able to have viable instances, and that could be a reason for failure.

A small cloud server + a domain name costs less than a Netflix subscription. The developers have taken care to package lemmy in ways that are relatively straight forward to deploy, so a dedicated person with a small amount of experience can have an instance up and running in an evening. As long as a few percentage of users are willing to pay a netflix subscription to keep a server running, the financial burden would be spread.